目录 CONTENT
一、 前言 FORWARD
二、 电伴热产品 Introduction
1. RDP2-J3单相恒功率电热带 Single phase constant watt heating cable2. RDP3-J3三相恒功率电热带 Three phase constant watt heating cable3. RDP2-J4 高温恒功率电热带 Hi-temp constant watt heating cable4. CRH 船用电热带 Marine constant heating cable5. RDL-J6 变功率电热带 Power limiting heating cable6. LT、HT自限式电热带 Self-regulating heating cable7. RDC 串联电热带 Series resistance heating cable8. 集肤电伴热系统 Skin effect heating system9. LDB 挠性电热板 Flexipanel
10. 短路加热法 Impedance heating system11. 融雪电缆 Snow and ice melting12. MI 电缆 Mineral cable
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三、 电伴热产品附件 Accessories
1. 通用隔爆型接线盒 General Ex-proof power connection box2. 通用增安型接线盒 General Increased-Safety Power connection box3. 防爆温度控制器 Ex-proof temp-controller
4. 增安型电源接线盒 Increased-safety power connection box5. 增安型中间接线盒 Increased-safety splice connection kit6. 防爆终端接线盒 Ex-proof end termination kit7. 铝胶带 Aluminum tape
8. 耐热压敏胶粘带 Hi-temp fiberglass tape9. 喉卡 Pipe clamp
10. 示警铭牌 Alarm nameplate11. 船用附件 Marine accessories12. 配电箱 Power panal
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四、 安装 Installation
1. 安装总则 General installation guide2. 电热带的安装 Installation of heating cable3. 故障检修 Troubleshoot
4. 挠性电热板的安装 Flexipanel installation
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五、 产品选型设计及计算方法 Design and selection
1. 管道及附件散热量的计算 Heat loss of pipe & accessories2. 罐体容器散热量的计算 Heat loss of vessel3. 有关公式介绍 Formula
4. 选型方法 Slelection of heating cable
5. 特殊情况的设计与计算 Design and calculation in special condition47515353545657
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附录一、 对电热带常见问题的回答 Frequent queries and answer附录二、电伴热咨询表 Information sheet
前言 FORWARD
(一) 电伴热概念
电伴热是用电热来补充被伴热物体在工艺过程中所散失的热量,以维持介质温度在某一范围内。通俗而言,介质温度会随着输送长度的增加而下降(由于对环境的散热),电伴热就是为了防止或阻止此类情况的发生,使介质温度维持在某一范围内。
(二) 电伴热产品概况
各种电伴热产品均有其特点,也同时存在不足,至今还没有靠单一的电伴热产品来满足所有工艺温度伴热的要求。为此我公司通过了二十多年的发展,开发了多品种、多规格的电伴热系列产品。主要有单相恒功率电热带、三相恒功率电热带、自控温电热带、串联式电热带、变功率电热带、集肤电伴热系统、融雪电缆及挠性电热板等等。
(三) 电伴热产品应用领域及其特点
1. RDP2(3)-J3 型单相(三相)恒功率电热带
RDP2(3)-J3 恒功率电热带主要应用于各种管线和仪表的防冻、保温。特点是维持温度高,最高可达150℃。可用于工厂一区、二区防爆场合。三相带主要用于较长管道的伴热。
2. LT、HT自限式电热带
LT、HT自限式电热带其基带从美国引进,它们主要特点是其输出功率能随管道温度的变化而变化,主要应用在各种管道阀、仪表的保温、也可用于防爆场合。
3. RDC串联型电热带
RDC串联型电热带主要发热体是电缆芯线,特点是可用于长输管线伴热,目前单点电源供电最大长度可达3.6Km。
4. RDL变功率电热带
RDL变功率电热带与恒功率电热带基本相似,但有一定的自控温特性,最高维持温度可达150℃.
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前言 FORWARD
5. 集肤效应电伴热系统
6. 融雪电缆
7. 短路加热系统
8. LDB挠性电热板
9. MI电缆
集肤效应电伴热系统是基于电流集肤效应的原理;其主要优点是维持温度高(最高可达230℃)、功率密度大、伴热距离长,一个电源点的伴热距离最长可达24Km。
融雪电缆主要用于公路、桥梁、机场跑道的融雪防冻,配备先进的测雪感应器,能自动控制融雪电缆;一般以功率150W/m2,200W/m2和300W/m2,进行设计。
短路加热法是整个电伴热系统中又一种电伴热方式。它不是采用电热带伴热,而是靠自身的管道产生的热来维持管中的介质温度。主要特点是维持温度高,可靠性好。
LDB挠性电热板是用于油罐、槽池和容器的电伴热产品;可用于工厂一区、二区爆炸性气体T3 组场合;特点是伴热比较均匀。
MI电缆用在需要高温电伴热的场所,最高伴热温度可达590℃,也可用在某些加热场合,具有很高的机械强度。可用在防爆场合。
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前言 FORWARD
(四) 电伴热规格选择
电热带规格串联型电热带铜发热芯MI矿物电缆Inconel 外壳0.5 to 12恒功率电热带(单相恒功率电热带)氟塑料0.5 to 12玻璃纤维0.5 to 12恒功率电热带(三相恒功率电热带)氟塑料0.5 to 14玻璃纤维0.5 to 14自控温电热带低温型高分子0.5 to 4发热芯高温型高分子0.5 to 8发热芯短路加热法0.5 to 6集肤效应电加热系统聚烯烃塑料2 to 48氟塑料2 to 483 to 1002 to 2102 to 2102 to 3302 to 330160180AAAAAAAAAAAAAAAAA(10W/m可达150℃)外壳或发热芯材料管道尺寸(in)管道长度(米)10℃65℃A 管道维持温度120℃200℃AA260℃500℃980℃0.5 to 6150 to 3600AAAAAAAA3 to 100150 to …150 to …BAABAAAAAAAAAA: 合适 B: 合适但不经济
注: 管道尺寸,是针对单根电伴热使用而言,大的管道需要更多的电伴热电缆,并不是说,大管道尺寸,该电缆不能使用。
最高允许维持温度与电热带的米功率有着密切的关系;就单相恒功率电热带而言,其最高维持温度与米功率之间的关系曲线如下:
米功率(W/m)最高维持温度℃
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电伴热产品 Introduction
一、 RDP2-J3 型单相恒功率电热带 Single phase constant watt heating cable
加强护套 over jacket
编织 metal braid外护套 outer jacket发热丝 resistance wire
母线 bus
母线绝缘 bus insulation主绝缘 inner insulation
单相恒功率电热带主要用于各种管道、仪表的防冻、保温、最高维持温度150℃,可用于工厂一区、二区爆炸性气体场合。Single phase constant wattage is applied in frost and maintenance temp of pipeline and instrument. Max maintainingtemperature about 150℃. It may be used in hazloc areas.
1、 型号含义 Type number nomenclatureRDP 2 (Q) - J3 -额定功率: W/m watt per meter
绝缘层代号: J3-F46 氟塑料 Insulation:J3-F46 fluorpolymer
Q:加强型、普通型不注 Strengthen range (ordinary range no mark)
2:芯线数2,单相220V工作电压 No of bus wires, single phase operating voltage: 220VRDP:并联型电热带 heating cable
例:RDP2-J3-20 : 表示绝缘材料为F46氟塑料,20W/m的单相普通型恒功率电热带
RDP2(Q)-J3-30 : 表示绝缘材料为F46氟塑料,30W/m的单相加强型恒功率电热带
Example: RDP2-J3-20: insulation material:F46,20W/m single phase constant heating cable
2、 产品结构与工作原理 Construction and principle
电源母线为二根平行绝缘铜线,在内绝缘层上缠绕电热丝,并将电热丝每隔一定距离(即“发热节长”)与母线连接,形成连续并联电阻。母线通电后,各并联电阻发热,因而形成一条连续的加热带。
Twin bus wires with extruded high-temp flouropolymer primary insulation, A resistance wire heating element is spirallywrapped around primary insulation contacting alternate bus wires at specific intervals forming heating zone, The twin buswires supply voltage along the entire length of heating cable.
3、 产品规格及主要技术特性 Performance and rating data
表2-1
*流体最高维持温度: 是指管道内介质需要维持的最高工艺温度,一般不宜超过本表规定值。
*maximum maintenance temperature: maximum maintenance fluid flow temp in pipe not allow to exceed it
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电伴热产品 Introduction
额定电压 Rated Voltage: 220V
常态绝缘电阻 normal insulation resistance: ≥20MΩ介电强度 dielectric test: -2000V 50Hz/1min绝缘层材料 insulation material: F46 氟塑料最高耐温 maximum withstand temperature: 205℃防爆标志 explosion-proof marks: e ⅡT3防护等级 type of protection: IP54
防爆合格证证号 explosion-proof certiticate of inspection: GYB94389尺寸(包括编织和外护套) Size (including braid & oversheath): 6.3×9.5mm
4、 产品特点及应用场合 Production feature and applications
恒功率电热带单位长度的发热量恒定,使用的电热带越长,输出的总功率越大。该电热带在现场能按实际需要长度任意剪切。此外具有柔软性,可以方便地紧贴管道表面敷设。电热带外层的编织层不仅起着传热和散热作用,提高电热带的整体强度,同时还能作为安全接地线。
The constant watt heating cable provides a constant power output each zone, The longer heating cable use, Thegreater total power output, It is flexible and can be cut at any point to fit pipepline and installation easy, The overbraidprovides a conductive ground path and increase strength and heat transfer.
本电热带适用于管道、阀门、泵体的伴热、防冻和保温,或者维持仪表管线的工艺温度,如:a. 用于在正常情况下连续流动的低凝固管线使用,可避免介质因停止流动而凝固。b. 需要严格控制作业温度的液体管线的伴热和保温(须配用温度控制器)c. 寒冷地区自来水管道及阀门的防冻、排水管、抽水管和冷凝管路的防冻。d. 沿海井台管道的伴热防冻。e. 一般管线和仪表管线的伴热保温。
f. 井口采油树伴热(取代水套炉),污水井伴热。g. 混凝土预制件防冻养护。
RDP2 single phase constant heating cable is ideal for use maintaining fluid in pipe, valve and pump or maintain pipelinetemperature. Such as:
a. Low solidity point fluid pipelineb. Liquid pipeline requires temp-controlc. Water pipe and valve in cold areasd. Coastal platform pipee. Pipeline instrumentationf. Oil exploit tree of wellhead
g. Concrete prefabricated components
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电伴热产品 Introduction
二、 RDP3-J3 型三相恒功率电热带 Three phase constant watt heating cable
加强护套 over jacket
编织 metal braid外护套 outer jacket发热丝 resistance wire
母线 bus
母线绝缘 bus insulation主绝缘 inner insulation
三相恒功率电热带和单相恒功率电热带的原理基本相同,不同之处是单相带采用单相供电,三相带采用三相三角形供电,三相带除有单相电热带的特点外,特别适用于长距离、大口径管道的伴热和保温,可用于工厂一区、二区的爆炸性气体混合物T3组场合。
The feature of three phase cable is similar to that of single phase cable. The difference is that the power is supplied bytriangle construction, It is suitable for long pipe, big diameter pipe heat tracing. It is suit for using in ordinary and hazlocareas.
1、型号含义 Type number nomenclature
RDP 3 (Q) - J3 -额定功率: W/m watt per meter
绝缘层代号: J3-F46 氟塑料 Insulation:J3-F46 fluorpolymer
Q:加强型、普通型不注 Strengthen range (ordinary rang no mark)3:芯线数3,380V工作电压 number of wires 3; voltage 380VRDP:并联型电热带 heating cable
例:RDP3-J3-40 : 表示绝缘材料为F46氟塑料,功率为40W/m的三相加强型恒功率电热带 Example: RDP3-J3-40: insulation material:F46,40W/m three phase constant heating cable
2、 产品结构与工作原理 Construction and principle
三根平行的绝缘铜绞线为电源母线,在内护套绝缘层外缠绕电热丝,并将该电热丝每隔一定距离(即“发热节长”)分别依次与电源母线AB-BC-CA-AB……反复循环连接,在每二相间形成连续并联电阻。当母线通以三相电后,各并联电阻同时发热,因而形成一条连续三相供电的加热带。
The tree parallel bus wries supply voltage a long the entire length of the heating cable. A resistance wire heatingelement is spirally wraped around inner insulation contacting alternate bus wire (ab-bc-ca-cb……) at specific intervalsforming heating zone.
3、 产品规格及主要技术特性 Performance and rating data
表2-2
*流体最高维持温度: 是指管道内介质需要维持的最高工艺温度,一般不宜超过本表规定值。
*maximum maintenance temperature: maximum maintenance fluid flow temp in pipe not allow to exceed it
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电伴热产品 Introduction
额定电压 Rated Voltage:380V
常态绝缘电阻 normal insulation resistance: ≥20MΩ介电强度 dielectric test: -2000V 50Hz/1min绝缘层材料 insulation material: F46 氟塑料最高耐温 maximum withstand temperature: 205℃防爆标志 explosion-proof marks: e ⅡT3防护等级 type of protection: IP54
防爆合格证证号 explosion-proof certificate of inspection: GYB94390尺寸(包括编织和外护套) Size (including braid & oversheath): 12×6.3mm
4、 产品特点 Production feature
RDP3-J3 型三相电热带除具有和RDP2 型单相电热带相同的特点以外,还有以下优点:a. 三相电热带的最大允许使用长度高于单相电热带。b. 在大规模应用电热带的场合,能均衡电网负载。
c. 三相带由于采用三根芯线,使电热带更趋扁平,降低了表面发热负荷,增加对管道的热传导面积,提高了电热带的热传输效率及最高维持温度。
It has more advantage RDP3 over RDP2 . such as:
a. The longer single phase cable use, The greater voltage drop in the end. The three phase cable provide more longerthan single phase cable by one power feed point, It decrease cost in project.b. It provides uniform load in the electricity net.
c. Due to three bus wires are in the RDP3 . The heating cable is more flat and increase transfer heat areas and energyeffciency.
Strengthen range is that ordinary rang add a oversheath and high strength machanical and corrosive-proof feature.
5、 产品应用场合 Application
RDP3 型三相恒功率电热带与RDP2 型单相恒功率电热带一样,能用于解决管道和阀门等的防冻和保温。具体应用场合也与RDP2 型单相带相同(详见RDP2 型单相电热带产品应用,见P6)。但需特别指出的是:当在长距离、大口径管道进行伴热保温时,采用三相带比单相带更经济、更合理、更能显示使用三相带的优越性。
RDP3 three phase heating cable is the same as RDP2 . It is suitable for freezing protection of long pipe and valve. It ismore reliable cost effective for long pipeline to use three phase heating cable.
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电伴热产品 Introduction
三、 RDP2-J4 型高温恒功率电热带 Hi-temp constant watt heating cable
母线bus wire电热丝高温复合绝缘层hi-tempheating elementinsulation耐高温防火玻璃纤维hi-temp fibreglassPFA护套铜编织层PFAcopper overbraidinsulationPFA护套PFA insulationRDP2-J4 型高温恒功率电热带,其工作原理,产品结构及应用与RDP2-J3 型恒功率电热带相同,所不同的是其绝缘材料采用了耐高温防水玻璃纤维和耐温高于F46的PFA氟塑料,流体维持温度可达180℃-205℃,它尤其适合沥青、重粘油管线伴热,该产品可用于工厂一区、二区爆炸场所。
RDP2-J4 Hi-temp heating cable properties is similar to RDP2-J3, The difference is that the insulation material is Hi-tempwater proof fiberglass and PFA fluoropolymer. It is suitable for industrial application where temperature excursons to 205℃or process temperature maintenance to 180℃~205℃. Particularly use in maintenance temp such as pipeline of Pitch,crude oil. It is approved for ordinary (non-hazardous) areas and division 1,2 hazardous (mixed gas) Class locations.
1、 型号含义 Type number nomenclature
RDP 2 (Q) - J4 -额定功率: W/m watt per meter
绝缘层材料代号insulation: J4防水玻璃纤维及-PFA氟塑料J4-Water-proof fiberglass and PFA fluoropolymerQ:加强型、普通型不注 Strengthen range (ordinary range no mark)2:芯线数2,单相220V工作电压 number of wires 2; voltage 220VRDP:并联型电热带 heating cable
例:RDP2-J4-40 : 表示绝缘材料为PFA氟塑料,功率为40W/m的高温恒功率电热带
Example: RDP2-J4-40: insulation material:PFA,40W/m Hi-temp constant heating cable
2、 产品规格及主要技术特性 Performance and rating data
表2-3
*流体最高维持温度: 是指管道内介质需要维持的最高工艺温度,一般不宜超过本表规定值。
*maximum maintenance temperature: maximum maintenance fluid flow temp in pipe not allow to exceed it
额定电压 Rated Voltage: 220V
常态绝缘电阻 normal insulation resistance: ≥20MΩ介电强度 dielectric test: -2000V 50Hz/1min
绝缘层材料 insulation material: F46 氟塑料 fluoropolymer最高耐温 maximum withstand temperature: 260℃防爆标志 explosion-proof marks: e ⅡT3防护等级 type of protection: IP54
尺寸(包括编织和外护套) Size (including braid & oversheath): 8.2×5.9mm
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电伴热产品 Introduction
四、 CRH型船用恒功率电热带 CRH marine constant watt heating cable
船用电热带的结构,外形尺寸和工作原理与RDP2和RDP3型电热带相同,其主要用于海洋船舶 、海上石油钻井平台 或其它具有海洋性恶劣环境条件的爆炸性气体场合。
CRH marine heating cable construction, dimension and principle is similar to RDP2 and RDP3 . It is suitable for use inoffshore, drillng platform and any areas having explosive gas.
1. 型号含义 Type number nomenclature
CRH (Q) -电压 voltage: V
额定功率 watt per meter: W/m
Q:加强型(普通型不注) Strengthen range (ordinary range no mark)CRH:船用恒功率电热带 marine heating cable
例e.g:CRH-40/220 : 表示单相普通型船用电热带,功率为40W/m single phase marine cable (ordinary range):40W/m
2. 规格和技术指标 Performance and rating data
表2-4
3. 产品特点 Production feature
船用电热带除具有RDP2型和RDP3型电热带的全部特点外,还具有防腐蚀性好、防霉菌生长、耐油、耐热老化性好、阻燃和绝缘更可靠等特性,它是在RDP2 型和RDP3型电热带基础上采用先进的工艺手段和严格的质量保证体系制造的高质量产品,每批产品均经国家船检机构检测认证。与船用电器附件配合使用,可在海洋船舶和工厂一区、二区爆炸性气体场合的T3 温度组别的恶劣环境中安全使用,防爆等级为“e Ⅱ T3”,防爆合格证证号:单相电热带GYB94389,三相电热带GYB94390。
Besides for all feature of heating cable(RDP2, RDP3 range), It has corrosive-proof, mould resistance, flame-retardantand insulation realizable, It is manufactured by anvanced technology and quality assurance. It is suitable for use in offshoreand division 1,2 and explosive gas(t3 group) in hazardous areas. Explosion-proof mark:“e Ⅱ T3”,Explosion-proof certificationof inspection: GYB94389(single phase cable) and GYB94390(three phase cable).
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电伴热产品 Introduction
五、 RDL-J6变功率电热带 Power-limiting heating cable
RDL-J6变功率电热带和恒功率电热带类似但具有一定的自控温特性,它能随着外界温度的升高输出功率降低;外界温度的降低其输出功率增高;其流体维持温度可达150℃,该产品可用于工厂一区、二区爆炸性气体混合场所。
Power-limiting cable combing the best features of self regulating and constant wattage construction. As the temperatureincrease. Causing power output to decrease, Maintenance fluid flow temperature range is up to 150℃, It is approved fornon-hazardous areas and division l, 2 hazardous(mixed gas) T3 class locations.
1、 型号含义 Type number nomenclature
RDL 2 (Q) - J6 -额定功率 W/m(环境温度为20℃) watt per meter
绝缘层代号: J6-PFA氟塑料 Type of insulation:J6-PFA fluorpolymerQ:加强型(普通型不注) Strengthen range (ordinary range no mark)
2:芯线数2,单相220V工作电压;3,380V工作电压 number of wires 2; voltage 220V 3; voltage 380VRDL:变功率电热带 power limiting heating cable
例e.g:RDL2-J6-40: 表示40W/m的变功率电热带。 40W/m power-limiting heating cable
2、 产品规格及主要技术特性 Performance and rating data
表2-5
*流体最高维持温度: 是指管道内介质需要维持的最高工艺温度,一般不宜超过本表规定值。
*maximum maintenance temperature: maximum maintenance fluid flow temp in pipe not allow to exceed it
额定电压 Rated Volts : RDL2 型220V RDL3型380V常态绝缘电阻 normal insulation resistance: ≥20MΩ介电强度 dielectric test: -2000V 50Hz/1min
绝缘层材料最高耐温 max withstand temperature: 260℃
尺寸(包括编织和外护套) Size (including braid & oversheath): RDL2:9.3×6.3mm RDL3:12×6.3mm
3、 功率、温度曲线图 Heat output curves
功率 (W/m)图2-1
温度℃11
电伴热产品 Introduction
六、 LT、HT型自限式电热带 LT HT Self regulating heating cable
母线bus wire发热芯heating core护套outer insulation铜编织overbraid加强护套oversheathLT、HT型自限式电热带的基带系我公司引进美国NELSON公司产品,NELSON公司是世界著名电伴热产品制造厂商之一,本产品采用国际IEEE标准制造,产品水平据国际一流。
本自限式电热带功率衰减小,使用寿命长。它能根据伴热温度调正其输出功率,这种自控温特性在产品长度上处处存在,即使是电热带交叉安装,也不会产生交叉点过热。它适用于较复杂热场的伴热系统。
LT、HT型自限式电热带适用的最高温度分别为85℃和185℃,最高流体维持温度分别为65℃和120℃的场合,并且可根据管道长度任意切割,正因为它的自控温特性,所以伴热的热场比较均匀。它在工业上应用广泛,主要适用于电厂、海洋平台、石油化工厂、高层建筑的配套设施以及食品加工等,它们分普通型(/TC-),加强型(/T-)两种。加强型适合于有腐蚀性的场合。
The products of based strip are imported from NELSON company in USA, one of the major electric surface heatingcompanies in the world. The products are manufacutred according to IEEE international of standard, The products qualitycome to the recently world advanced stage.
NELSON’s products power drop(self-regulating) is very small and longlived, It can auto-adjust the power output tothe varying conditions along the pipe. Self regulating properties occurs at every point along the length of cable, The selfregulating effect allows the cable to be overlapped without creating hot spots or burnout. It is suitable for requiring heating-trace in comprehensive heat field.
LT(HT) is suitable for industrial applications where temperature excursions to 85℃ (185℃) or process temperaturemaintenance to 65℃ (120℃) may be experienced and can be cut at any point to fit pipework, Owing to self-regulatingproperties. It produce a uniform heat field. It has been widely used in power stations, off-shore installations, petrochemical,building services and food processing, It has ordinary range (/TC-) and strengthen range (/T-). strengthen range is suitablefor use in corrosive areas.
1、 型号含义 Type number nomenclature
/
额定功率 watts : W/m (10℃)
编织材料 TC : 镀锡铜丝编织 (普通型) Tinned copper braid (ordinary range)
T : 镀锡铜丝编织加外护套 (加强型) Tinned copper braid and over jacker (strengthe range) 自限式电热带SR LT: 低温型 Low-temp range HT: 高温型 High-temp range
例e.g:LT/TC-30:220V 30W/m : 低温普通型自限式电热带。220V 30W/m Low-temp self-regulating cable
HT/T-50:220V 50W/m : 高温加强型自限式电热带。220V 50W/m High-temp self-regulating cable
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电伴热产品 Introduction
2、 技术指标 Rating data
额定电压 service voltage: 220V介电强度 dielectric test: 2.5kv/min绝缘电阻 insulation resistance 〉20MΩ
最高耐温 max withstand temperature: LT: 85℃ HT: 185℃
尺寸(包括编织和外护套) Size : 11.7×5.4mm(LT规格) 10.3×5mm(HT规格)
注: LT加强型的接线盒请选用CH型系列接线盒
最小弯曲半径 minimum bend radius: 19mm最低安装温度 min install temp: -40℃
最高维持温度 max maintenance temperature: LT: 65℃ HT: 120℃额定发热量 rated power output(10℃) LT: 30W/m,25W/m,15W/m
HT: 60W/m,50W/m,40W/m,30W/m,25W/m,20W/m,10W/m
3、 热力值曲线 Heat output curvesWatts per metre heat outputWatts per metre heat output输出功率W/m图2-2 图LT型
输出功率W/m图2-3 图HT型
4、 断路器(熔丝)规格 Fuse/circuit breaking sizing
(LT型)
表2-6
(HT型)
表2-7
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电伴热产品 Introduction
七、 RDC型串联电热带 RDC series resistance heating cable
加强层 oversheath铜编织 overbraid外护套 outer insulation复合绝缘 composite发热芯 heating element
RDC串联型电热带是一种由芯线作发热体的电伴热产品,即在具有一定电阻的芯线上通过电流,芯线就发出焦耳热,由于芯线单位长度的电阻和通过的电流,在整个长度上是相等的,不会如并联型电热带随着使用长度的增加造成尾端功率降低,因此它主要适用于长距离管线的伴热保温,用一个电源点供电,可进行最长达3.6公里的管线伴热,使用本产品,本公司技术部门可提供咨询服务,以确认设计。
RDC series resistance heating cable is based on bus wires as to heating element. A current flowing in bus wiresgenerate heat energy. Equal power output occurs at every unit the length of cable. but the parallel type heating cable poweroutput decrease as length increase. RDC cable can provide heating trace for pipe 3.6kms long with one power supply point.Our technical department can provide desigh and service.
1、型号含义 Type number nomenclatureRDC (Q) - J -芯线截面bus wire:mm2
绝缘层代号 insulation type: J3-F46氟塑料 J6-PFA 氟塑料
Q:加强型 普通型不注 strengthen range (ordinary range no mark)芯线数代号number of bus wire: 1-单芯、 2-二芯、 3-三芯RDC:串联式电热带series resistance heating cable
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电伴热产品 Introduction
2、 产品规格及主要技术指标 Production range and specification
表2-8
注: 我公司可为用户设计、制造非标串联电热带。欢迎向公司技术部门咨询。
NOTE: we can provide design and manufacture for no-standard series heating cable.
额定电压 rated voltage: 220V、380V、660V、1100V绝缘电阻 insulation resistance ≥750MΩ/Km
介电强度 dielectric test: 2×额定电压 (rated voltage) +2500V绝缘最高耐温 max withstand temperature: J3-205℃,J6-250℃最低安装温度 minimum install temperature: -50℃
3、 冷端连接 Cold Lead Assembling
为提高串联型电热带的使用寿命,在电源接线处常采用冷端接线的方法。具体使用如下:
a. 剥去串联型电热带的内外护套和绝缘露出发热芯线,用铜接头与冷端导线(预先剥去绝缘层)进行压接。b. 用3M带进行绕包,把编织层留在外面供接地使用。
c. 再分别套上四层收缩套管,用电吹风机加热热收缩管套使其紧包在接头上。根据实际的电流规格选用不同的冷端型号,见下图表
Choose the suitable kit type according to heating circuit rated current(see table below).
DCBA冷端 Cold leadd铜接头 Copper joint串联电热带Series Heating Cable冷端连接最高耐温 +120℃ (基于维持温度在80℃以下使用)Cold joint for temperature up to +120℃
表2-9
注: 冷端CJ在维持温度超过80℃以后,表中单位面积的载流量须相应分别减少。If the maintaining temp exceed 80℃ (CJ), please contact us.
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电伴热产品 Introduction
八、 集肤效应电伴热系统 Skin effect heating system
集肤效应伴热系统是一种基于电流的集肤效应及邻近效应原理的电伴热系统。所谓集肤效应,就是交流电流通过碳钢导体时电流逐渐趋肤在导体表面的一种现象,而邻近效应是一对通以反向等电流导体间的一种电磁现象,在加热管中的电缆和加热管间通以电流时,加热管上电流逐渐趋肤在加热管内壁,而正是这薄薄的内壁产生的焦耳热来满足伴热的需要。
下图是一个基本集肤效应伴热电路,由一个隔离变压器,初级和次级电流熔断器,接触器及一个温控组成,如需考虑电网的三相平衡,可实行多相电源供电,或采用三相变单相的变压器。
Principles of skin effect and proximity effect are an alternating current phenomena whereby Ac current flows in theouter surface of a carbon steel conductor. Proximity effect is an electromagnetic force whereby equal currents in oppositedirections attract. By placing the electric cable inside of the heat tube. The current is drawn to a thin section of the heat tubeinnerwall. Heat generated from the current is dispitched through the heat tube wall and into the carrier pipe by conduction.
The power circuit for a basic single-phase load SKIN EFFECT CURRENT TRACING system consist of a transformerfor isolation and specific voltage. Primary and secondary current protection an operating contactor and a temperaturecontrol device.
电源to supply断路器circuit breaker接触器contactor温控器temperaturecontrol变压器transformer传感器sensor图2-6 系统安全接地示意图System safe ground diagram
图2-7 基本电图basic circuit
常规符合NEC426.427,可根据用户需要进行设计,仅需电源一个供电点,可进行长距离管道伴热,功率因素高,热效率高,对于相关工程应用,可根据CAD设计,维护及修理方便。
集肤伴热系统有效维持温度可达230度,它与电热带相比最大的特点是伴热温度高,功率密度大,一个电源点的伴热距离最长可达24Km。系统简单、可靠、经济,适用于长输管线、大口径、伴热温度较高的场合。使用本系统,本公司可提供咨询、设计、生产、施工等全方位服务。
Custom designed and supplied in accordance with NEC426.427 and design according to application requirements:Only one power feed point required for long pipeline. Provided CAD design, relating to your appliance. Easy to repair/minimum maintenance, The effective maintenance temperature rang for SKIN EFFECT CURRENT TRACING is 0-230℃, Ithas advantage over heating cable in high maintenance-temp and power density, One power feed point for pipeline up to24Km. Maintenance system is reliable and cost-effective. It is suitable for long pipeline and high maintenance-temp fluid.We can provide consulting service, design and manufacture in this system.
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电伴热产品 Introduction
加热管道heat tube典型的是1/2”-2”碳钢管焊在被伴热管道上typically 1/2Ó-2Ó carbon steel pipe is welded the carrier橡胶垫片rubber gasket被伴热管道carrier pipe防护层weather barrier电源接线盒power connection防护管conduit接地to ground电源引接线power leads终端接线盒terminator-box17
耐高温电缆hi-temp cable保温层insulation电伴热产品 Introduction
九、 LDB型挠性电热板 LDB Flexipanel
LDB型挠性电热板是用于油罐,槽池和容器的电伴热产品,按“增安型e”防爆要求设计制造,能在工厂一区、二区爆炸性气体T3组场所使用。
LDB Flexipanel is ideal for use in maintaining temp of oil tank, pool and vessel. It is designed and manufacturedaccording to increased-safety explosion-proof requires and approved for division 1,2 and explosive gas(T3 group) in hazardousareas.
1、 型号含义 Type number nomenclature
LDB -规格代号range A,B,C挠性电热板 Flexipanel
例: LDB-B表示:B型挠性电热板。 E.g:LDB-B,B range flexipanel
2、 产品结构与工作原理 Construction and principle
挠性电热板由耐热橡胶,均匀分布的金属发热元件,接地金属网和防爆电源接线盒等部分组成。当接通电源,均布着的电热元件通过耐热橡胶发散热量。
The Flexipanel is made of hi-temp rubber, heating element, grounding grid and power connection kit. It can be producea uniform heat field.
产品结构示意图 Construction diagram:
电气绝缘 electric insulation接线网 grounding grid发热元件 heating element
电源引线 power lead
图 2-8
挠性电热板结构图
construction diagram
3、 产品规格及技术指标 Performance and rating data
表2-10
额定电压 rated voltage: -220V介电强度 dielectric test: 1600V/min绝缘电阻 insulation resistance〉50MΩ
罐体最高维持工作温度 max maintenance temp: 120℃产品最低安装环境温度 min install temp: -30℃产品最高耐温 max withstand temp: 230℃
产品平均表面负荷 average surface power: 0.31W/cm2防爆等级 explosion-proof class: e Ⅱ T3
防爆合格证 explosion-proof certification of inspection: GYB95144最小弯曲半径 min bending radius: 0.7m
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电伴热产品 Introduction
4、 产品特点 Products feature
a. 重量轻、安装方便:装一块挠性电热板只需20分钟;老设备改造,不必破坏容器原有的全部保温层,仅需在粘贴部位打开部分保温层即可。
b. 热效率高:因为挠性电热板紧贴罐体表面,热传导好。
c. 适应性强:挠性电热板对容器形状的适应范围较广,且不必对容器作改造(如打孔等)。d. 耐热耐寒性好:既维持容器120℃的温度;又能在-30℃低温时仍保持挠性。e. 能在户内、户外和工厂一区、二区爆炸性气体场所使用。
a. Installation easy and weightlight: Installation of Flexipanel requires approximately 20minutes. Installing the heaterdoes not require total removal of tank Insulation.
b. High energy efficient: It is pressed on the vessel firmly and heat transfer is excellent.c. High suitability: It is suitable for any shape vessel.
d. Cold-resistant and heat-proof excellent: Max maintenance temp of vessel up to 120℃, It remains flexible at temperaturedown to -30℃.
e. It is approved for indoor or outdoor and division 1,2 hazardous gas locations.
5、 产品应用场合 Application
挠性电热板可广泛应用于石油、化工、食品和机械等行业的罐体、反应塔、馏化塔及有关容器的加热、保温和防冻。Flexipanel is widely used in tank, reaction tower and freeze protection.
注重: 如果罐体内的介质是不耐高温的产品,或罐体是非金属材料,请勿随便用挠性电热板,若要使用,须与公司商磋。CAUTION: If flexipanel is to be installed on temperature sensitive non-metallic vessels, or if product contained in thevessel is highly temperature sensitive, Please contact our technical department.
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电伴热产品 Introduction
十、 短路加热法 Impedance heating system
短路加热法是各种电伴热系统中的一种。它不是采用加热电缆,而是利用自身的机械设备产生热来维持过程温度的需要。短路加热法有许多优点:
a. 热场均匀,无过热点,对介质不会生产任何影响。
b. 对于已保温的管道需伴热的话,不需拆除保温层,节省了大量的费用。c. 几乎不需要任何维护。
d. 由于靠设备自身发热,寿命很长。e. 安装简单方便,大大节约安装费用。f. 控温范围宽。
The Impedance system is one of the various of electric heating system.
Does not utilize heating; instead it utilizes it’s own mechanical equipment to carry the power necessary to maintain therequired process temperature.
There are many advantage in using Impedance heating sysytem. Some of advantage:
a. Uniform heat fieid, no hot spot and no influence to the fluid.b. Using for already insulated, without having to do with the insulation.c. Routine maintenance is eliminated.
d. Long ages due to utilize the equipment to produce heat.e. Installation is simple and only need a few basic components.f. Wide temperature range.
1、 短路加热法的原理 Principle of Impedance system
电源电缆 power cable磁流 magnetic flux保温层thermal insulation
管道pipe
介质fluid短路加热是采用低电压大电流方式。通俗而言就是把管道作为一个加热电阻,两端加一电压使管道发热(见上图)。具体工作原理要比其它伴热产品复杂一些。但一般来说,短路加热法的来源主要包括以下三部分:
a. 管道象传统的电热丝一样发热,其阻值取决于本身材料、长度及壁厚;如管中介质为导电性介质,也要产生部分热量。b. 由于输入电缆靠管道很近,而通过的电流又很大,一般为80A-800A,电缆周围会产生很强的磁场,管道受磁场的作用会产生感应热。
c. 管道中磁滞现象,产生磁滞损耗,也产生部分热。
由于短路加热涉及的参数很多,计算复杂。我公司开发的短路加热设计软件为用户在功率设计上带来极大的方便。
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电伴热产品 Introduction
The Impedance heating is low volts big current heating way. The explanation of how Impedance heating work is a bitmore complex, tradtionally electric heat is generated by pass current. heat is generated by combing three different effects.
a. the pipe act resistor. the resistance of pipe depends upon its length, composition and wall thickness. If the materialbeing transported through the pipe is electrically conductived. It also represents a portion heat.
b. Set up a significant magnetic field around the cable when a big current passes it through. The magnetic fieldinteracts with pipe, producing the second component of heat.
c. The electrical inertia of the pipe to these changes produces a hysteresis effect, which is the third source of heat in thepipe.
The recently software, which is based on short circuit heating system, will further help our clients to calcuate power andselect correct cable and accessories.
2、 安装示意 Install diagrammatic
短路加热的安装方式有很多种。有两点法、三点法和平行法等多种安装方法。下页是两点法最典型的例子。
但在实际运用中,三点法使用的最普通、最安全,因为它不需要复杂的辅助元件,仅需要一些电气接线块和热电偶传感器。
There are three basic types of Impedance heating connection, END-FEED,MID-PIONT and PARALLEL PIPE andPIPE. The following draw is typical END-FEED connection.
In practice, MID-POINT is the most typical connection. Due to not need complexity components and without disturbingexisting thermal insulation. Only need a few basic components such as terminal plates and thermocouple sensor.
控制屏 control panel变压器 transformer电气接头电气接头ElectricalConnection在管道中间电气连接CableElectricalConnection法兰Flanges进口 lnletPipe出口 Outlet图2-9 三点法
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电伴热产品 Introduction
配电柜 Control Panel电力电缆Power Cable进口INLET热电偶引接线Thermocouple Leads(attach to control panel)变压器Transformer Panel热电偶Thermocouple Connection绑带Strap绝缘外壳Insulation Jacket标准管道Standard Pipeline电缆接线板 Cable Lug出口 OUTLET绝缘板lsolator Gasket密封圈Steel Washer绝缘螺丝lsolator Bolt
图2-10 两点法
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电伴热产品 Introduction
十一、 融雪电缆 Snow and Ice Melting
SIM融雪电缆的结构与单根串联型电缆相类似,结构上的不同之处是在外护套上还加有一层不锈钢编织以加强其在道路、桥梁等场合使用的机械强度。它采用了新颖合金材料作为发热元件。它现被广泛用在机场跑道、桥梁等场合的防冻、防雪。并可作为电影院、体育馆等的取暖设备。
The construction of snow ice melting cable is simiar to series cable. The difference construction is addition stainlessbraiding on the oversheath. Consequence the mechanical strength shall be improved. It has been widely used for meltingsnow and ice on aircraft road, bridge and railway as well could be used comfort in cinema, auditorium and building.
1、 型号含义 Type number nomenclatureSIM / ST -20℃环境下每公里电阻Ω/Km不锈钢编织 Stainless braid融雪电缆 Snow & ice melting
2、 技术参数 Technical data
表2-12
根据当地的最低环境温度的不同,应选用不同的融雪功率
According to min ambient temperature, Various power outputs should be selected.
表2-13
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电伴热产品 Introduction
3、 应用须知 Notice
a. 在电缆敷设的上下两层,应采用纯水泥,不应夹杂有石块避免对电缆的损伤。b. 根据路面负载的大小情况,其上下层水泥厚度应作相应变化。c. 避免融雪电缆直接与电源连接,应通过冷端连接线。d. 所有的电缆是根据现场情况或工程图纸在工厂预制。e. 如配有融雪传感器,电缆加热启动和停止能自动完成。
4、 尺寸示意 Size diagrammed
融雪电缆Snow melting cable热线与冷端接头 connector (hot/cold)冷端 cold lead
间距 100-150mm图 2-11
space5、 安装示意 Install diagrammed
30-5020-5030-50混凝土 concrete
融雪电缆 Cable钢丝网 wire mesh
120-130混凝土 concrete
图 2-12
图 2-13
融雪传感器 snow sensor
6、 典型应用 Typical Application
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电伴热产品 Introduction
十二、 MI 电缆 Mineral cable
825 合金 Alloy 825
发热元件 heating elements
氧化镁粉 Magnesium oxide
MI电缆是一种以金属作为外护套,电热材料作为发热元件,氧化镁作为绝缘的特殊电缆。电流通过电缆的串联式电阻发热芯上产生热量,因此发热均匀,单位长度上的发热量随着工作电压及发热芯的截面及电缆的长度不同而不同,我公司现有两大类的MI电缆,一类是单芯电缆,另一类是双芯电缆;以上两类产品均从美国NELSON公司引进。金属外护套的材料为825合金,最高伴热温度为590℃。MI电缆具有耐高温、防水、防爆、不老化、机械强度高、安全可靠等特点,可广泛应用在石油、化工、冶金、交通、商业、农业和建筑部门; 在工业上的应用它主要具有以下优点:
暴露温度高电缆机械强度高耐腐蚀
维持温度高整个长度发热均匀
直径小、可弯成任何形状,安装方便
功率输出高寿命长
适用于融雪工程、室内取暖以及容器及管道的加热和保温。
Mineral insulated cable is a metal sheathed cable that uses a metallic conductor as heating element. The conductor iselectrically insulated from the metal sheath with magnesium oxide. Ml is a series resistance heater that generates heat bypassing current through the electrical conductor. Power output per unit length of the cable therefore varies with the appliedvoltage and resistance of the conductor.
1、 型号含义 Type number nomenclature
冷端长度cold section length(dm)发热长度 Hot section length(m)
电缆直径 Cable diameter B 或 K 类B:8.2mm K:4.8mm电缆代码 conductor section from table 见电缆代码接线形式From A 型或E 型
2、 接线方式: Form Range
A型 Form A
发热部分
hot section冷端部分cold section30cm引接线pigtailE型 Form E(单芯MI-1-conductor)
30cm引接线pigtail
冷端部分cold section发热部分hot section冷端部分cold section30cm引接线pigtail25
电伴热产品 Introduction
E 型 E Form (两芯MI 2-conductor)
30cm引接线pigtail冷端部分cold section发热部分hot section冷端部分cold section30cm引接线pigtail3、 电缆代码 Cable specification
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电伴热产品附件 Accessories
一、 通用隔爆型接线盒 General Ex-proof power connection box
通用隔爆CH型接线盒,是电热带的配套附件,本接线盒按隔爆型防爆型电器要求设计制造,防爆标志: “dllBT4”。与电热带配套适用于工厂一区、二区爆炸性气体混合物T4组场所使用。它可作电源与一根或二根电热带的连接(作为单、双向电源接线盒之用),二根或三根电热带之间的连接(作为直、T型接线盒之用),并可方便地和温控器连接。其外壳为铝合金,具有重量轻、机械强度高、防爆能力强的特点。
CH range general explosion-proof connection box is necessary accessories of heating cable. It is designed andmanufactured according to explosion-proof electrical-equipment requires, explosion-proof mark:“dllBT4”. The system(include heating cable) is approved for division 1,2 and explosive gas (T4 group) in hazardous areas. It can be used aspower connection box (each, both direction), Tee connection kit and splice connection. It is easy to connect to temperaturecontroller, The enclosure is aluminum-alloy with weight-light, corrosive-proof and high mechanical strength feature.
1、 主要技术性能指标 Performance and technical data
额定电压 rated voltage: 660V/380V额定电流 rated current: 40A
防爆标志 explosion-proof class: dIIBT4防护等级 type of protection: IP56
电缆密封圈内径 sealing grommet inner diameter of cable: φ14、 φ20防爆合格证号 explosion-proof certificate of inspection: GYB99324
2、 产品结构及外形 Construction and size
1”进孔线1Óinlet screw接线块connection block3/4”进孔线3/4Óinlet screw盒盖cover1”进孔线1Óinlet screw管道pipe喉卡pipe clamp电热带heating cable
图 3-127
电伴热产品附件 Accessories
3、 使用示意 Schematic diagram
动力电缆power cable动力电缆power cable接温控器(可选)temp-controller电热带heating cable接温控器(可选)temp-controller电热带heating cable图 3-1 作单向电源接线盒(one direction power connection box)图 3-2 作双向电源接线盒(both direction power connection box)电热带heating cable电热带heating cable电热带heating cable图 3-4作直型接线盒(one direction power connection box)图 3-5 作T型接线盒(one direction power connection box)4、 注意事项 Cautiona. 发现接线盒外壳有变形、裂痕或损坏,应停止使用。
b. 安装时应防止电热丝,外编织铜丝及芯线之间的短路及电气间隙的减少。c. 应按电热带的型号选用所附适当的密封圈。d. 不用的进线孔应用所附钢板堵住。
a. If the connection box has been out of shape, crack and damage. Plsese replace it.
b. Avoid shorting circuit between heating element, overbraid and bus wire, And decreasing electric gap.c. Select proper sealing grommet according to type of heating cable.d. Stop up unused conduit entry hole with gasket.
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电伴热产品附件 Accessories
二、 通用增安型接线盒 General increased-safety power connection box
通用型增安接线盒NCH是按照增安型电器要求进行设计制造。防爆标记为“eⅡBT4 ”,与电热带配套后适用于工厂一区、二区爆炸性气体混合物T4组场所使用。它可做电源与一根或二根电热带的连接(作为单、双向电源接线盒之用),二根或一根电热带之间的连接(作为直型,T型接线盒之用),并可与方便地与温控器连接。其外壳采用铝合金材料,采用压铸形式制造,外喷涂耐腐蚀粉末材料,银灰颜色,具有重要轻,机械强度高和防爆能力强等特点。
General increased-safety power connection box is designed and manufactured according to increased-safety electrical-equipment requires, ex-proof mark is [de ⅡBT4, The snstem is approraled for divesion 1, 2 for ] explosive gas (T4 group)in hazardous areas. It can be used as power connection box (each, both direction), Tee connection kit and splice connection.It is easy to connect to temp-controller, The enclsoure is aluminum-alloy with weight-light, corrosive-proof and high mechanicalstrength feature.
1.型号含义 Type number nomenclature:
NCH-1/1: 单向电源接线盒 One-way junction box1/2: 双向电源接线盒 Two-way junction box1: 中间接线盒 Splice connection box2: T型接线盒 T splice connection box
2.主要技术性能指标 Performace and technical data:
额定电压 Rated volts: 660V, 380V额定电流 Rated current: 40A防爆标志 Ex-proof mark: eⅡBT4防护等级 Type of protection: IP65
适合电缆线径 Cable ourter diameter: φ18~φ25防爆合格证 Ex-proof certification: GYB01521
3.产品结构及外形 Shape and Size:
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电伴热产品附件 Accessories
4.使用示意 Schematic diagram
接线盒接线端子动力电缆进口热缩管热敏胶带电热带钢带锁紧螺母盖接线盒接线端子动力电缆进口锁紧螺母热敏胶带电热带盖热缩管钢带图3-6 作单向电源接线盒
(one direction power connection box)
图3-7 作双向电源接线盒(both direction power connection box)
接线盒接线端子锁紧螺母热敏胶带电热带接线盒接线端子锁紧螺母盖热缩管热敏胶带电热带盖热缩管钢带钢带图3-8 作直型接线盒(splice connection box)
图3-9 作T型接线盒(Tee splice connection box)
5.注意事项 Caution:
a.发现接线盒外壳有变形、裂痕或损坏,应停止使用。
b.安装时应防止电热丝、外编织铜丝及芯线之间的短路及电气间隙的减少。c. 应按电热带的型号选用所附适当的密封圈。d. 不用的进线孔应用所附的钢板堵住。
a. If the connection box has been out of shape, crack and damage. Please replace it.
b. Avoid shorting circuit between heating element, overbraid and bus wire, decreasing electric gap.c. Select proper sealing grommet according to type of heating cable.d. Stop up unuse conduit entry hole with gasket.
30
电伴热产品附件 Accessories
三、 防爆温度控制器 Ex-proof temp-controller
防爆温度控制器用于控制被伴热的介质温度,本温度控制器有BJW51A,BJW51型两种型号,它们都是按防爆电器要求设计和制造,防爆标志:“de Ⅱ BT4 ”;其中BJW51A其外壳为铝合金,外表喷塑,具有重量轻、机械强度高、防腐能力强等特点。BJW51型外壳为高强度塑料。
Explosion-proof temp-controller is used to control temp of fuild flowing in pipe, the temp-controller has two range(BJW51A range and BJW51 range), It is designed and manufactured according to explosion-proof electrical equipmentrequires, explosion-proof mark is deIIBT4, the enclosure of BJW51A is aluminum-alloy with weightlight, corrosive-proof,high mechanical strength feature, the enclosure of BJW51 is high-strength plastic.
1、 型号含义 Type number nomenclatureBJW 51
最高控制温度Max control temperature设计序号Design code工厂用 Use in factory
防爆温度控制器 Explosion-proof temp-controller
2、 主要技术性能指标 Technical data
额定电压 rated voltage: -220V额定电流 rated current: 15A
调温范围 temperature range: 0~85℃、10~120℃、30~150℃控温精度 temperature control percision: ±4℃通断差动 tolerance: ≤4℃
控制电缆密封圈内径 sealing grommet inner diameter of cable: φ14mm防护等级 type of protection: IP54
防爆合格证号 explosion-proof certificate of inspection: GYB94391
3、 产品结构及外形 Construction and size图 3-10 BJW51A 型图 3-11 BJW5 型31电伴热产品附件 Accessories
4、 使用示意 Schematic diagram
电源Power SupplyN温度传感器temp-sensing温度控制器thermostatNOCNC电热带 heating cable图 3-12如果负载电流超过15A,应选用接触器进行控制。If the load excees 15A, The load must be controlled via contactor.电源Power SupplyNNOCNC线圈 coil温度传感器 temp-sensing温度控制器 thermostat电热带 heating cable电热带 heating cable电热带 heating cable图 3-13
5、 注意事项 Caution
如发现接线盒外壳有变形、裂痕或损坏,应停止使用。
If the connection box has been out of shape, cracked and damaged. Please replace it.
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电伴热产品附件 Accessories
四、 增安型电源接线盒 Increased-safety power connection box
增安型防爆电源接线盒用于电源线与电热带在防爆区域的连接。本电源接线盒按增安型防爆电器要求设计和制造,防爆标志: “e Ⅱ T4”,与电热带配套后适用于工厂一区、二区爆炸气体混合物T4组场所使用。其外壳为高强度塑料。 ZDH-2适用于电源与二根电热带连接(双向输出)。
Increased-safety power connection box is used for connecting heating cable to power wrie in hazardous areas. It isdesigned and manufactured according to increased-safety explosion-proof electrical equipment requires. Expolsion-proofmark is:“e Ⅱ T4”, The system (include heating cable) is approved for division 1,2 and explosive gas (T4 group)in hazardousareas. The enclosure is high strength plastic. ZDH-2 range is suitable for connecting both heating cable to power wire (bothdirection output).
1、 型号含义 Type number nomenclature
ZD H 2
密封圈代号type of sealing grommet电源接线盒 power connection box增安型 Increased-safety type
例:ZDH-2型表示:单点电源、输出二根电热带的增安型防爆接线盒
such as: ZDH-2 range: One power feed point connection box (both direction output)
2、 主要技术性能 Technical data
额定电压 rated voltage: -220V/380V额定电流 rated current: 10A电缆线嘴螺纹 inlet screw: G1/2”防爆标志 explosion-proof make: e Ⅱ T4防护等级 type of protection: IP54
橡胶电缆密封圈直径 sealing grommet inner diameter of cable: 10.7mm防爆合格证证号 explosion-proof certificate of inspection: GYB94394
3、 产品结构及外形 Construction and size电缆进线孔Cable Conduct电热带heating cable卡箍Pipe Clamp 图 3-14ZDH-2 电源接线盒外形及安装图Installation diagram of ZDH-2
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电伴热产品附件 Accessories
4、 使用示意 Schematic diagram
盒盖 cover盒盖垫 rubber gasket盒体 connection kit垫板 gasket压板 pressure plate密封圈 sealing grommet垫片 gasket中间座 middle base固定座base电热带heating cable图 3-15 ZDH-2不同规格型号的电热带由于尺寸不同,所以应配用不同内孔的专用橡胶密封圈。各种规格型号电热带的专用密封圈请按表3-1选用。
Please select a right rubber sealing grommet according to the size of heating cable.
表3-1
5、 注意事项 Caution
a. 发现接线盒外壳有变形、裂痕或损坏,应停止使用。
b. 安装时应防止电热丝、外编织铜丝及芯线之间的短路及电气间隙的减少。c. 应按电热带的型号选用所附适当的密封圈。d. 不用的进线孔应用所附钢板堵住。
a. If the connection box has been out of shape, crack and damage. Please replace it.
b. Avoid shorting circuit between heating element, overbraid and bus wrie, And decreasing electric gap.c. Select proper sealing grommet according to type of heating cable.d. Stop up unused conduit entry hole with gasket.
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电伴热产品附件 Accessories
五、 增安型中间接线盒 Increased-safety splice connection kit
增安型防爆中间接线盒用于防爆区域电热带与电热带的连接,以增加电热带的长度或用在同一管线上配用不同功率的电热带及三叉管等较复杂的场合。它有ZZH型防爆直型接线盒(俗称“二通”),ZTH型防爆直型接线盒(俗称“三通”)两种形式,它们都按“增安型”防爆电器设计制造。防爆标志“e Ⅱ T4”,与电热带配套后适用于工厂一区、二区爆炸性气体混合物T4组场所。其外壳为高强度塑料。
Increased-safety explosion-proof splice connection kit is used for connecting two pieces of heating cable in order toprolong heating cable length or connect two difference power heating cable on the pipe. ZTH is used for tee joint in complexareas. ZZH local name is splice joint and ZTH(tee joint). It is designed and manufactured according to increased-safetyexplosion-proof electrical equipment requires. Explosion-proof mark is “e Ⅱ T4” The enclouse is high strength plastic.
盖 cover端盖pressure cover橡皮垫 rubbergasket密封圈sealing grommet盒体 body1、 型号含义 Type number nomenclature
ZZH -密封圈代号type of sealing grommet增安直型接线盒 connection box
ZTH -密封圈代号type of sealing grommet增安“T”接线盒 connection box
2、 主要技术性能 Technical data
额定电压 rated voltage: -220V/380V额定电流 rated current: 10A
防爆标志 explosion-proof make: e Ⅱ T4防护等级 type of protection: IP54
防爆合格证证号 explosion-proof certificate of inspection: GYB94383
3、 产品结构及安装示意 Construction and schematic diagram
中间(直型)接线盒的连接35
多余剪掉剪掉图 3-16T型接线盒的连接剪掉正面连接同剪掉直型接线盒反面图 3-17剪掉此中间接线盒(包括T型),当用于三相电热带连接时,一方面须注意选取大号的密封圈,另一方面,端子3也当作负载接线用,编织屏蔽在接线盒之外进行连接。
4、 注意事项 Caution
a. 发现接线盒外壳有变形、裂痕或损坏,应停止使用。
b. 安装时应防止电热丝、外编织铜丝及芯线之间的短路及电气间隙的减少。c. 应按电热带的型号选用所附适当的密封圈。d. 不用的进线孔应用所附钢板堵住。
a. If the connection box has been out of shape, crack and damage. Please replace it.
b. Avoid shorting circuit between heating element, overbraid and bus wires, And decreasing electric gap.c. Select proper sealing grommet according to type of heating cable.d. Stop up unused conduit entry hole with gasket.
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电伴热产品附件 Accessories
六、 防爆终端接线盒 Ex-proof End termination kit
防爆终端接线盒又称终端封头,用于电热带的末端,使它与外界可靠隔绝。终端接线盒有“增安型”和“隔爆型”两种,防爆标志“e Ⅱ T4”和“d Ⅱ T4”,适合全天候条件和石油、化工等工厂一区、二区爆炸气体混合物T4组场所使用。ZZF型外壳材料为高强度塑料,与Z系列接线盒配套使用。 CZF型外壳材料为铝合金,与C系列接线盒配套使用。
Explosion-proof end termination kit that is sealing end. It is applied at the end of heating for isolating cable fromsurroundings, With explosion-proof range and increased-safety range, explosion-proof mark are “e Ⅱ T4”and “d ⅡT4”. It is approved for weatherproof and division 1,2 and explosive gas(T4 group) in hazardous areas. The enclosure ofexplosion-proof is aluminum-alloy and that of safety range is high strength phasic.
1、 型号含义 Type number nomenclature
ZZF -密封圈代号type of sealing grommet增安型终端封头 sealing-end
CZF -密封圈代号type of sealing grommet
隔爆型终端封头 explosion-proof sealing-end
2、 主要技术性能 Technical data
额定电压 rated voltage: -220V/380V防爆标志 explosion-proof make: e Ⅱ T4防护等级 type of protection: IP54
防爆合格证证号 explosion-proof certificate of inspection: GYB94392
3、 产品结构及安装示意 Construction and schematic diagram
螺丝Screw盖帽 Locknut密封圈 Sealing grommet尾端体 End body密封圈 Sealing grommet盖帽 Locknut电热带heating cable电热带heating cable图 3-18 ZZF 型
图 3-19 CZF 型
4、 注意事项 Caution
a. 发现接线盒外壳有变形、裂痕或损坏,应停止使用。
b. 安装时应防止电热丝、外编织铜丝及芯线之间的短路及电气间隙的减少。c. 应按电热带的型号选用所附适当的密封圈。
a. If the connection box has been out of shape, crack and damage. Please replace it.
b. Avoid shorting circuit between heating element, overbraid and bus wire, And decreasing electric gap.c. Select proper sealing grommet according to type of heating cable.
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电伴热产品附件 Accessories
七、 铝胶带 Aluminum tape
铝胶带系薄铝质带涂复特殊的胶粘剂后所形成的一种胶粘带。该带宽50mm,厚0.5mm,在电伴热系统中主要用于固定电热带,固定温控器的毛细管和感温包,或者用于挠性电热板的辅助固定。其作用除能方便电伴热产品安装固定外,主要是能增大散热面,有利于热传导。正确使用铝胶带是体现电伴热产品优越性的重要一环。考虑到安装损耗,铝胶带的长度一般为所购电热带长度的1.1倍,以满足安装需要。
Aluminum tape is special tape that back of aluminum foil isapproved adhesive, This 50mm wide and 0.5mm thickness aluminumtape is used to attach heating cable and thermostat sensing bulbs topipe or attach flexipanel to vessel, Except for bindng heating cable, Itis also used to heat sink of cable and increase heat transfer.Considering of installation consume, Aluminum tape is 1.1 times lengthof cable according to require.
电伴热产品附件 Accessories
八、 耐热压敏铝胶带 High-temperature fiberglass tape
耐热压敏胶粘带又称固定胶带,是在玻璃纤维带基础上涂复特殊粘剂后形成一种胶粘带,该带宽15mm,厚0.2mm,最高耐温可达200℃。在电伴热系统中,电热带安装后,用该耐热压敏带每0.8m沿管道径向将电热带固定牢,其配备长度视伴热管线外径和长度而定。
This 15mm wide and 0.2mm thickness(withstand temperature200℃) high-temperature fiberglass tape is used to fasten the cable topipe. It is a tape that is applied special adhesive, The length of tapeneeded is derived according to diameter and length of pipeline.
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电伴热产品附件 Accessories
九、 喉卡 Pipe clamp
喉卡由10mm宽1.0mm厚连续长度的不锈钢带以及固定螺丝所组成。它可以将接线盒等附件固定在管道上。钢带可根据管径大小,按实际需要长度剪切。安装时,调节固定螺丝,即能将接线盒或其它附件固定在管道上。订货时,须提供紧固螺丝套数和所需钢带总长。每圈钢带长度是固定钢管外周长的1.1倍。
This 10mm wide 1.0mm thickness pipe clamp is consist ofcontinuous steel strip and fix screw, It is used to fasten connectionbox and accessories by adjusting fix screw to pipe. It can be cutaccording to diameter of pipe. When you are ordering, pleaseindicate number of screws and length of strip, The length of a rollstrip is 1.1 times as long as perimeter of pipe.
电伴热产品附件 Accessories
十、 示警铭牌 Alarm nameplate
示警铭牌为200mm×120mm的不干胶铭牌,贴于施工完毕的伴热管线外表面作为示意及通电示警,一般每隔30m左右在易见位置贴一块。
This 120mm wide 200mm long alarm nameplate is used to attachto the outside of the pipe insulation at about 30m intervals.
电伴热产品附件 Accessories
十一、 船用附件 Marine accessories
船用附件包括船用电缆接线盒、 中间接线盒、终端接线盒和温度控制器;它是使用船用电热带的必备套件。船用电热带防爆附件的结构、工作与前述相应的防爆附件相同;其型号命名是在原防爆附件型号前派字母“C”(表示“船用”),如船用二通接线盒型号为“CZZH”(一般用二通型号为“ZZH”)
船用附件除有前述附件的全部特点外,还具有防腐性能好、防霉菌生长,滞燃和绝缘可靠等特点。船用附件通过船检的各项试验,其铭牌上角标有防爆标志:“EX”;左上角标有船检合格标志:“Z C”
Marine accessories include marine power box, splice connection kit, end termination kit and temperature controller. Itis similar to above Ex-proof accessories, Type named: the front of explosion-proof accessories add“C”,Such as: type ofship’s classification splice connection kit is“CZZH” (general type of splice connection kit is “ZZH”), Besides allfeature of above accessories, It has corrosive-proof, mould-resistance, flame-retardant and insulation reliable. It has passthrough various test, with Ex-proof mark: “Ex”and shipÕs classification qualified mark:“Z C” at the corner of nameplate.
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电伴热产品附件 Accessories
十二、 配电箱 Power panel
本配电箱专供本公司生产的各种电热带和挠性电热板配电用。配电箱有防爆和非防爆两类,具体根据客户要求进行选用。配电箱具有过载、短路和漏电保护功能。
With overload, short circuit and electricity leakage protection, the panel used for control heating cable, flexipanel, andcontrol equipment and supplying power, The panel has Ex-proof and no-Ex-proof two classify. The selection must be basedon customer requirement.
1、 型号含义 Type number nomenclature
XR -J
是否配接触器(否不注) contactor配电回路数(1-4) branch number电源配电箱 power panel
电路相线数(1:单相220V;3:三相380V circuit phase number)
前加Ex表示防爆,非防爆不注。
2、 分类、参数、结构和安装调试 Classify, specification, construcation and installation
XR系列电源配电箱分单相和三相两种形式。单相有1-4回路四种规格:三相有1-3路回路三种规格。当电伴热系统配用温控器,而温控器容量不够或电热带为三相时,配电箱可选用带接触器的。电源配电箱的安装非常简单,只需将两根挂铁按规定尺寸固定在墙上自由放置,就可将电源箱挂上。电源配电箱有关参数见表3-2。另外,我公司为用户提供非上述的各种控制功能的配电系统,从简单的温度控制、过载和短路保护到温度的程序控制、各种保护及报警直至通过计算机对伴热系统进行遥测、遥控。
XR series power panel has two range(single and three phase). Single phase has 1-4 branch, Three phase range has 1-3 branch, The door of power panel is sealing constrction, There is a circuit breaker with overload, short circuit, and electricityleakage protection on the ground plate, When you are using three phase heating cable or temperature-conrtoller capacityinsufficient. Please select power panel with a contactor, easy to install the power panel, please fix a iron stick on the wallaccording to the panel size, Then the panel is hung on it and set the switch“off”,Please connect the power source andload, set the switch “on”in order. Our company can provide a various power panel system.表3-2电源配电箱产品技术参数表 Technical data规格单相220V三相380V型号额定电流漏电动作电流1XR-J20,30A30mA3XR-J20,30A30mA注: 所谓的几回路就是由几个如表中所示的回路并联而成。
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安装 Installation
一、 安装总则 General installation guide
a. 本电伴热产品可用于工厂一区、二区防爆场合。安装时,应避开油气积聚的暗角等可能超过上述规定的防爆区。b. 电伴热产品具有全天候防护能力。但安装时应使系统不会发生积聚雨雪。在这前提下,应使系统维护方便及整齐和美观。
c. 所有电伴热防爆产品除防爆等级外,电热带尚有防爆温度组别,请注意产品的正确选用。电伴热产品在空气中的表面温度应受到有效的控制,不得超过危险介质自燃温度的80%。(详细见样本,防爆说明一章)
d. 电伴热产品的安装必须在管线系统全部安装、调试结束后进行。e. 施工前,应检查产品是否符合本说明中规定的各项技术指标。
f. 施工后,应先检查系统,其绝缘电阻不管其长度长短不小于20MΩ (用500VDC摇表)。系统是否有短路现象(长度较长的自限式电热带在冷态时,其阻值较小)。
测试A: 电热带母线与屏弊层之间
测试B: 屏弊层与金属管之间(针对加强型而言)500 VDC摇表g. 检查无误后,通以额定电压,逐段检查发热情况和各电气参数是否正常。
h. 电伴热系统送电运行正常后,可进行保温、防护层的施工。施工后,电伴热系统重复f、g条的检查并连续进行一昼夜。i. 本总则未将现行的“电气装置安装工程施工及验收规定”及“防爆、防火规程”中有关条文包括在内,施工中仍应遵循上述技术常用规范要求,在此不作复述。
a. The heating cable can be used in divsion 1,2 hazardous area and it is free from installation in the place that oil gashas been gathered. The power panel could be applied in non-hazardous areas or hazardous areas based on Panelapprovalled class.
b. The heating cable is weather-proof. But the system must be avoid gathering rain or snow possible.c. The heating cableÕs surface-temp in the air dosenÕt exceed 80% self-fire temperature of dangous fluid.d. The heating cable is installed after the pipeline installation has finished.e. Before installation, check and verify all specification according instruction.
f. After installation, Check system insulation resistance no less than 20MΩ with 500V megohmmeter and verify DCresistance of cable avoid shorting circuit.
g. Feed the power sources. Check heating of the cable and electrical specification.h. If the power sources is right. The thermal insulation cable can be insulated.
i. Electrical installation must be according to “electrical installation and test guide” and “Explosion-proof, fired-proofguide ”.
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安装 Installation
二、 电热带的安装 Installation of heating cable
安装电热带时应注意以下几点:
a. 施放电热带时不要打硬折或长距离在地面拖拉。
b. 安装电热带碰到锐利的边棱要先垫上铝胶带或将其锐利处打磨光滑,以防将电热带外层绝缘划破。c. 电热带最小弯曲半径应不小于其厚度的五倍。d. 电热带应紧贴管道表面,以利散热。
e. 安装电热带应采用铝胶带粘贴,一则增大散热面,有利于热传导;二则方便安装。其方法是: 先清除电热带途径处的油污、水份,最能用汽油揩清。首先每隔八十厘米,用固定胶带将电热带径向固定,然后敷设复盖铝胶带,最后将布用力抹压,使电热带平整粘贴在管道表面。
f. 安装电热带附件时,应将电热带留有一定富裕量,以便下次检修重复使用。
g. 安装恒功率率电热带时,由于恒功率电热带在整个长度上是一段段发热节组合而成,剪切时须特别注意电热带上发热区确保发热部分控制在需伴热的部分。见图4-13
h. 除自限式电热带外,其余型号电热带不允许叠绕、交叉、避免造成交叉处过热。i. 由于自限式电热带发热芯料系导电材料,在安装时电源的铜线应加套管,以免短路。j. 电热带配电系统应具有过载、短路、漏电保护。Caution:
a. Do not kink or crush the cable or pulling it overb. Aviod installing against sharp edges
c. Minimum bending redius no less than 5 time its thicknessd. The cable must be attached pipe surface firmly for heat sink
e. The heating cable installation will require the use of Aluminum tape as possible, Not ony increase heat sink. But alsoincrease heat transfer.
f. Leave extra cable at all accessories to facilitate easy working of the connectionsg. It is free from the cold section during installation of the cable (see figure 4-13)h. Besides self-limiting heating cable, The other heating cable allow not to overlap.
i. The self-limiting heating core exturded the bus wires is electrically conductive and Should be treates as a conductor.j. It must be applying a device with overload. short-circuit. Electric leakage and Temp-control protection in the heatingsystem.
管道 pipe固定胶带 glass tape电热带heating cable保温层thermal insulation保温层thermal insulation管道pipe电热带heating cablea.普通使用场合,可用胶带把电热带紧固,然后再加复保温层a. ordinary area, Fasten the heating cable tothe pipe with tape, then cover insulation铝胶带 aluminum tapeb.用50毫米宽铝胶带能加强传导,提高发热效率b. With 50mm wide aluminumtape to increase heat transter电热带管道heating cablepipe防水层watertight jacket电热带heating cable80 公分左右固定胶带glass tape图4-1 电热带缠绕管道示意图
schemeatic diagram
图4-2 电热带安装位置
cable postition
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安装 Installation
图 4-3 电热带螺旋缠绕管道heating cable on pipe
2倍的管托长度2 time length of shoe
管道 pipe
管托
电热带heating cable
support shoe
固定胶带glass tape
电热带heating cable
阀门valve
管道pipe管道pipe电热带heating cable
阀门valve
固定胶带glass tape
固定胶带glass tape
图 4-4 电热带过管托架
pipe support
电热带heating cable
管道 pipe
固定胶带glass tape
图 4-5 电热带缠绕阀门heating cable apply to valve
泵出口
pump discharge
固定胶带glass tape
泵进口pump section
马达motor
泵出口
pump discharge
泵体pump
固定胶带
管道 pipe
glass tape
图 4-6 电热带缠绕三叉管
pipe tee
固定胶带glass tape
电热带heating cable
液位表level gauge
图 4-7 电热带缠绕泵体
heating cable apply to pump
截面图cross section
防水外壳weatherproofing
保温层
thermal insulation
容器壁tank wall
电热带heating cable
电热带heating cable
水位表level gauge
图 4-8 电热带缠绕水位器heating cable level switch
电热带heating cable
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安装 Installation
固定胶带
防水层 watertight jacket保温层 thermal insulation固定胶带 glass tape
尾端 end seal
电热带 heating cable
地面 grade
管道pipe
电热带heating cable
防水栏 rain shield
glass tape
冻土层 frost line封口 seal thoroughly
图4-9 电热带缠绕埋地管heating cable underearth pipeline
图4-10 电热带缠绕法兰heating cable apply to flange
固定胶带glass tape
管道 pipe
过滤器 strainer
固定胶带glass tape
电热带heating cable
电热带heating cable
图4-11 电热带缠绕压力表heating cable apply to indicator
图4-12 电热带缠绕过滤器Typical Strainer Installation
尾端End Seal
电源接线盒
Power Connection Kit
节点Node
固定胶带
Fiberglass tape
保温
Insulation
中间接线盒In-line splice
电热带环绕
Heater cable loop
钢带
Pipe Clamps
节点Node
T接线盒Tee splice
图 4-13 恒功率电热带在管道上的典型安装
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三、故障检修 Troubleshooting
故障迹象Symptoms
可能成因Probable Cause
校正方法Correction
A) 线路断路器跳闸
Branch Circuit Breaker Trips
1 断路器选型太小
2 线路需电量超过断路器容量3 线路在低于设计起动温度下起动(针对自控温电缆)4 断路器故障
5 接线盒或其它配件有短路6 伴热线受到机械损坏7 尾端处误将伴热两导线连接
1,2,3) 重新计算核对线路所需电
量再选配合适的断路器(注意供电电缆的载流量是否合适) 4) 对断路器进行检修 5,6)确定故障所在,进行重装
或更换,并用摇表测试,判明短路方法如下: a)视察所有接线配件安装
完整无缺
b)视察管道配件是否有维修
过并对伴热线造成损坏 c) 视察保温层是否有损坏或
压伤的地方,如还不能找出故障就需将线路每一段伴热线隔离,再分别用摇表测试故障所在
B) 线路断路器因漏电开关而跳闸Ground fault breaker trips
1) 参考(A)校正方法
2) 接线盒或配件累积过多潮气3) 电热带或供电电缆有裂痕并有潮气存在
1) 参考(A)故障迹象
2) 将故障处吹干后重装,再用摇表测试3) 将有故障段更换
C) 系统发热量为零或偏低
Power output is zero or less thanrated
1)供电电压趋零或偏低
2)中间接线盒内电热带没有被连
接上或电热带被切断3) 接线盒中电热带没有拧紧4) 温控器错误调在正常关闭的状态5) 管道处于高温状态
6) 电热带曝露于高潮气里或高温下
而损坏
1) 对供电系统进行检修2) 检修配件和电热带的长度,重新计算线路应有发热量3) 收紧各连接点螺钉4) 重调至正常长开的位置5) 检查电热带是否损坏,管道温度是否与设计温度相符6) 伴热线应加以更换
D) 系统发热量正常但管道温度低于
设计数值
Power output appears correct butpipe temp are below design value
1)保温层受了潮湿
2)在散热体上没有足够的电热带3)温控器调正不正常
4)在进行热损失计算时所用的参
数有前后不一致
1) 将受潮湿的保温层更换上干燥的,并加上防水罩
2) 用二通补上所缺电热带,但总线路长度不可超过极限3) 重新调校温控器
4) 重新核对设计参数并做必要的调整
注: 计算发热量方法如下:1) 测量在有保温层下的管道温度
2) 线路供电后最少10分钟再测量电流(Ix)
3) 伴热线发热量W/m是电流(lx)乘电压再除以线路总长度
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安装 Installation
四、 挠性电热板的安装 Flexipanel installation1、 挠性电热板的安装位置 installation location铝胶带卧式罐 horizonal vessel
坚式罐 vertical vessel挠性电热板安装一般如图所示: 尽可能挠性电热板安装在正常工作时的最低液位下方。如果最低液位不明显或容器经常空着,则将挠性电热板安装在容器高度的1/3以下部位。
Position Flexipanel as showm in type 1 or 2. Flexipanel shoud be positioned below the minimun liquid level expectedduring normal conditions as possible, If the minimum liquid level is not known or if the vessel is emptied. place flexipanel onthe lower1/3 of the vessel.
2、 涂粘合剂和贴发热板 Apply adhesive to panel
临贴板前,将罐体粘贴表面处理干净,随板附件A、B两支粘合剂全部挤在挠性板粘贴面上,充分搅拌均匀,并涂覆刮平,不得有漏涂处。接着,迅速将涂有粘合剂挠性板的中部贴容器表面,然后由中心向四周逐渐贴平,并用手压紧,赶出空气,再按图所示,用铝胶带固定。涂贴挠性板的整个操作时间须短于1小时,以免粘合剂过早固化。粘合剂固化时间: 温度20℃时: 12-48小时,如果温度降低则固化时间延长; 如需缩短时间,可通电加热(如75℃时约15分钟就可固化)。
Before installaion. It is recommended that wall surface be reasonably clean in the where flexipanel is to be installedplease mix A adhesive with B. then apply mixed adhesive to back side of flexipanel to from the center to arround. tapecircumferentially around flexipanel with aluminium tape. The time does not exceed 1 hour during lacquer flexipanel in caseadhesive is solidfied, The time of adhesive solidify: 12-48 hour at 20℃.
3、 覆盖保温层 Coating insulation
用耐温隔热材料(如硅酸钙、玻璃纤维、石棉制品等)覆盖在挠性电热板及罐体外表上,以使容器保温。耐温低于150℃的材料不准覆盖在挠性板上。
Insulate vessel with high-temperature insulating material such as silicate, fiberglass, celluar glass mineral wool, Insulationrated below 150℃ should not be used over Flexipanel.
4、 装配用附件 Accessories
购买本产品,随货提供如下附件: enclose accessories
粘结剂两瓶(A组及B组各一),刮刀一把、手刷一把、铝胶带一圈。以上附件和一块挠性电热板组成一个包装。A,B part heat adhesive a brush and a scraper, a roll aluminum tape package include above accessories and aflexipanel.
5、 注意事项 Caution
本产品接线盒有接地螺栓,安装时请可靠接地。罐体表现的金属外壳必须严格保持良好接地。It is important for connection box and surface of vessel to ground reliability.
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产品造型设计及计算方法 Design and selection
电伴热是利用电伴热产品的产生的热量来补偿被伴热的管道、容器、罐体等工艺装置所散耗的热量,以维持其相应的介质温度来满足工艺要求。正确计算出管道、容器、罐体等工艺装置的散热量,对准确维持介质温度是至关重要的。
An electric heating cable system uses the heating cable to replace the heat that is lost throuth the thermal insulationsystem. Replacing the lost heat allows the pipe and product inside the pipe to be heat at a constant temperature. It isimportant for selecting heating cable to calculate the lost heat on the pipe. Vessel and tank.
一、 管道及附件散热量的计算 Calculate the heat loss of pipe and accessories1、 工艺参数的确定 Determination of parameters
为确保计算的正确性,在计算前应正确确定各项参数: 它们是管道、容器、罐体等介质要求维持的温度T。管道的直径d或容器的表面积S、保温材料的品种及厚度δ、环境温度(最低平均温度)TH、敷设环境(室内或室外、地面或埋地)。并计算维持温度TW与环境温度TH之差△T,△T=TW-TH
It is desired pipe, vessel maintenance temperature (TW) and minimum ambient temperature (TH) and pipe diameter(d). surface areas of vessel(s), thermal insulation type and thickness.
2、 管道散热量的计算 Thermal design
Q=f×e×h×q
Q-实际需要的伴热量 heat loss
q-基准情况下单位长度管道的散热量 q(根据工艺参数查表5-1得到) basic heat lossf-保温材料系数(查表5-2) thermal insulation factor (see chart 5-2)
e- 管材系数 (金属为1,非金属为0.6-0.9) pipe factor (metal 1,no metal 0.6-0.9)h-环境系数 (室外为1,室内为0.9) ambient factor (outdoor:1,indoor:0.9)
例1: 某厂有一金属管线,管径为1/2”,保温材料是硅酸钙,厚度10mm,管道中介质的维持温度10℃,冬季最低平均气温是-25℃,室外。求管道每米热损失。
Example: There is a pipeline to be maintained at 10℃, Min ambient temperature is -25℃, pipe diameter is 1/2”(inch), Insulation is 10mm thickness calcium silicate in outdoor.
一: △T=TW-TH=10℃-(-25℃)=35℃
二: 查表5-1,管径1/2”,10mm保温层,因表中无△T=35℃需采用插入法计算;
use table 5-1 pipe diameter 1/2”,10mm thickness insulation where desired temperature differential falls between values,use interpolation:
△T1=30℃时,q1=11.0W/m;△T2=40℃时,q2=14.9W/m;
△T=35℃时,q=q1+(q2-q1)/(△T2-△T1)×(△T-△T1)=11.0+(14.9-11.0)/(40-30)×5=12.95W/m;
三: 保温层采用硅酸钙,查“表5-2” From table 5-2 (calcium silicate)f=1.5 e=1 h=1
四: 所需伴热量 Require heat: Q=1.5×1×1×12.95=19.425(w/m)
注意: 表5-1中保温材料是采用玻璃纤维为标准的,如用其它材料可参见表5-2的系数进行修正,如前面例1所述。
Note: Insulation correction factor are bassed on glass fiber insulation
自限式电热带应选用维持温度下的功率大于等于所需伴热量的型号。(见图2-2、2-3)
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表5-1管道散热量(QB)
散热量QB,以瓦特/米(W/m)单位表示表1中的散热量计算基于几个基本参数保温材料:玻璃纤维
管道材料:金属
管道位置:室外、风速8.9米/秒
室内=室外×0.9
保温厚度(mm)
温差△T管道大小(℃)
NB(mm)NPS(寸)外径(mm)203040
81/4146.29.412.74.06.28.312.83.65.47.411.415.620.13.35.06.710.314.218.322.727.232.137.12.84.35.89.012.315.919.723.727.932.32.63.95.38.111.214.417.821.525.329.22.13.24.46.79.211.914.717.720.924.1
151/2217.211.014.94.67.09.514.74.16.28.412.917.722.83.75.67.611.716.020.725.630.836.242.03.14.86.510.113.817.822.126.531.236.22.84.35.99.012.416.019.823.828.132.52.33.54.87.410.113.016.119.422.926.5
203/4278.512.917.55.38.110.916.94.67.19.514.720.226.14.26.38.613.218.223.429.034.941.147.63.65.47.311.315.520.024.829.835.140.63.24.86.510.113.817.822.126.631.336.22.63.95.28.111.114.317.821.425.129.1
2513410.115.420.86.29.412.719.65.38.111.017.023.330.14.87.39.815.120.826.833.240.047.154.54.06.18.312.817.622.728.133.839.846.03.65.47.311.315.520.124.829.935.240.72.84.35.89.012.315.919.723.627.832.2
3211/44212.118.525.07.311.115.023.16.29.512.919.827.235.15.58.411.417.624.131.138.646.454.663.24.67.09.514.720.226.032.238.845.652.94.16.28.412.917.722.828.334.040.146.43.24.86.510.013.817.822.026.531.236.1
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5026016.424.933.79.514.519.630.28.112.316.625.635.145.47.110.814.622.530.939.849.359.469.980.95.88.912.018.525.432.840.648.857.466.55.07.710.416.022.028.435.142.349.857.63.85.87.912.116.621.526.632.037.743.7
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2020304060
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302030406080100120140160180
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8038923.035.047.313.019.826.741.210.916.622.434.547.461.29.514.419.530.041.253.265.979.393.3108.17.611.615.724.333.343.053.364.175.487.36.59.913.420.728.536.745.554.764.474.64.87.39.915.320.927.033.540.347.454.9
100411428.843.859.216.024.433.050.913.420.327.542.458.275.211.617.623.836.650.365.080.496.8113.6131.99.214.119.029.340.252.064.477.491.1105.57.811.916.124.834.144.054.565.677.289.45.78.611.617.924.631.839.947.355.764.5
150616841.162.584.522.534.246.371.418.628.338.259.081.0104.515.924.332.850.669.489.7111.0133.5157.2182.012.619.125.939.954.870.887.6105.4124.1143.710.516.021.733.445.959.273.388.2103.9120.37.411.315.223.532.241.651.561.972.984.4
200821952.680.0108.228.543.458.790.523.535.748.374.5102.3132.020.130.541.363.687.3112.8139.6168.0197.7228.915.723.932.349.868.488.3109.3131.5154.8179.313.119.926.941.456.873.490.9109.3128.7149.09.013.718.528.639.250.662.775.488.8102.8
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3001232476.1115.8156.640.962.384.2129.933.551.069.0106.3146.0188.528.543.358.690.4124.0160.2198.3238.6280.8325.222.133.645.570.196.2124.2153.9185.1217.9252.218.227.737.557.879.3105.4126.8152.5179.5207.912.318.725.339.053.569.185.5102.9121.1140.3
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产品造型设计及计算方法 Design and selection
表5-2: 保温材料修正系数 insulation correction factor
3、 管道阀体散热量的计算 Heat loss of valve
闸阀散热量通常是相连口径管道每米热损失的1.22倍:
The heat loss of gate valve is 1.22 times that of pipe(the same diameter)球阀为0.7倍 ball valve 0.7 factor
蝶型阀(节流阀)为0.5倍 butterfly 0.5 factor浮式球阀为0.6倍 inlet valve 0.6 factor
4、 确定电热带的功率及长度 The heating cables power and length selection:
根据散热量及介质维持温度选择相应的电热带,其最高维持温度必须高于介质温度,单位长度大于电热带额定功率时(即比值大于1时),用以下方法来修正:
a. 当比值大于1.5 时,采用两条或更多的平行电热带敷设,电热带长度为管道长度×根数
b. 当比值在1.1-1.5之间时,可采用卷绕法,如图5-1,方法为根据热损失与电热带功率的比值。查表5-3,得到卷绕的节距,并按此敷设,电热带长度为管道长度×比值。
c. 修改保温材料或厚度。
According to heat lose of the pipe and select a proper heating cable. The maximum maintenance temperature must behigher than fluid temperature, If heating cable rated power exceed heat loss of pipe. The following are procedures to solvethe problems:
a. The ratio between heating cable and heat loss of pipe exceed 1.5, It is required that two heating cable to be attachedon the pipe.
b. The ratio falls between 1.1 and 1.5, The heating cable may be spiral wrapped to incresase the total wattage of thetracing system. Installed cable length=pipe length×spiral factor (see table 5-3)
c. Change thermal insulation material or increase it’s thickness.
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图 5-1
产品造型设计及计算方法 Design and selection
另外还应考虑法兰、弯头及和管道金属托架散热损失所需的电热带长度及预留供电源接线用的长度,预留供中间接线盒接线用的长度。法兰一般加上2倍的管径长度;弯头加上1.5倍的管径长度;管道金属托架上加3-5倍的管径长度,伴热管所需的电热带长度,其总和即整个系统所需电热带的总长度。
Additional considering of adding the amount of heating cable install on each valve, flange, pipe support, power connectionand splice connecton, Adders are for(flange is 2 times pipe size, elbow is 1.5 times and pipe support is 3-5 times, Powerconnection adds 1 meter and splice connection add 0.5 meter),Total heating cable requirement is add up length of accessoriesand cable length.
表5-3: 电热带跨距 (pitch in mm)
二、 罐体容器散热量的计算 Heat loss of vessel
首先应计算容器罐体的表面积,并根据保温层材料、厚度和介质所维持的温度,查表5-4,可知每平方米的散热量,再通过计算,就能得到容器、罐体所需的总散热量Q。
The first determaination is the total surface area A of the vessel, The heat loss in table 5-4 are based on insulationmaterial thickness and fluid temperature. The formula is:
其公式为: Q=1.2×q×s式中: 1.2为保险系数(safe factor)
q: 为每平方米散热量 (W/m2)(heat loss in a square meter)s: 为容器罐体的表面积 (m2)(surface area of vessel)
例2: 某厂有一直径D=3m,高h=4m的圆柱形工艺罐体,当地最低环境温度-10℃;最高风速15m/S,现采用厚度50mm的矿渣棉作保温层,罐体的维持温度80℃,求该罐体散热量。
Example: There is a 3 meter diameter, 4 meter high vessel, minimum ambient temperature: -10℃ Max wind speed:15m/s, thermal insulation is 50mm, Slag wool, maintenance temperature is 80℃.
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产品选型设计及计算方法 Design and selection
二、罐体容器散热量 q(w/m2)Heat loss of vessel
保温材料厚度(mm)3850维522.3117.2511.718.867.145.9635.9128.0719.2714.6411.869.921025.0819.3913.169.968.026.7040.1531.3921.5416.4313.2611.092030.7923.8116.1612.239.858.2348.7938.1426.1819.9716.1213.533036.7728.4319.3014.6111.769.8457.7745.0830.9523.6019.0515.994043.0233.2722.5817.0913.7711.5266.8952.2035.9027.3322.0618.525049.5538.3226.0219.6915.8613.2776.3959.6240.9331.1625.1621.12持6056.3843.6129.6122.4118.0515.1086.0267.1446.1035.0928.3823.79温7063.5249.1433.3725.2920.3417.0295.9277.8751.4139.1731.6626.53度8070.9854.1937.2928.2522.7319.02106.0882.8156.8743.3735.0229.35℃9078.7760.9541.3931.3625.3621.11116.6391.0662.4947.6538.4832.2510086.9167.2045.6834.6027.8523.30127.3899.4668.3152.0542.0335.23120104.1880.6354.8241.5133.4327.97149.77116.9780.3661.2449.4541.45条件聚氨酯751001251503850温度-40℃玻璃纤维75100125150最385044.1434.6523.9918.3414.8312.5152.6241.6328.9522.2618.0215.167.876.044.143.122.512.1349.3238.7226.8120.4916.5713.9759.0046.6932.4724.9720.2217.0010.618.225.584.213.432.8759.9547.1632.5324.8620.1816.9672.3857.0739.7730.5324.7220.8716.3012.628.586.525.274.4170.8355.6338.4429.3823.8020.0085.9667.9247.3436.2829.4324.8022.5317.3011.808.917.206.0281.8164.2544.4934.0127.5023.1199.9579.0155.0842.2134.3128.8628.6122.1615.0611.459.227.7193.1973.1950.5938.6731.2726.28114.5990.5963.0648.3439.2933.0535.1727.2418.5514.0711.349.48104.6182.1756.8143.4335.1229.51129.45102.3771.2854.7444.4237.3742.0432.5622.1816.8313.5611.33116.3691.3263.1448.2739.1132.81144.73114.4979.7461.2449.7041.8149.2338.1325.9719.7115.8813.27128.34100.7469.5963.2143.1136.17160.56126.9488.4467.9355.1346.3956.8344.0329.9422.7218.3115.30140.42110.2376.2358.2447.1539.62176.68139.7297.3874.8160.7251.0864.7050.1334.1025.8720.8517.45152.71120.0182.9363.4151.3443.11193.21152.84106.5581.8766.4555.9272.8656.4638.4429.1723.4719.67178.08139.8696.7673.9359.8650.26矿渣棉751001251503850风速15m/s低227.48180.06125.6196.5478.3865.9690.3170.0647.7136.2029.1424.40硅酸钙751001251503850环聚氨酯751001251503812.139.536.585.064.073.4015.0111.658.216.235.104.2716.4212.798.836.795.464.5720.1215.8811.18.356.845.7225.1619.6113.5310.328.377.0030.5124.0716.6912.7710.378.6834.0026.6118.2913.9511.319.4641.2732.5722.4916.9313.9711.7943.2533.7223.2617.6814.3411.9952.3341.1428.5221.8217.6514.8952.6141.1828.3121.6017.4514.6563.5749.9734.5826.4621.4818.0662.2448.7233.4925.5620.6417.3475.0559.0140.8431.2425.3821.2972.2756.4738.8329.6323.9320.1086.6368.1247.1536.0729.2424.5882.4764.4544.3133.8227.3222.9498.4177.3953.6841.0733.2227.9392.9572.6550.0538.1230.8025.86110.1287.0060.2346.0937.2931.35103.7281.1555.8642.5634.3828.87122.8496.6366.9151.2041.4234.82126.3198.8568.0051.8141.8935.15148.06116.4980.6161.6949.9642.00温度-10℃境玻璃纤维507510012515038矿渣棉5075100125150风速15m/s温3818.1314.3810.027.756.255.3324.3919.3513.4910.438.427.1737.3929.6620.7615.9212.9510.9450.9040.3928.1621.6917.5814.855.474.353.042.291.841.548.236.374.483.512.832.3764.8251.3435.9527.5822.4418.8811.619.086.234.783.903.2616.7113.169.267.135.744.8879.2162.7543.8633.7227.3823.0517.8713.979.597.366.005.0125.4520.0514.1010.868.887.4393.8874.5452.0240.0032.4827.3924.4419.1113.2210.068.206.8534.4527.3719.0814.6912.0210.05109.1886.5460.5246.5437.8031.8231.3324.5016.9412.8910.518.7843.7334.7424.4118.6515.2512.76124.7198.8769.1753.1943.2136.3738.5730.2720.8515.9812.8410.8153.3042.3329.7522.9018.5815.66140.78111.6478.0560.0448.7641.0546.1536.2224.9519.0515.4112.9363.4150.1635.2427.1322.0118.56157.28124.2887.1767.0654.4845.8654.1042.4629.2422.3218.0615.1573.6158.4540.9031.3725.5421.53191.24151.79106.1281.6666.3555.8671.1255.8138.4329.3423.7319.9094.9575.4052.5640.4532.9327.67硅酸钙507510012515038聚氨酯507510012515038度玻璃纤维5075100125150温度+20℃389.667.785.324.323.482.9211.089.526.835.204.353.7719.9315.7311.128.597.045.8924.0219.4913.8910.958.997.6729.8823.8516.8613.0210.679.0837.3230.0021.5516.7013.7211.7040.6132.4222.9117.6914.3712.2350.5741.0129.2122.8318.5915.8551.2940.9428.9322.3318.2915.4464.2252.0937.1128.9923.8120.1362.1749.6235.0727.0722.1718.7278.2863.4945.4235.3529.0224.5473.2658.7241.3232.0326.1322.0692.7375.2253.8141.8834.3829.0884.9167.7747.8936.9730.1625.46108.0487.2862.4448.6039.9033.74108.2186.3761.0347.1138.4332.44139.02112.3580.4062.5851.3743.44矿渣棉507510012515038无风速硅酸钙507510012515052
产品选型设计及计算方法 Design and selection
一: 查表5-4知: 在风速15m/S,环境-10℃,维持温度80℃时,q=77.39W/m2The heat loss in the table is : q=77.39W/m2二:
Q=1.2×q×s=1.2×q×(2πR2+πDh)
=1.2×77.39×(2×3.14×1.52+3.14×3×4)=4811.49(W)答: 该罐体散热量为4811.49W
如实际情况与表中不一样,请采用插入法计算。
If value falls between two values, please use interpolation.
三、 有关公式介绍 Formula
如前所述,我们查知的管道,容器罐体的散热量,是按现场实际情况综合计算得知的,如数据表中没有您所需要的散热量,则可通过有热损失公式来求出所需要的数据。有关公式简介如下:
The above table is derived by the actual situation, It is also calcuated by following formula:a. 管道热损失公式为 heat loss of pipe:
2πλ(TW-TH)In[(d+2δ)÷d]
b. 板面热损失公式 heat loss of panel surface:
πλ(TW-TH)δ/λ
Q=(W/m)
Q=
×S (W)
上式中:
λ-保温材料是导热系数(W/米/度) thermal conductivity of insulationd-管道外径 (mm) pipe outer diameterδ -保温层厚度 (m) insulation thickness
TW-工作维持温度 (℃) maintenance temperature
TH-当地最低平均温度 (℃) minimum average ambient temperatureS-表面积 (m2) surface areaQ-散热量 (W) heat loss
以上公式系理想状态,实际工程计算时应综合考虑风速、保温层老化和保险系数等因数。
The formula is ideal sitiation, It must be consider wind speed, insulating ageing and safe factor in the application.
四、 选型方法 Selection of heating cable
在选择电伴热产品时,应综合考虑各种因素,如适用性、经济性、供电条件等,具体方法如下:a. 根据管道维持温度及偶然性的最高操作温度选定最高维持温度高于它的电伴热产品。
b. 根据供电条件、电网负荷及管道长度,确定电伴热方案和电伴热产品的型号,如恒功率、自限式或串联型等。c. 根据管道单位长度的散热量或容器单位面积上的散热量来确定所需电伴热产品的单位功率和长度。
d. 根据不同的使用环境来确定所需电伴热产品的结构: 一般情况下,可选用普通型,防爆场合建议使用加强型,埋地或在有腐蚀性物质场所应选用加强型。
To select the proper heating cable, consider the following:
a. pipe maintenance temperature and maximum exposure temperature.b. supply volatge, electricity net and length of the heating cable.c. The length of cable is derived by heat loss of pipe per meter.
d. The heating cable construction is based on surroundings (ordinary range in non-hazardous areas, Strengthenrange in hazardous areas)
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产品选型设计及计算方法 Design and selection
例3:根据前述“例1”所述,并最后得知需耗散的热功耗为19.43W/m,来进行选型。
根据选型方法步骤“1-4”,我们可初步选RDP2-J3-20型的电热带。若例(1)因管径增大,其它条件不变,散热量为30W/m时,则又根据步骤“1-4”,初步选择RDP2-J3-30型或RDP3-J3-30型的电热带作为伴热产品: 若为强腐蚀性环境,则可选加强型RDP3(Q)-J3-30型的电热带作为伴热产品。
例4: 根据例(2)所述,知容器表面积为52m2,最后求得散热量为4811.5W,根据步骤“1-4”初步选择LDB-B型挠性电热板为伴热产品,需电热板数量: n=4811W÷1200≈4(块)
注: 以上选择并不是唯一方法,在选择电伴热产品应以“最佳分布、低功率”为原则,并灵活应用。
五、 特殊情况的设计与计算 Design and calcuation in special condition
管线蒸汽扫线温度大于电热带耐热温度时的电伴热设计:
maximum explosure temperature higher than cable withstand temperature:
由于蒸汽扫线时间相应较短,可采用图5-2双层保温层结构来保证使用。一般来说,这种结构的内层保温厚度为5-10mm,在内保温层外包铁皮、铝皮或铝胶带,铝胶带上敷设电热带。每毫米内层保温层可使扫线温度降低10℃左右。当然在扫线时,电热带应停止通电。管线热损失仍按常规设计。保温层厚度只能按外层为计算厚度。例: 电热带材料F46氟塑料耐温为205℃,而扫线温度达250℃,那么内层保温层需敷设5mm以上。以确保扫线中不致损坏电热带。
Due to it short time for steam pass through the pipe, It may be select double layer thermal insulation, The inner thermalinsulation thickness is 5-10mm, Then aluminium tape and should be attached on the insulation, The heating cable is attachedon the aluminium tape, It decrease temperature of cable surface.
管道 Pipe内保温层 Inner insulation电热带 Tracer外保温层 Outer insulation金属薄膜(铝泊) Metal foil (aluminum)
温度 Temp最高管内温度 Max pipe temp内外保温界面温度Interface外保温表面温度Outer insulation face环境温度Ambient图 5-2半径 Radius54电热带在防爆环境中的设计和表面温度的计算
Design of Tracer in harzdous and calculate of surface temp of tracer
NEC 标准和 IEC标准对防爆环境的区分有着明显的差异,我国是参考IEC标准进行分类的。电热带在防爆环境中的设计和应用根据不同标准也有着差异。这一点我们在选型和设计方面必须值得注意。
根据最新的工业用电伴热测试、设计、安装和维护的IEEE515-1997标准第61条,电热带在防爆环境中的设计,我们必须注意几点:
1、 0区(IEC标准),电热带不允许使用。
2、 1区(IEC标准),所有的电热带和附件必须符合相应区域的温度等级和防爆要求。3、 在1区场合,有可能的话,控制和接线盒放在1区之外。4、 每个电热带回路,都需有独立的断路器进行控制。
5、 在1区场合,断路器必须带漏电保护功能,配电盘如在1区之内,也必须符合1区等级的防爆要求。
温度等级表:
电热带表面温度的计算
电热带的表面温度可按下列公式进行计算:T表面 =(WC)/(UA)+T维持
这里: T表面电热带的表面温度C
W: 电热带的输出功率(瓦/米)C: 系数1
U: 总的导热系数(W/m2.℃)A: 单位长度上电热带表面积(m2)T维持: 为管道的维持温度(℃)
总的导热系数U根据不同的电热带的结构是不同的,它是考虑传导,对流和辐射的综合系数。就我们单相恒功率而言:U=Pt(0.01665PS+0.06649)+9.596+0.08534PS这里: Pt为管道维持温度(℃)PS为管道通径(英寸)
通常情况下,电热带的表面温度可按以上公式计算。
但在IEEE标准中,特别在爆炸性气体1区场合(除非采用高温限温控制器),要求在最恶劣的环境下进行计算,例如考虑为温控器失灵时,电热带在最高环境温度下长时间的运行,工作电压考虑为偏差最大的情况按120%设计。电热带表面温度不能超过可燃气体温度的80%。
55
附录一、用户对电伴热常见问题的答复Frequent queries and answer
1、 为什么恒功率电热带米功率越高反而最高维持温度越低?
发热丝的温度(在0℃维持温度下)+外界维持温度必须小于绝缘材料的耐温等级。在相同维持温度下(例如在0℃温度下),米功率越高,发热丝温度也越高。因此当绝缘材料的耐温等级一定时,恒功率电热带来米功率越高,允许的最高维持温度越低。
2、 温度控制器如何接线?
BJW51型温控器类似我们常用的拉线开关,当电流在15A以下,此温控器可直接串联在电路中,当电流在15A以上,主电路必须通过接触器进行控制。
3、 恒功率电热带和自控温电热带经常提到最大电路长度,这是什么意思?
对于恒功率电热带由于随着长度的增加,电缆尾端的压降也将增加,根据IEC标准,电缆尾功率降不得超过输入端的20%,因此此时的电缆长度就规定为恒功率电热带的最大长度。自控温电热带的最大长度是基于某一规格的断路器的大小再考虑一定的冲击电流而定的。
4、 有人说自控温电热带比恒功率电热带节能,是不是正确?
并不完全正确。系统的节能与温控器有着密切关系。
5、 如果用自控温电热带来解冻的话,那么解冻时间如何计算?
因为自控温电热带随着温度的升高,输出功率降低,对外散热量由于管道温度的不同也在不断变化,因此计算比较复杂。但我们有专门的软件可以帮助用户解决类似问题。
6、 自控温电热带能是否需要温度控制器?
可以不要。但温控器可提高能效,在温暖的季节可以节省不必要的能耗。
7、 自控温电热带能否用于融雪场合?
不能,自控温电热带一般用于管线(或容器)的防冻和保温。对于需融雪的场合。我们有专门的融雪电热带。
8、 对于MI电缆,能否在工地现场进行焊接?
由于MI电缆的焊接工艺很复杂,另外焊接后还需要一定的水平测试手段。这些工作在现场很难完成。因此目前我们都是根据图纸或现场测量后在工厂预制。
9、 恒功率电热带安装时不可重叠,为什么自控温电热带可以?
由于恒功率电热带单位长度功率一定,如果重叠,会产生过热现象甚至烧坏电热带,而自控温电热带由于其自控温特性,即使重叠也不会产生过热现象。
56
附录二、电伴热咨询表Information Sheet
日期 Date用户 Client地址 Address 工程名 Project Name 电话/传真 Tel / Fax 电子信箱 Email一、管道电伴热设计 Pipe Heat Tracing Design
管径Pipe size管材Pipe type保温材料Thermal insulation维持温度允许最高过程温度Max allowable-temp介质Fluid防护等级Protect class阀门 数量NoValve 保温材料insulated法兰数量No of flange支架数量No of support 保温Insulated其他散热器型号Other Heat Sinks场合Location普通场合Ordinary腐蚀性Corrosive最大湿度Humidity可供电压Volts备注: 户内Indoor 强Highly 户外Outdoor 级 区 组 中等Mildly 风速Wind Velocity 防爆场合Hazloc 阀门名称Type 保温厚度Insu-thick 过滤器数量No of strainer 不保温uninsulated 数量Qty 保温厚度 Thermal insulation thick 环境温度 最高Max 最低Min 管长Pipe lengthTemp to be maintained Ambeint-temp 允许最低过程温度 Min allowable-temp二、罐的伴热设计 Tank Heat Tracing Design
容器Tank 垂直Vertical容器类型Type 平板Flat容器高度High保温材料Thermal Insulation容器支架Support容器材料Tank material伴热温度Temp to maintained位置Location 户内Indoor腐蚀性Corrosive 强Highly最大湿度Humidity可供电压Volts备注: 水平Horizonal 圆柱Conical 宽度Wide 直径Diameter 保温厚度Thermal thick 坐地Ground 铁架支撑Pad 容器厚度Tank wall thick 最低环境温度Min Ambient-temp 户外Outdoor 区 组 中等Mildly 最大风速Wind Velocity普通场合Ordinary 防爆场合Hazloc 级57
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