Application Of Heat Shrinkable Materials In Motor

- Nov 21, 2018-

Thermal shrinkable materials are divided into heat shrinkable tubes and heat shrinkable tapes according to the shape of the supply. According to different uses and applications in different parts of the motor, the application of thermal shrinkable materials in the motor is explained.

Application of a heat shrinkable tube on motor

L, lead wiring identification system

Because of its good electrical performance, copper stability, solvent resistance and corrosion resistance of impregnating paint, the heat shrinkable sleeve can also be marked with marking letters according to the requirements of motor design, so the heat shrinkable marking tube can be used to replace the traditional metal aluminium sheet which is easy to fall off and break when designing the lead wire of motor stator and its winding accessories. Wiring identification system.

The shrinkage rate of heat shrinkable pipes, the uniform identification of all series of motors, and the striking and beautiful identification should be taken into account when using heat shrinkable pipes as lead marks in the design of lead wires. The radial dimensions of heat shrinkable pipes, the printed letters and their colours, and the colours of heat shrinkable pipes should be specified in detail.

2. Special motors are insulated and sealed.

The temperature rise of H-class motor cable is high, and the quality of silicone rubber cable is unstable sometimes. The insulation of H-class motor stator cable is protected by heat shrinkable tube, which can improve the reliability of the motor.

Thermal shrinkage pipe has corrosion resistance (158 C, 7 days), and the three-proof coating on the end of coil can not be applied on the lead-out wire, so when TH treatment motor stator lead-out wire is designed, the insulating part of TH treatment motor stator lead-out wire is covered with thermal shrinkage pipe insulation protection, which can play the role of sealing, moisture-proof, salt fog-proof and mildew-proof. .

3. Heat shrinkable tube heat shrinkable process

Regardless of whether the heat shrinkable pipe is used as the lead sign or the special motor lead wire as the insulation and sealing protection material, only the heat shrinkable process is scientific and reasonable, which can ensure the heat shrinkable pipe reliable, practical and stable. The following is the heat shrinkable process and points for attention.

1) Radial dimension design and thermal shrinkage bursting: the shrinkage of the heat shrinkable tube is more than 50% along the radial direction after heating. In order to ensure that the heat shrinkable tube is firmly fixed on the carrier, its radial dimension must be selected appropriately. The radial dimension is too large to be fixed firmly after heat shrinkage, and the radial dimension is too small to cause explosion when heat shrinkage and motor baking.

2) bake tools and baking efficiency: heat shrinkable tubes can be heated by electric hair dryer, heating trough, oven and other tools. In practical operation, the blast electric heating gun with mobile power supply is the most efficient and convenient to bake the shrinkage tube.

3) The shrinkage position and virtual shrinkage are insufficient. There are two requirements for the heat shrinkage position of the heat shrinkage pipe used as the lead sign: one is to be close to the cold-pressed terminal, and the other is that the shrinkage position of the three (or six or nine) leads should be basically even. If shrinkage causes virtual shrinkage (bottom below), after handling, dipping and curing, the shrinkage position of Suzhou shrinkage pipe may be uneven, slightly affecting the visual effect, seriously affecting the role of thermal shrinkage marking, or even falling off. The shrinkage of heat-shrinkable pipes made of insulating and sealing protective materials for special motors may cause the shrinkage position to move and affect the protection of the connecting end or cold-pressed end of lead wires and cables. In addition, it is better to inspect the shrinkage pipe when the material enters the factory, so as to avoid the phenomenon of insufficient shrinkage of the heat shrinkage pipe (it will not shrink when it reaches a certain temperature or rises again).

4) Adhesion and protection of impregnating paint: Because many motor manufacturers use epoxy impregnating paint to impregnate baking motor, in order to prevent the heat shrinkable tubes from adhering to each other during baking, the heat shrinkable tube cable must be fixed by appropriate methods before impregnating paint. The internal pressure mounting motor can use upper concave baffle to prevent adhesion.

5) Dirt and protection: The process of dipping paint, wiring of junction box and so on may dirty the label of heat shrinkable pipe. Therefore, the corresponding protection measures should be given and the inspection should be strengthened in the heat shrinkable process.

6) Heat-shrinkable pipe identification test: the identification letter test refers to JB62l3.1-92, > General Provisions for the First Part of Electric Winding Leading Soft Cable and Soft Wire > 8.1.2, > the shrinkage test refers to supplier enterprise standards, and the radial dimension test refers to ASTM designation: D876-80. Section 7 (Conical Thermal Steel Meter) measuring equipment.

Application of two heat shrinkable belt on motor

Insulation repair of L and lead cable

1) Repair of lead cracking and a little carbonization during welding: Due to factors such as lead material, manufacturing technology and improper operation during welding, partial cracking and a little carbonization will occasionally occur at one end of lead winding during gas welding between coil winding and lead cable, and heat shrinkage bandage is used to wrap up the lead winding. The heat shrinkable part can be used to enhance mechanical strength and insulation.

2) Restoration of bonding and tearing of lead wire during soaking and drying: Although the process requires that the shell of lead wire and outlet hole should avoid contact, and the contact between lead wire and rotating shaft should be avoided, it is difficult to guarantee in actual production. Once the motor stator and rotor are soaked and dried, the lead wire will be torn due to adhesion. At the same time, the "injured" part can be wrapped with thermal shrinkage belt, and then fixed by thermal shrinkage.

3) Repair of lead wire and cable during motor repairing and repairing: motor repaired before leaving factory, motor repaired during three-package period, etc. Any similar problems such as lead wire damage and cracking can be solved by thermal shrinkage.

2. TH handles rotor winding of motor rotor.

After connecting the copper flat lead wire of the insertion winding of the rotor with the collector ring and its insulation treatment, the group lead wire is wrapped with heat shrinkable tape, which plays the role of insulation protection, moisture proof and so on. It can improve the reliability and service life of the motor.


热缩材料在电机中的应用

    热缩材料按供货形状分为热缩管和热缩带,根据不同的用途及在电机不同的部位的应用为大家讲解热缩材料在电机中的应用问题。

一  热缩管在电动机上的应用

l、引接线标识系统

    由于热缩套管具有良好的电性能、铜稳定性、耐溶剂、耐浸渍漆腐蚀性,它的表面还可以按电机设计要求打上标识字母,所以在设计电机定子及其绕组附件引接线时可用热缩标识管代替传统的易脱落和易折断的金属铝片,做引接线标识系统。

    用热缩管做引接线标识设计引接线时,应考虑到热缩管的收缩率、各系列电机标识统一,以及使标识更醒目、美观等因素;具体规定热缩管的径向尺寸、打印的标识字母及其颜色、热缩管颜色。

2、特殊电动机做绝缘、密封保护

    H级电机电缆引出线温升较高,硅橡胶电缆有时质量不稳定等因素,H级电机定子引出线电缆绝缘部分采用热缩管绝缘保护,可提高电机的可靠性。

    热缩管具有耐腐蚀性(158℃,7天),线圈端部涂敷的三防覆盖漆又无法涂敷引出线,所以在TH处理电机定子引出线设计时其绝缘部分套机定子引出线设计时其绝缘部分套穿热缩管绝缘保护,可起到密封、防潮、防盐雾、防霉菌作用。

3、热缩管热缩工艺

    无论热缩管用做引接线标识还是特殊电动机引接线用做绝缘、密封保护材料,只有热缩工艺科学合理,能保证热缩管热缩可靠、实用稳定。下面是热缩工艺及其注意事项。

    1)径向尺寸设计与热缩爆裂:热缩管加热后沿径向产生50%以上的收缩,为保证套穿的热缩管热缩后牢牢地固定在载体上,其径向尺寸必须选择合适。径向尺寸过大,热收缩后固定不牢;径向尺寸过小,热缩及电机烘焙时容易导致爆裂。

    2)烘烤工具与烘烤效率:热缩管热缩可采用电吹风、加热槽、烘箱等工具。实际操作中,以配移动电源烘的鼓风电热枪烤热缩管,效率最高,使用最方便。

    3) 热缩位置与虚缩、缩量不足:用作引接线标识的热缩管,热缩位置有两个要求:一是要靠近冷压端子处,二是缩固在三根(或六、九根) 引接线上的位置应基本平齐。如热缩时导致虚缩(如下底部),在搬运、浸漆、热固化工序后,苏州热缩管的缩固位置可能参差不齐,轻微时影响视觉效果,严重时影响热缩标识作用,甚至可能脱落。特殊电动机用绝缘、密封保护材料的热缩管,虚缩可能导致缩固位置移动,影响引接线电缆连结端或冷压端的保护作用。另外在材料进厂时最好检验热缩管,避免出现热缩管缩量不足的现象(达到一定温度或再升温也不缩)。

    4)浸渍漆粘连与防护:由于许多电机制造商采用环氧型浸渍漆浸渍烘焙电机,为防止烘焙时热缩管彼此粘连,浸漆前必须将热缩管电缆用适当方法固定。内压装电机可采用上凹式挡板来防止粘连。

    5)脏污与防护:浸漆、接线盒接线等工序可能会弄脏热缩管标识,因此热缩工艺中应给出相应的防护措施并加强检查。

    6)热缩管标识检测:标识字母的检测参照JB62l3.1-92<<电机绕组引接软电缆和软线第一部分一般规定>>8.1.2款;缩量检验参照供应商企业标准;径向尺寸检验参照ASTM designation:D876—80.第7款(锥热  形钢计量计)测量设备。

二 热缩带在电机上的应用

l、引接线电缆的绝缘修复

    1)接线焊接时引接线开裂、少许炭化的修复:由于引接线材质、制造工艺、接线焊接时操作不当等因素,线圈绕组与引接线电缆气焊焊接时,引接线连结绕组一端偶尔会出现部分开裂、少许炭化现象,用热收缩带包扎处理 “受伤”部位,再热缩固定,可起到增强机械强度和绝缘作用。

    2)浸烘时引接线粘连撕开的修复:尽管工艺要求引接线与出线孔处机壳应避免接触、引接线与转轴避免接触,但实际生产中难以保证。一旦电机定转子浸烘时,引接线因粘连而撕裂,同时可用热缩带包扎“受伤”部位,再热缩固定。

    3)电机返修、维修时引接线电缆的修复:出厂前返修的电机、三包期内维修的电机等,凡是出现引接线损伤、开裂等类似问题,都可用热缩带来解决处理。

2、TH处理电机转子插入式绕

    组引出线绝缘保护转子插入式绕组铜扁引接线与集电环连接及其绝缘处理之后,用热缩带包绕,起绝缘保护、防潮等作用,可提高电机的可靠性及使用寿命。