A plastic product may be made of a variety of materials or parts. To combine the components, mechanical fixings, adhesives and welding processes can be used. In the three ways of bonding, the best welding process and various welding forms can be applied to different welding processes according to different materials, sizes and purposes.

机械固定件、粘合剂和焊接工艺均可将两种工程塑料接合。机械固定件可快速将两种部件连接，但接缝的防漏功能较差，局部应力也会使聚合物材料之间脱离。

Two kinds of engineering plastics can be joined by mechanical fixers, adhesives and welding processes. The mechanical fixer can quickly connect the two parts, but the leakproof function of the joint is poor and the local stress will disconnect the polymer materials.

粘合剂可提供良好的特性，形成防漏功能优良的接缝，可是，粘合剂处理难度较大，固化速度慢。同时，采用粘合剂粘合时，接缝准备和表面清洁度要求较高。

The adhesive can provide good properties, forming good seams of leakproof function, but the adhesive treatment is difficult and the curing speed is slow. At the same time, the preparation of the joint and the surface cleanliness are higher when the adhesive is used.

焊接可产生粘合稳固的接缝，其机械特性接近于母体材料。塑料焊接仅限于热塑性聚合物，原因在于热塑性材料可通过加热而软化。热固性聚合物在硬化之后，无法通过加热而软化。与金属相比，热塑性聚合物焊接所需的热量较少。

Welding can produce a solid bonding joint, and its mechanical properties are close to the parent material. Plastic welding is limited to thermoplastic polymers because the thermoplastic materials can be softened by heating. After hardening, the thermosetting polymer can not be softened by heating. Compared with metal, thermo plastic polymer welding requires less heat.

塑料焊接工艺可分为两类：

The plastic welding process can be divided into two categories:

A）机械移动式焊接工艺：超声焊接、摩擦焊接和振动焊接。

A) mechanical mobile welding technology: ultrasonic welding, friction welding and vibration welding.

B）外部加热式焊接工艺：热板焊接、热气焊接和植入焊接。

B) external heating welding technology: hot plate welding, hot gas welding and implant welding.