Pipeline Pig Traps (Receivers and Launchers)

Pig launchers and receivers

猪发射器本质上是用于发射的船只pipe pig或猪工具进入管道，以进行清洁或检查目的。在进入管道中后，通过驾驶液将猪工具推开管道。通过从猪刷动动作的过程中清洁管道。另一方面，猪接收器接收了猪工具。猪接收器也是用于接收管道猪工具的容器。猪发射器和接收器旨在满足管道的特定要求。

Pig traps can be of horizontal, vertical or inclined type. For ease of operation, horizontal pig traps are preferred. When space constraints become critical, vertical or inclined pig traps are installed instead of horizontal.

The schematic shown here is for a horizontal pig launcher. A horizontal pig receiver would be almost identical to this schematic, except for the position and size of certain nozzles such as drain, kicker line and PSV nozzle.

Structure of pig receiver / launcher

For any pig trap, be it horizontal, vertical or inclined pig launcher or receiver, basic structure is similar and consists of -

1. Major barrel which is larger than the pipeline size

2.与管道尺寸相匹配的小枪管

3.连接主要桶和小枪管的还原桶

4. A quick opening door on the major barrel end of the pig trap

5. Full bore ball valve on the minor barrel end of the pig trap

6.遵循喷嘴 - 踢球线，缓解线（PSV），小桶和主要枪管上的压力表，小桶上的猪信号器，清除连接，排气和排水管。

7. As a safety measure, quick opening door should be mechanically interlocked with isolation valves on kicker line and main line, so that the door cannot be opened when pig trap is still connected to these pressurized lines. This safety precaution can also be accomplished by interlocking the door with vent or depressurizing line, so that the door can be opened only when the pig trap is depressurized.

For vertical pig traps, the reducer barrel is of concentric type, so that the center lines of major and minor barrels match with each other. Vertical pig traps are always installed to have the major barrel above the minor barrel. The tentative position of the nozzle shown in the schematic, may change for vertical pig traps.

Important details and dimensions for design of a pipeline pig trap

Following certain dimensions are important for pig trap design and have to be specified in the pig trap datasheet, before sending it to the supplier.

1. Major barrel size and length
2. Minor barrel length and size (same as pipeline size)
3. Reducer barrel length.
4. Inclination type of pig trap (horizontal or vertical)
5. 在水平管道猪陷阱的情况下
6. Location of certain nozzles such as Kicker line, Relieving line, drain, vent, pig signaler.