Gas and oil provide over 50 percent of the nation’s energy. In one year alone, the United States produced over 500 million metric tons of oil and over 700 billion cubic meters of natural gas. Both oil and gas are transported through hundreds of miles of pipelines. These pipelines must be carefully cleaned and maintained to make sure the oil and gas is pushed through safely. To help keep these pipelines clean, oil and gas companies employ something known as a “pig” to sweep through the pipeline and keep it clean and free of any possible obstructions.
In the pipeline industry, a “pig” is a cylindrical device featuring large discs (made of varying materials, but often rubber) that scrape against the sides of the pipe. This in turn creates a “squealing” sound reminiscent of a pig, hence the name of the device. A pig valve is a special type of high pressure valve that can, depending on the need, catch, release, or receive a pig. Pig valves, which include variations like a shut off pig valve, are located at specific points in the pipeline. They are high pressure valves that are built to withstand the immense pressures that can be found inside a gas or oil pipeline. The shut off pig valve can also work something like a gate valve in that it can shut off the flow of gas or oil temporarily.
As stated before, the purpose of the pig valve is to catch, release, or receive a pig before or after it heads off on its cleaning duties. The idea is that the pig can be inserted in one end of the valve and then be turned so that it can be launched into the pipeline to head off on cleaning duties. Since the pig is placed inside the pipeline, it needs to be built to withstand and handle high pressure.
In conclusion, a shut off pig valve is an essential piece of equipment to have for any pipeline. By installing a shut off pig valve, it is possible to insert or remove a pig relatively easily. In order to work as well as possible, a shut off pig valve should be built to the highest of specifications so it can handle high pressure, torque, and other stresses that can occur inside a pipeline.
