A "pig" exits a liquid pipeline. |
A specialized launching system is custom-fabricated to facilitate entry of the "pig" into the pipeline. |
An industrial vacuum truck pulls a "pig" through a 6" line. |
Since before the 1870’s, commercial liquid products have traveled above and beneath the ground in pipelines of various sizes. After the bombing of Pearl Harbor in 1942, the U.S. government encouraged the construction of the Big Inch Pipeline from East Texas to the East Coast. This 24” diameter pipeline was twice the size of any previously built oil pipeline and was known as the War Emergency Pipeline.
After transporting crude oil for a couple of years, flow rates dropped and pumping pressures increased indicating that deposits on the inside walls of the pipeline were restricting flow. Different processes to clean these paraffin deposits inside the pipeline were employed and eventually the concept of sending an object through the pipeline to scrape the inside walls was considered. This gave birth to the modern practice of “Pipeline Pigging.”
A general definition of pigging is the propulsion of a mobile plug to execute certain activities inside a pipe or tube. The term “pig” may come from the squealing sound the plug tends to make as it travels tightly inside the tube. Early pigs were made of steel with a leather cover but today a wide variety of materials including poly and vinyl compounds are used. Multiple passes through the pipeline gradually remove unwanted deposits.
Bodine has experience in pigging pipelines of various sizes from 2” to over 20” in diameter. A typical pigging project involves pre-planning with safety as a central focus, followed by the construction of a launch tube and catch apparatus. The pig is loaded in the launch and a series of valves are changed to direct the liquid flow behind the pig.
The pressurized fluid acts to propel the pig through the pipeline to the catch area. This may be a few hundred feet or a number of miles. In some cases, the pig is pulled through the pipeline using Bodine’s industrial vacuum trucks. Both methods result in the removal of unwanted contaminates from the pipeline, yielding improved operational results for the client.
If you have a project where this unique cleaning method may be the solution, please give Bodine a call. Our sales professionals will be pleased to discuss your specific project with you.
