Removing Soft to Medium Wax from Pipelines
Many pipelines become affected with a build-up of soft to medium wax which will reduce the efficiency of the pipeline due to the reduced bore in the pipe. In addition, increased friction, caused by the uneven surface of wax deposition in pipelines, will result in turbulent flow through the pipeline. A build up of wax in a pipeline can also drastically increase the costs of transporting oil due to the increased energy required by the pumps to overcome the reduced pipeline efficiency.
Pigtek Ltd can provide specialist cleaning pigs to remove and recover soft to medium wax from crude oil pipelines and thereby restore the pipeline to maximum efficiency and capacity.
The Pigtek de waxing pigs generally incorporate specially moulded discs that are designed to scrape wax from the internal pipewall. These discs can be supplied in various diameters, profiles and hardness depending on the type of deposition to be removed and the type of pipeline the pig is to be used in.
Brushes can also be used in some cases to enhance the cleaning efficiency of the De-Waxing pigs.
ByPass is extremely important when cleaning wax from crude oil pipelines to ensure that the loosened wax is flushed ahead of the pig. The bypass may be fixed (where bypass ports are opened before the pig is introduced into the pipe), or may be variable i.e. where one or more bypass valves are incorporated into the pig body – for further information on by-pass valves please click here to see our Advanced Bypass Pig.
Removing Hard Wax and Asphaltenes from Pipelines
Some crude oil pipelines are affected by a build-up of hard wax, sometimes known as asphaltenes. This is a very hard type of deposition and is generally unaffected by the passage of most types of cleaning pigs.
To remove hard wax from crude oil pipelines, more aggressive pigs will need to be utilised. Often this will include scraper pigs such as the Pigtek Hard Deposit Removal (HDR) Pin Pig or the Pigtek Heavy Duty Brush Cleaning Pig – for more information about these heavy-duty cleaning pigs, please click here and here.
As no two pipelines are the same, often a combination of pigs will be required to carry out wax deposition cleaning. Pigtek can supply a comprehensive “toolbox” of special cleaning pigs and spares for this task and we pride ourselves in being at the cutting edge of pigging technology advances.