It believes the spheres are probably the largest of their type ever manufactured.
The 56-in spheres were manufactured from a three-piece core, which was then suspended in an outer mould, enabling the outer skin to be cast in one piece. PE’s proprietary Omnithane polyurethane was used to provide low-abrasive and high-tensile characteristics. The main challenge was to build suitable tooling that ensured equal temperature dissipation so that the polyurethane, once poured, would cure at an equal rate and would therefore not be prone to tear propagation, a common problem with many types of sphere on the market.
In addition to the spheres, PE is providing on-site services to train clients’ personnel, due to the large weights (2 tones each) and sizes involved, to ensure safe and trouble-free operation..
This item is reproduced courtesy of the Pigging Products & Services Association: www.piggingassnppsa.com.
Light-weight pigs help remove black powder
WORKING with a major pipeline operator, PE was asked to develop a new generation of pigs for large gas lines which would help remove black powder. Due to the arduous conditions of the dry-gas lines, in conjunction with long runs and large diameters, in this case up to 56in, PE’s client found that conventional designs were unsuitable for its operational cleaning requirements, particularly in removing the powder.
The challenge was to reduce the pig weight, while still allowing for all the required features, such as magnets for ferrous debris collection, additional discs for debris removal, and correct centralization along with high-density brushes for fine-powder removal. In addition, the pigs had to be run in high-production flowrates, and special bypass and jetting facilities were incorporated to control their speed and allow sufficient bypass to run the pigs without any interruption to production.
To reduce the pig weight, new body tube designs and special alloys were used, reducing the weight by up to 50%. To cope with the high abrasive conditions in the dry-gas lines, suspension wheels, mounted on a newly-designed trailing arm, were also incorporated. The new designs also used PE’s proven Hyper Omnithane polyurethane to minimize the wear on the discs.
This item is reproduced courtesy of the Pigging Products & Services Association: www.piggingassnppsa.com.