Pipeline & Plant Services

Pipelines usually involve work to be executed under difficult circumstances. Pipelines typically span long distances and can cross extremely rugged terrain such as hills, lakes, rivers, mountains, and even domestic areas. It is crucial that pipelines are tested for integrity, are leak free and cleaned and inspected on a regular basis. Omni Compressed Air, Ltd. can help by providing air or an inert gas (nitrogen) for complete pipeline commissioning maintenance and decommissioning for smooth pipeline operation during the entire life cycle of this valuable asset.

New pipelines and plants either undergo hydrostatic or nitrogen testing upon completion of construction. If any line was hydrostatically tested, water must be removed from the line before it is put into service. Air or nitrogen can be used to purge the pipeline and must usually meet a specified drying requirement. Cleaning or drying is done using a “pig” or series of pigs. Pig type selection is dependent upon pipeline design characteristics and degree of cleaning.

These Pigging systems are designed so the pig is loaded into a launcher that is pressured up to push the pig into the pipeline through a kicker line. In some cases, the pig is removed from the pipeline via the receiver at the end of each run. All systems must allow for the receipt of pigs at the launcher, as blockages in the pipeline may require the pigs to be pushed back to the launcher. Most of the time, systems are designed to pig the pipeline in either direction.

The pig is pushed either with air, inert gas (nitrogen) or liquid. If pushed by air or nitrogen, some systems can be adapted in the gas inlet in order to ensure the pig's constant speed, whatever the pressure drop is. The cleaning pigs push contaminants from the pipeline such as wax, foreign objects, hydrates and more that must be removed from the pipeline.

A major advantage of piggable systems is the potential product savings. At the end of each product transfer, it is possible to clear out the entire line contents with the pig, either forward toward the receipt point or backward to the source tank. There is no requirement for extensive line flushing.

Without the need for line flushing, pigging offers the additional advantage of a much more rapid and reliable product changeover. Product sampling at the receipt point becomes faster because the interface between products is very clear. Also the old method of checking at intervals, until the product is on-specification, is considerably shortened.

Omni Compressed Air, Ltd. has the experience and equipment to provide air and for plant service testing or as a propellant to push pigs through a pipeline for cleaning, purging and drying purposes. Omni also has the nitrogen membrane technology for plant pressure testing or to provide an inert propellant to push pigs through a pipeline. Our N2 Units are capable of 1500scfm of 95% to 99% pure nitrogen up to 2500 psi. Nitrogen is perfect for displacing oxygen, retarding oxidation, and preventing fires and explosions while performing major maintenance or improvements on pipelines.