Operating under a single project management team to ensure optimal safety, quality and schedule efficiency, we support our clients with detailed planning, coordination and execution for various scopes of construction completion, pre-commissioning and commissioning activities such as pressure testing, water flushing, air blowing and drying. In addition, our highly experienced, multidisciplinary experts undertake many specialist activities such as chemical cleaning, lube oil flushing, hydro jetting, pneumatic testing, helium / nitrogen leak testing, inspections and other associated actions within the construction environment. Pretesting natural gas lines follows an ordered set of steps which allow for satisfactory performance analysis. Highlighted below are the key components of pipeline pre-commissioning and commissioning.
A significant majority of newly constructed pipelines will require initial cleaning before they can be cleared to deliver their intended payloads. Pipeline cleaning services can be carried out both at the pre-commissioning and commissioning phases of final testing. Flushing out natural gas lines can be done with the help of mechanical devices (pigging) or chemically by forcing chemical compounds through the pipeline channels.
During a pigging operation, a device called a pig is driven through the interior of the pipeline system to clean it and flush out retained impurities. Pig devices can be used in new as well as in-service pipelines to help remove debris and halt the onset of corrosion.
Hydrostatic testing involves passing a liquid through the newly constructed pipelines to detect areas of leakage. Water containing a dye is the typical medium utilized in this test. This type of screening test is the most commonly used method of checking for pipeline integrity. Additionally, altering the pressure of the fluid during the hydrostatic test procedure for pipelines can help determine unusual pressure bleeding. A modified form of hydrostatic pressure testing can be done at intervals to ensure sustained flow line integrity.
Hydrostatic testing processes leave moisture within the pipelines they check. The presence of vaporized water within the lumen of pipelines constitutes a potential impurity for fluids that are transported through them. Pipeline drying services will remove the retained moisture from within the pipes and ensure the quality of the products transmitted through them.
A vital aspect of natural gas pipeline commissioning procedures is the purging of flow lines. Atmospheric air present within newly forged pipelines will alter the quality of their intended gaseous or liquid cargo as it contains suspended impurities. Pipeline purging is done as part of commissioning procedures and it involves using an inert gas (usually nitrogen) to replace the air contained within the flow line lumen. Nitrogen purging is an effective and cost-efficient method and can be carried out using on-site nitrogen generators.
This process involves the use of a high-volume vacuum to manipulate the pressure within the pipeline system. At pressure levels 40 Torr or below, water deposited within the flow lines will vaporize and can then be displaced leaving the moisture content within the pipelines at minute quantities. The remaining moisture can then be eliminated by purging the lines with an inert gas.
Nitrogen Drying & Preservation
The importance of properly drying pipeline networks cannot be overemphasized. Poorly dried pipelines are at a higher risk of corrosion, hydrate formation, and blockage. Utilizing nitrogen-based drying to clear out moisture will limit the onset of potentially hazardous leaks and minimize the cost of pipeline maintenance services.