The planning stage of pipeline construction revolves around having engineers design blueprints and having the project site surveyed. Numerous factors are considered during this phase including type, size, and composition of pipeline, and processes that will be used to minimize environmental impact.
During the pre-construction planning, project owners have to obtain bids from qualified pipeline contractors. Selected contractors have to obtain proper permits and insurance and secure easement rights prior to breaking ground.
The construction phase is divided into three stages. The first involves clearing and grading the land and digging trenches. The second encompasses stringing and welding pipes, then installing the connected pipes into trenches. The final phase involves testing the pipeline; backfilling trenches; and restoring the land to its original condition.
Pipeline companies use the method of subsurface utility engineering to locate the position and depth of previously installed pipes and utilities. Being able to determine the location of existing pipeline helps contractors to avoid project delays, minimize construction costs, and provide a safer work environment.
Construction crews have to clear and grade the site to provide a right-of-way for trenching procedures. Segments of pipe are shipped to the site via semi trucks. Crew members then string the pipes together on the ground and welders have to weld pipes before they are placed into trenches.
Welded pipes are put through extensive tests to make certain they have sufficient integrity. Once pipes pass inspection, workers apply an epoxy coating to prevent welds from leaking.
One of the more challenging tasks is lowering pipes into trenches. This job requires operators to be highly skilled in order to precisely place pipes into position. The type of testing pipes undergo is based upon the application being used. Sewer pipes and fireline endure different kinds of tests than natural gas or petroleum pipelines.
Construction sites and pipes are subject to frequent inspections during the construction phase. Inspectors also validate that pipeline contractors hold appropriate permits, licenses, and insurance policies and possess legal documents pertaining to easement agreements and landowner rights.
Upon project completion, the construction site has to be monitored to make certain irrigation and drainage systems work properly and to identify potential problems.
Pipeline installation typically involves coordinating the project with several contractors. Industrial and municipal jobs usually require dozens of construction workers to complete the work.
It is critical to hire pipeline construction companies that possess experience with the specific type of installation and capable of coordinating their work with other contractors. Pipeline projects are categorized as either wet or dry utility. Although a few contractors are experienced in both fields, most specialize in one area or the other.
Dry utility pipeline construction involves installing pipes that convey natural gas or protect utilities, such as telecommunications and electrical, from environmental elements.
Wet utility contractors install pipes that convey liquids such as water and sewer pipes, storm water drainage systems, and petroleum-based products.
One essential consideration of pipeline construction is being able to obtain sufficient pipes to finish the project. The tsunami disaster that struck Japan has created a shortage of products used to manufacture pipes. The rising cost of crude oil, fuel, and the materials required for manufacturing HDPE resin has resulted in significant increases in pipeline pricing.