The modern system of capital repairs of the main oil and gas pipelines, based on advanced technologies and materials, modern equipment – creating an enabling environment to meet the increasing volumes of the repair work, as well as provides reliable and trouble-free operation of pipelines. Timely execution of these works on modern organizational and technological level is the key to longevity and safe operation of pipelines.
The basis of the concept of rehabilitation of pipelines is to support the operational reliability of the linear part of main pipelines due to carrier recovery pipe body and the ability to replace the insulating coatings.
To implement the project for repair of pipelines offers technological schemes of repair of trunk oil and gas pipelines:
- Stream pipeline repair with replacement of insulation in the trench with water jet automated complex removal of the old insulation, abrasive surface preparation and airless new polyurethane coating tube self-propelled machines.
- Repair of pipelines individual pits with replacement of insulation in the trench, without stopping the transportation of the product, with the use of mobile complex for the local repair of a water-jet removal of old insulation, abrasive surface preparation and application of the new airless polyurethane coating hand tools.
- Repair and recovery of individual pipes in the factory by using a water-jet removal of the old insulation, abrasive surface preparation and airless new polyurethane coating or applying three-layer polyethylene coating, cleaning the inner cavity of tubes and insulating inner surface, and chamfering the ends of tubes walls of pipes and repair.
Depending on the actual section of the pipeline status of the survey used a local repair method (non-stop product transportation), which is reduced mainly to the replacement of the insulation coating or overhaul method (with detached section of the pipeline), which is carried out with the partial replacement of pipes, full replacement of the insulation coating, restoration of electrochemical systems.
In cases when major repairs must be carried out only re-insulation of the pipeline this work must be performed in field conditions using modern cleaning and insulating equipment. At the same time as the equipment used for local repairs (re-isolation of individual sections, valve stations and other individual elements of pipeline systems), as well as equipment for in-line overhauls.
In addition to performing complex repair in field conditions is widely used method of repair, in which the pipe section being repaired pipeline transported to a specialized factory which produces the whole range of activities, including the removal of old insulation, pipe body diagnosis, removal of defects, machined ends, the application of a new polyurethane or polyethylene extrusion coating insulation, certified remanufactured tubes.
Using remanufactured factory pipes significantly reduces the capital cost of construction and installation work in providing quality assurance and regulatory life of the facilities, as well as increase the pace of work on capital construction and repair up to 2 times.