Ukrnafta opens modern ESP repair shop
Ukrnafta opens modern ESP repair shop

On December 22 new facilities to repair electrical submersible pump installations (ESP) were opened at the production base (Pryluky) of PJSC "Ukrnafta" Oilfield Services Department. This modern facility is the only one in Ukraine that performs incoming inspection of new ESP installations and repairs of ESP installations with the issuance of a computer-aided inspection protocol.

The base is equipped with the newest equipment (made in the USA, Germany, Great Britain), which is located in the production areas so that it could be audited by potential foreign customers, with whom preliminary negotiations on cooperation are held, and, if necessary, to pass certification of the American Petroleum Institute (API).

The capacity of the new workshop allows to perform incoming inspection of new ESP installations and the whole cycle of ESP repair: to repair motors, hydraulic protectors, pumps, cables and other components of ESP installations. All this is performed in accordance with the manufacturer's indicators - after the repair the unit should completely comply with the factory parameters.

According to the type of work, facilities are divided into:

  • repair section for pump sections and hydraulic guards;
  • repair section for submersible motors;
  • repair section for cables and cable extensions.

The organisation of work at the repair section for pump sections and waterproofing includes three stages:

  • first - where the equipment is washed externally and internally, disassembled and defective parts and elements of the equipment;
  • the second stage is reassembly, where the equipment is directly assembled from the checked parts;
  • the third stage is verification of the overhaul carried out on computerised test benches where a report is generated.

The quality of the repair is evidenced by a protocol generated by the computer without human intervention. There are also test benches at the first section to check the waterproofing and the pump sections. In particular, the ESP test bench allows taking real-time measurements of pressure and flow rates and other parameters. The hydro-protection test bench allows the testing of all parameters, including those under load.

The submersible motor repair (SM) area also has a fully closed circuit. First, the motor is disassembled and the winding is removed. Next, there is an area for internal washing of the submersible motor stators and internal washing of the shafts. Next to the box are two ovens for drying SM stators. Each oven has the capacity to dry 6 stators up to 9 metres long at the same time. The impregnation box is designed for simultaneous impregnation of two SM stators. The base is also equipped with two stator winding lines. One of the stator rewinding lines is limited to 6 metres, the second line can be extended up to a maximum length of 9 metres of the stator to be repaired. The submersible motors are tested after repair. A computerised test bench allows the operation of the submersible motors to be tested, both in no-load and under load. All parameters after the repair are recorded in the protocol.

At the cable repair section, 4 lines have been installed and commissioned. The lines allow repair of cable drums with total weight up to 10 tons.

The organisation of work in the workshop was completely changed, with a clear separation of processes. That is, workers who dismantle / defect / assemble / check the component parts of the ESP unit, deal only with their part of the repair and do not pass on to the next stage. This distribution of duties contributes to quality control of the finished product - each worker follows the previous one and promptly fixes all the inaccuracies (if any).

Modern repair technologies in the production base shop (Pryluky) will increase the time between overhauls of the wells and reduce the costs per tonne of oil produced. This is one of the main indicators for the company, which determines the efficiency of operations and the cost of production.