Technology of pigging and gauging the pipeline upon its laying
Key concept – thorough cleaning of the laid pipeline from con-struction waste, electrode residue and foreign objects, as well as calculating the minimum run-in clearance, i.e. pipeline gauging. The technology includes mechanical cleaning of the pipeline, using cleaning pigs, run by the flux of air or process water (by agreement with the Client). The cleaning pig should possess a transmitter or, for pipelines of O=114 mm, 159 mm, 219 mm, 273 mm and 325 mm, the transmitter-combined cleaning pig should be used. The process of cleaning and running of the cleaning pig is additionally monitored by the acoustic mole “VOSTOK-AL” or “VOSTOK-ALR”.
Cleaning pigs may be equipped with brushing, magnetic or gauging units for the purpose of cleaning the pipeline interior from scale, electrode residue and metal fractions, as well as calculating the minimum run-in clearance of the pipeline.
The work includes the preparatory stage, the core stage and compiling the technical report (when necessary).
- 1. PREPARATORY STAGE
- 1.1. Research of the pipeline technical documents.
- 1.2. Inspection of the route, selection of check points for moni-toring the cleaning pig’s running.
- 1.3. Calculation of cleaning pig’s transit time.
- 1.4. Preparation of cleaning pigs and monitoring devices.
- 1.5. Transportation of cleaning pigs and monitoring devices to the work location.
- 1.6. Verification of equipment operation capability at the work location.
- 2. CORE STAGE
- 2.1. Kicking of cleaning pig into the launcher station, station pressurization, and verification of transmitter operation capability after the pressurization.
- 2.2. Launch of the cleaning pig, control of its departure from the launcher station and start of tracking along the route.
- 2.3. Tracking the run of a cleaning pig in the pipeline, register-ing the time of its transit through the check points.
- 2.4. Control of the cleaning pig’s arrival to the catcher station and identifying its location in the station.
- 2.5. Retrieving the cleaning pig from the catcher station, wash-ing the pig.
- 2.6. Transportation of the equipment to the depot.