Pipe cleaning pig characteristics and selection method
Pipeline cleaning pigs are the main equipment for oil pipeline cleaning. Today, we will talk about the characteristics and selection methods of pipe cleaning pigs. I hope to help everyone.
Pipe cleaning pig characteristics
Foam pigs use a jet of air to create a vacuum that adsorbs moisture into the soft foam and discharges it to the front of the pig. The sealing function of the rear end plate is used to absorb, carry and spread moisture, and the purpose of drying the pipeline is completed.
The soft foam of the foam pig mainly acts as a carrier for adsorbing moisture, and the rear end plate acts as a seal. Structurally, the rear end plate is made of a polyurethane injection molded material, which serves as a sealing function, and can carry and push the accumulated water in the pipeline to a greater extent. It has good plasticity and is not formed by the formation of the pipeline. Affect the seal. A replaceable filter screen is installed at the end of the intake pipe to prevent the dirt from entering the pipe and blocking the jet nozzle. The front end of the pig is a polyurethane foam, and the sieve support skeleton is embedded in the foam, so that the intermediate absorbent foam can be fixed and replaced, and the inlet and the rear end plate of the sieve support skeleton are fixed, so that the whole pig Become a detachable combination.
The magnetic pig is composed of a metal steel body, an electronic transmitter, a polyurethane (rubber) cup, a permanent strong magnet, and a magnetic brush. It is suitable for removing iron scraps, electrode heads and other impurities in the pipeline. The magnetic pig is characterized in that the magnetic brush is arranged close to the pipe wall according to the magnetic flux leakage principle, so that the pig has the ability to change when passing the curved pipe and reducing the diameter. In order to achieve excellent cleaning results for pigs, it is recommended to use a double-body pig (two pigs are connected with a universal joint), and different combinations of cups and straight plates can be made according to distance requirements.
The straight pig consists of a metal steel body, an electronic transmitter, a polyurethane support plate, and a sealing plate. It has the functions of two-way walking, cleaning, isolation, water blocking, etc. It is especially suitable for pipelines, submarine pipelines, pipelines that are inconvenient to open after jamming, and should not be stopped after being put into production. It has the characteristics of good sealing and thorough cleaning.
Pipe cleaning pig selection method
Pipeline cleaning pig selection is a multi-objective, multi-factor decision-making problem that mainly determines the mechanical strength, wear resistance, adsorption of pigs, the reactivity of the transport medium in the pipeline, and the ability to pass through, as follows:
Pilot target
The pipeline cleans up liquid or solid impurities and predicts the amount of dirt. If it is expected that there are many impurities in the sediment, the natural gas pipeline may be pigs with a discharge hole, and the sand is blown up by the gas of the discharge hole to avoid clogging.
Pipeline life cycle
The new pipeline is to clean up the residue, preliminary measurement, pressure test, drying and trial operation. Running the pipeline is to clean up wax deposits and dirt, media isolation, and corrosion inhibition. Pipeline shutdown is the removal of media and filling of inert gas.
Determine the driving medium (oil, water, gas) characteristics of the pigging.
Pipeline clean pig interference
Consider the minimum bend radius of the pipe and the bend angle, the minimum and maximum inner diameters, the branch pipe connections, the elevation changes along the line, and the type, location, size, etc. of the valve/three-way/elbow along the line.
Pipe cleaning process
The drive pressure range values provided by the pipe (maximum allowable operating pressure of the pipe, pipe operating pressure, temperature parameter changes), and the range of possible speed values for pipe cleaning pigs and the maximum distance the pipe cleaning pigs must run.
The above is about the characteristics of pipe cleaning pigs and the selection method. I hope everyone can understand the characteristics and selection methods of pipe cleaning pigs.
