how to avoid interior deterioration of gas pipe |
Posted: March 6, 2021 |
For gas pipe, interior deterioration is the electrochemical reaction of recurring water and also acid gas in the pipe comparable to galvanic cell and the chemical reactions that damage the steel lattice. Both of these reactions create the pipe wall surface to loosen, fall off and pierce, which can no more hold up against the pressure of natural gas in the pipe. In practical application, a sort of finishing can not be very good security, or can not meet the need such as anti-corrosion, climate resistance, great look, and also for that reason most several layer on metal surface layer interact to form a whole system, consisting of primer layer, the middle layer, paint, finishing one or numerous times each layer respectively as required, as well as there is just solitary layer such as powder coverings can meet the various needs at the very same time. The anti-corrosion coating of gas pipe should have the complying with residential or commercial properties: effective electric as well as water insulation; Not restricted by finishing methods; Good adhesion to pipeline surface; Resistant to harm during installation, storage space and transport; Resistance to chemical medium damages; Easy to fix; Long service; Environmentally pleasant and non-toxic. Currently, the anti-corrosion finishings for cross country transport pipes mainly consist of coal tar paint, 2LPE, 3LPE, merged epoxy powder (FBE), and double-layer integrated epoxy powder (FBE double-layer) finishing. Coal tar enamel. Coal tar paint coating is the very WLDSTEEL early secondhand layer, it's defined by good insulation performance, low water absorption, resistance to microbial corrosion and also plant origin penetration, lengthy life span and low price. However, its mechanical toughness is reduced as well as has a small ideal temperature level range, it may get away hazardous gases and requires rigorous smoke therapy. In the last few years, it has actually been slowly replaced by various other covering layers due to the limitation of environmental management. 2LPE. 2LPE has good insulation efficiency, low water absorption, high mechanical toughness, tough wear resistance, acid, antacids, salt and also bacterial corrosion, temperature level adjustment resistance. Nevertheless, there are likewise disadvantages: simple aging, inadequate attachment with the steel tube surface area, inadequate anti-cathodic removing efficiency. Electrostatic protecting of PE layer is not for exterior existing cathodic security. 3LPE. The three layers of PE anti-corrosion layer combine the benefits of high density polyethylene and merged epoxy powder. The epoxy powder is strongly incorporated with the surface of the steel pipe, and also the high thickness polyethylene is immune to mechanical damages. The sticky layer between both layers makes the 3 form a composite structure of molecular bond, which recognizes the good combination of rust resistance as well as mechanical homes. It is the front runner for large-scale gas transportation pipe design. Combination bound epoxy powder (FBE). The PBE layer has strong bonding with the surface of the steel pipeline, excellent insulation performance, high mechanical strength, temperature level change resistance and chemical corrosion resistance, and can be made use of in a variety of extreme environments. The major disadvantage is inadequate ultraviolet resistance as well as the thin overburden layer (0.35 ~ 0.50 mm). The double-layer FBE is similar to 3PE, with good compatibility, smooth surface area of the covering layer, which can prevent cathodic protecting. So, exactly how does the finishing safeguard the inner wall surface of the gas pipeline? We already understand that steel corrosion is due to the activity of the ecological tool on the metal surface area to generate electrochemical reaction or chemical reaction, the impact of the finish on the pipe is attained by preventing the above reactions:. ( 1) Shielding: Many finishes on acid, antacids, salt and other harsh media show chemical inertia, and the high dielectric constant to avoid the development of rust circuit, so the metal surface finishing to the steel surface area as well as the atmosphere isolation and shielding the destructive tool. It should be pointed out that the polymer coating is breathable and carefully related to its framework. ( 2) Passivation slow launch: With the aid of antirust pigment in the finish and also the metal surface response, make it passivation or create protective materials; In addition, numerous oils can also function as natural deterioration preventions by producing deterioration products under the catalytic action of metal soaps. ( 3) Electrochemical security: The coating potential is lower than iron steel filler (such as zinc) will give up the cathodic defense of the anode, and also the atmospheric rust items of zinc antacids zinc carbonate is fairly stable, can be shut, connect the last space. So exactly how to avoid the corrosion of the internal wall of the gas pipe? We can stay clear of by doing this: firstly, the gas removed from the ground experiences a collection of procedures such as desulphurization and dehydration, prior to it goes into the long-distance pipe. Second of all, the effective interior finish of the pipeline can reduce deterioration, gas transmission resistance and cleansing time.
|
||||||||||||||||
|