Exactly How To Stop Inner Deterioration Of Natural Gas Pipeline

For gas pipeline, internal deterioration is the electrochemical reaction of residual water and also acid gas in the pipeline comparable to galvanic cell and also the chain reaction that damage the metal latticework. Both of these responses trigger the pipe wall to loosen up, fall off as well as pierce, which can no longer hold up against the pressure of gas in the pipeline. In practical application, a type of finishing can not be very good defense, or can not satisfy the requirement such as anti-corrosion, climate resistance, good appearance, and for that reason most numerous layer on steel surface finish collaborate to form an entire system, consisting of guide layer, the center layer, paint, covering one or numerous times each layer respectively as required, and there is just single layer such as powder layers can satisfy the various requirements at the very same time.

The anti-corrosion finishing of natural gas pipeline ought to have the complying with residential or commercial properties: reliable electrical and water insulation; Not restricted by covering techniques; Good adhesion to pipeline surface; Resistant to harm throughout installation, storage and transport; Resistance to chemical tool damages; Easy to fix; Long solution; Environmentally friendly and also safe. Today, the anti-corrosion layers for long distance transport pipelines mainly include coal tar paint, 2LPE, 3LPE, integrated epoxy powder (FBE), as well as double-layer fused epoxy powder (FBE double-layer) finish.

Coal tar enamel.
Coal tar paint layer is the early used finishing, it's defined by good insulation performance, low water absorption, resistance to microbial corrosion and also plant root infiltration, lengthy life span and low cost. Nevertheless, its mechanical stamina is low and has a little appropriate temperature level range, it might leave toxic gases and requires strict smoke therapy. Over the last few years, it has actually been progressively changed by other covering layers because of the constraint of environmental management.

2LPE.
2LPE has excellent insulation efficiency, low water absorption, high mechanical strength, challenging wear resistance, acid, antacids, salt and bacterial deterioration, temperature level change resistance.
Nevertheless, there are also disadvantages: simple aging, poor adhesion with the steel tube surface, poor anti-cathodic removing performance. Electrostatic protecting of PE layer is not conducive to exterior present cathodic defense.

3LPE.
The three layers of PE anti-corrosion layer integrate the benefits of high thickness polyethylene and also integrated epoxy powder. The epoxy powder is firmly incorporated with the surface of the steel pipeline, and the high thickness polyethylene is resistant to mechanical damage. The sticky layer between both layers makes the 3 type a composite structure of molecular bond, which recognizes the excellent combination of deterioration resistance as well as mechanical residential properties. It is the first choice for massive natural gas transport pipeline design.

Fusion adhered epoxy powder (FBE).
The PBE finishing has solid bonding with the surface area of the steel pipe, good insulation performance, high mechanical toughness, temperature level adjustment resistance and also chemical corrosion resistance, and also can be made use of in a range of harsh settings. The main drawback is bad ultraviolet resistance and the thin overburden layer (0.35 ~ 0.50 mm). The double-layer FBE is similar to 3PE, with great compatibility, smooth surface of the covering layer, which can stay clear of cathodic securing.

So, just how does the layer protect the internal wall of the gas pipe? We already understand Read More Here that metal rust results from the action of the ecological tool on the steel surface to create electrochemical response or chain reaction, the impact of the covering on the pipe is achieved by preventing the above reactions:.
( 1) Shielding: Many coatings on acid, alkali, salt and various other harsh media show chemical inertia, and also the high dielectric constant to avoid the development of corrosion circuit, so the steel surface area covering to the steel surface area and also the environment isolation and also securing the destructive medium. It must be explained that the polymer coating is breathable as well as carefully related to its framework.
( 2) Passivation sluggish release: With the assistance of antirust pigment in the layer and the steel surface area reaction, make it passivation or create protective substances; In addition, many oils can additionally function as organic corrosion inhibitors by generating destruction products under the catalytic action of steel soaps.
( 3) Electrochemical security: The finish potential is lower than iron metal filler (such as zinc) will certainly compromise the cathodic defense of the anode, as well as the climatic corrosion products of zinc alkali zinc carbonate is reasonably steady, can be shut, connect the last space.


So how to prevent the rust of the internal wall of the gas pipe? We can avoid by doing this: first of all, the gas extracted from the ground undergoes a collection of processes such as desulphurization and dehydration, before it goes into the long-distance pipeline. Secondly, the effective interior finishing of the pipeline can lower deterioration, gas transmission resistance and also cleaning time.