anti-corrosion steel pipe is a common steel pipe. to slow down and prevent the corrosion and depreciation of the steel pipe under the chemical and electrochemical action of internal and external media, or due to the metabolism of microorganisms, it is necessary to do a good job of anti-corrosion of the pipeline. in addition to the corrosion protection technology for the transport medium, most steel pipes for transporting oil and gas are in a relatively complex soil environment, and the transport medium is also corrosive, so the inner and outer walls of the pipeline are likely to corrode. once the steel pipe is corroded and perforated, it will cause oil and gas leakage, which will not only seriously pollute the environment, but also cause fire and endanger people. therefore, it is necessary to do anti-corrosion work on the pipeline. however, there are many insulation methods for anti-corrosion steel pipes, and different methods must be selected according to different types.
1. ways to keep warm
mainly use uncertain insulation materials (such as expanded perlite, expanded frog stone, asbestos powder, asbestos fiber, and diatomite clinker, etc.), and add a certain amount of binder (such as cement, water glass, and refractory clay, etc.). or add a coagulant (such as sodium fluorosilicate or nepheline aminopyrine) to it, select the proportion of ingredients, add water and mix evenly to form a shaped mud mass, and then spread it evenly with your hands. keep warm for smearing.
2. wrapped insulation
①the winding heat preservation method is mainly to make the heat preservation material into a rope or strip shape, and then directly wind it on the pipe that needs heat preservation.
②the main insulating materials using this method in daily life are: slag wool felt, glass wool felt, straw rope and asbestos belt, etc.
3. prefabricated components for insulation
①pipeline prefabricated insulation structure. when the pipe diameter is dn≤80mm, use a semicircular shell. if the pipe diameter is dn ≥ 100mm, fan-shaped or trapezoidal tiles are used.
②materials used in prefabricated products are mainly foam concrete, asbestos, slag wool, glass wool, expanded perlite, calcium silicate, etc.
4. filling method heat preservation
① if the insulating material is bulk material, this method can be used for detachable insulating material.
② during the construction process, fix the round steel support ring on the pipe wall. the thickness of the ring is the same as that of the insulation layer, and then the support ring is wrapped with an iron sheet, aluminum sheet, or wire mesh to fill the insulation material.
③ this filling method can use prefabricated hard arc bricks with porous materials as the supporting structure, and the distance between them is about 900mm, just like plain wire mesh, according to the outer circumference of the insulation layer of the pipe, the slag is processed by a circular machine by covering the perimeter of the support, the filling and insulating structure should be made as far as possible from a metal protective shell.