The determinant of anti-corrosion and rust removal of Seamless Stainless Steel Tube
Seamless Stainless Steel Tube has strong corrosion resistance and is easy to process into various shapes of steel. It has good welding performance and no tendency to be cold and brittle. Therefore widely used.
The stainless steel seamless pipe does not undergo a phase change, wherein the heat treatment is to heat to a high temperature to solidify during the process. The stainless steel seamless tube has a low thermal conductivity, and the thermal conductivity can be increased after rising to a high temperature. Stainless steel seamless pipe heating is based on the solid solution rate of the carbide. The 304 stainless steel carbide takes 3 seconds at 1065 degrees Celsius, 1.5 seconds at 1176 degrees Celsius, and 10 seconds at 1000 degrees Celsius. From this point of view, the higher the heating temperature of the stainless steel seamless pipe, the better. However, the higher the heating temperature, the other defects occur at the same time. Will result in a decrease in tensile strength.
Stainless Steel Tube ASTM A268 anti-corrosion method
1.cleaning
Solvents and emulsions are used to clean the surface of the steel to remove oil, grease, dust, lubricants and similar organic matter. However, large-diameter seamless steel pipes cannot remove rust, scale, flux, etc. on the surface of the steel, so only in anti-corrosion production As an aid.
2.tool rust removal
The surface of the steel is mainly polished by using a wire brush or the like to remove loosened or lifted scale, rust, welding slag, and the like. The large-diameter seamless steel pipe manual tool can achieve the Sa2 level by rust removal, and the power tool can achieve the Sa3 level by rust removal. If the steel surface has a strong iron oxide skin, the tool rust removal effect is not ideal, and the anchor depth required for anti-corrosion construction cannot be achieved.
3.pickling
Generally, chemical cleaning and electrolysis are used for pickling treatment. Pipeline anti-corrosion is only chemical pickling, which can remove scale, rust and old coating, and can sometimes be used as re-treatment after sandblasting and rust removal. Although chemical cleaning can achieve a certain degree of cleanliness and roughness, its anchor pattern is shallow and it is easy to pollute the environment.
4.jet rust removal
The jet rust removal is driven by a high-power motor to rotate the jet blades at high speed so that the abrasive grains such as steel grit, steel shot, wire segment, and mineral are sprayed under the action of centrifugal force, which can completely remove rust, oxide, and dirt. Moreover, the steel pipe can achieve the required uniform roughness under the action of abrasive violent impact and friction.
Stainless Steel Tube ASTM A268
After the spray rust removal, not only the physical adsorption of the surface of the pipe can be enlarged, but also the mechanical adhesion of the anticorrosive layer to the surface of the pipe can be enhanced. Therefore, jet descaling is an ideal way to remove corrosion from pipelines.Treatment of surface cracks in stainless steel pipes:
1. Forced cooling is achieved by appropriately increasing the casting speed and increasing the amount of cooling water, increasing the water flow rate, and lowering the water temperature within a certain range.
2. Improve the accuracy of the arc of the large-diameter seamless steel pipe casting machine, avoid excessive stress on the solid-liquid interface at the initial stage of solidification, and prevent cracks along the grain boundary.
3. Strictly control the composition of steel grades, especially the control of carbon content.
4. Increase the electromagnetic stirring of continuous casting. The superheat of the medium-clad steel is controlled below 40 °C.
The above is all the content for everyone, I hope to help everyone. If you want to know more, you can browse our website, our company is Seamless Steel Pipes Supplier and we will provide you with more professional information.
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