Rust-Removing maintenance method for straight seam welded pipe
- Apr 24, 2018 -

However, the straight seam welded pipe equipment for the maintenance of the problem is a headache. Longitudinal welded pipe equipment plays an important role in life and work. It is generally required that the surface of straight welded pipe fittings reach near-white level (Sa2.5 practice has proved that the construction technology of epoxy, vinyl, phenolic and other anticorrosive coatings commonly used in longitudinal welded pipe fittings. With this descaling grade, you can almost eliminate all the oxidized skin, rust and other dirt, the depth of the anchor reaches 40~100μm fully meet the adhesion requirements of anti-corrosion layer and steel pipe, while the spraying (throwing) of the rust removal process can be lower operating costs and stable and reliable quality to achieve near-white (Sa2.5 technical conditions.

  When the longitudinal welded pipe has a certain rust, according to a certain degree of derusting and methods of treatment, to ensure the quality and performance of longitudinal welded pipe, can be used in different industries and fields, for the construction industry to make important contributions and role.

  Spray (cast) abrasive for straight seam welded pipe: In order to achieve the ideal derusting effect, according to the surface hardness of the longitudinal welded pipe equipment, the original rust level, the required surface roughness, coating type, etc. to select the abrasive, for Single-layer epoxy, two or three-layer polyethylene coating, steel sand and steel balls of the mixed abrasive more easily achieve the ideal derusting effect. The steel pill has the function of strengthening the steel surface, while the steel sand has the function of etching the steel surface.

  Steel sand and steel balls of the mixed abrasive (usually steel pill hardness of 4050HRC steel sand hardness of 5060HRC can be used for various steel surface, even for the C-Class and D-class rust on the surface of steel, derusting effect is also very good.

  Derusting speed of straight seam welded pipe: That is, the total kinetic energy of the abrasive applied to the steel tube per unit time and the kinetic energy of the E1 steel pipe are determined by the type of abrasive and the displacement of the abrasive. Type medium: M abrasive spray (throw) quantity; v abrasive running speed; M1 single particle abrasive quality. The size of M is related to the abrasive crushing rate, and the crushing rate directly affects the interest of the surface disposal operation and the cost of derusting equipment.

  When the device is fixed, M is constant, Y is constant, so e is also a constant, but because the abrasive is broken, the M1 change, so it is generally necessary to choose the abrasive with lower loss rate, which is helpful to improve the cleaning speed and long blade life.

  The size and proportion of the abrasive of the longitudinal welded pipe: In order to obtain a better uniformity of cleanliness and roughness distribution, the particle size and proportion design of abrasive is very important.

  The roughness is too large to cause the anticorrosion layer to become thinner at the anchor Peak, and because of the too deep of the anchor pattern, the anticorrosion layer in the anti-corrosion process is easy to form a bubble, which seriously affects the performance of the anticorrosion layer. Can not only rely on large particles of high strength impact, roughness is too small will lead to anti-corrosion coating adhesion and impact strength decreased. For severe internal pitting. Also need to rely on small particles polished off corrosion products to achieve clean-up effect, at the same time reasonable ratio design can not only slow down the abrasive on the pipe and nozzle (blade) wear, and abrasive utilization can also be greatly improved. In general, the size of the steel pellets is 0.81.3mm steel grit diameter of 0.41.0mm of which the main components of 0.51.0mm. Sand pill ratio Generally 58 should be noted in the actual operation, the abrasive steel sand and the ideal ratio of steel balls is difficult to achieve the reason is hard and brittle steel sand than steel pill crushing rate is high. To this end, the operation should be sampled from sampling to test the mix of abrasive, according to the distribution of particle size, to rust machine into the new abrasive, and the new abrasive, the number of steel sand to occupy the main.