1, corrosion-resistant. Polyethylene is an inert material that, in addition to a few strong oxidizers, can withstand the erosion of various chemical media.

Spiral pipe is strip by roller, spiral spiral direction, and then through the capacitor for double submerged arc welding. Spiral welded pipe production process, prone to welding and missed welding many wrong edges and so on. However, under these conditions, trachoma is the most difficult to handle spiral steel butt weld.

Spiral submerged arc welded pipe production, forming and welding are carried out at the same time, so the stability of welding quality is good or bad, forming an indivisible. Forming tight when tight loose, "pouting", loose within the loose tight loose within the local error from the side shift, squeeze thick side panels, missing cutting, waves, burrs and conical irregular pores, resulting in poor and Weld undercut, burning, porosity, slag and other defects form. Therefore, we found that we must adjust the forming instability in time.

*Project:Spain Natural Gas Pipeline Project *Product Name:EWR/SSAW *Specification:GR.B; 48” *Quantity:600MT *Year:2015 *Country: Spain *Application:Gas transmission

Spiral pipe factory should be carried out before the mechanical properties test and flattening test, and the flaring test, to meet the standards. Straight seam steel quality inspection methods are as follows: 1, on the surface, that is visual inspection. Visual inspection of welded joints is a straightforward process, but widely used test methods are an important part of product testing with major defects and variations on the surface of the welded dimension. Usually with the naked eye, using standard models, gauges and test tools, such as magnifying glass. If the weld surface defects, weld defects may exist inside.

(1) Pipeline peak load demand due to the user's natural gas consumption is very uneven, frequent pipeline pressure fluctuations, alternating stress steel to withstand large pipe will expand the defects in alternating stress, if there is more choice , The probability of welding defects high, spiral welded pipe, the safe operation of the pipeline will not be guaranteed.

The advantage of a compact spiral pipe is that only a thin layer of side melts, which allows the extrusion of oxides and impurities to provide a pure, high quality weld. Side-by-side, spiral tube manufacturer oxide can be squeezed along two deflections.

Spiral stacking is conducive to the protection of the quality of the spiral steel pipe to extend the service life of spiral steel pipe to prevent deformation, erosion, spiral pipe orderly piled up, but also conducive to the latter spiral pipe loading, inventory. Spiral pipe buyers should also be strictly in accordance with the requirements of spiral steel pipe pile.

Spiral Pipe Production Test Process Analysis

Spiral pipe welding head

Spiral common defect detection method

Spiral steel pipe anti-corrosion measures and procedures are as follows: Fluid spiral corrosion requirements are different from other domestic projects, the main difference is:

Spiral broken steel and metal materials according to the material is basically the same divided into three types, damage: ① cleavage fracture, ② tie cave animals anti-fracture, ③ slip surface fracture separation.

Spiral steel pipe into the steel unit, multi-roll rolling strip gradually rolled up, and the formation of a gap with the open tube, squeeze roll to reduce the adjustment, weld gap control in 1 ~ 3mm, the weld flat.

Spiral steel pipe into the steel unit, multi-roll rolling strip gradually rolled up, and the formation of a gap with the open tube, squeeze roll to reduce the adjustment, weld gap control in 1 ~ 3mm, the weld flat. 1. If the gap is too large, resulting in reduced proximity effect, lack of eddy current, poor weld crystallization, indirect fusion or cracking bad. 2. The gap is too small, resulting in increased proximity effect, excessive welding heat, causing the weld to rupture; weld or extrusion, the formation of pit after rolling, affecting the weld surface quality.

Magnetic particle inspection or penetration testing can effectively detect surface cracks, folds, serious leather surface defects, hair lines, pinholes. For ferromagnetic materials, magnetic particle inspection method with high sensitivity, priority should be given to magnetic particle inspection; for non-ferromagnetic materials, such as stainless steel seamless pipe, penetrant flaw detection method.

Deformed mold complex is often complicated, but as long as we grasp the deformation laws, analyze the causes, the use of different prevention methods is to reduce the deformation of the mold, and can control it. In general, precision mold hot deformation can be taken in the following ways to prevent.

Squeeze forging, rolling method is the difference: 1, precision seamless extrusion heating temperature than forging, rolling high 30-60 ℃; 2, deformation, high-speed (rebar, only 2-4s). 3, multi-step, high consumption of meta

Squeeze forging, rolling method is the difference: 1, precision seamless extrusion heating temperature than forging, rolling high 30-60 ℃; 2, deformation, high-speed (rebar, only 2-4s). 3, multi-step, high metal consumption.

Precision light pipe passivation pickling, degreasing, ordinary precision three light tube surface treatment process.

Deformed mold complex is often complicated, but as long as we grasp the deformation laws, analyze the causes, the use of different prevention methods is to reduce the deformation of the mold, and can control it. In general, precision mold hot deformation can be taken in the following ways to prevent.