Straight seam steel pipe is a kind of welded steel pipe. After forming a hot-rolled steel coil by a forming machine, the steel coil is transformed into a cylindrical shape. The high-frequency current skin effect and proximity effect or arc combustion under the flux layer are used for welding, so that the edge of the tube blank is heated and melted under a certain extrusion pressure and finally cooled and formed. Straight seam steel pipes can be divided into high-frequency straight seam steel pipes (ERW Pipe
) and submerged arc welded straight seam steel pipes (LSAW Pipe
) according to the production process. Petroleum, metallurgy, construction, coal, ports, machinery, etc. The industry is widely used in oil and gas transportation, low-pressure water gas transportation, mining fluid transportation, belt conveyors, automobile drive shafts and other industries.
Longitudinal welded pipe equipment plays an important role in people's life and work. But the maintenance of straight seam steel pipes has always been a headache. Let us understand the precautions in the maintenance process.
1). Choose a suitable location and warehouse
1. The place and warehouse where steel pipes are stored should be clean, free of water, and far away from factories and mines that produce harmful gases and dust. Weeds and debris should be removed on site to keep steel pipes clean.
2. Do not pile corrosive substances such as acid, alkali, salt, cement, etc. on the steel pipe in the warehouse. Different types of steel pipes should be stacked separately to prevent confusion and contact corrosion.
3. Large section steel, rails, faded steel plates, large diameter steel pipes, forgings, etc. can be stacked in the open air.
4. Small and medium-sized steel pipes, metal wires, steel wires, medium-diameter steel pipes, steel wires and wire ropes can be stored in a well-ventilated material shed, but underlays must be installed.
5. Some small steel pipes, steel strips, silicon steel plates, steel plates, small or thin-walled steel pipes, various types of cold-rolled and cold-drawn steel pipes, and high-priced and easily corrosive metal products can be stocked.
6. Choose a warehouse based on geographic location.
7. The warehouse should be ventilated on sunny days, and closed on cloudy and rainy days, and maintain a proper storage environment.
2). Reasonable stacking, first in first out
1. The principle of stacking is that under stable and safe stacking conditions, it should be stacked according to varieties and specifications, and different types of materials should be stacked separately to avoid confusion and mutual corrosion.
2. It is strictly forbidden to store articles corrosive to steel pipes near the stacking position.
3. The bottom of the pile should be high, strong and flat to prevent the material from being damp or deformed.
4. Similar materials are stacked in the order of storage, and the principle of first in, first out is realized.
5. For section steel stacked in the open, there must be wooden mats or stone bars underneath, the stacking surface should be slightly inclined to facilitate drainage, and attention should be paid to the flatness of the material to prevent bending and deformation.
6. The stack height for manual operation should not exceed 1.2m, the stack height for mechanical operation should not exceed 1.5m, and the stack width should not exceed 2.5m.
7. There should be a certain passage between the stacks, the width is usually 0.5 meters, and the approach road depends on the size of the materials and transportation machinery, usually 1.5-2 meters.
8. The bottom is raised, the warehouse is a cement floor, and the height is 0.1m; if it is muddy, it must be filled with 0.2-0.5m. If it is a wilderness, the cement floor is raised by 0.3-0.5m, and the sand and mud surface is raised by 0.5-0.7m.
9. The angle steel and channel steel in the open air environment should be bent downward, that is, the steel pipe should be downward and erect. The channel surface of the steel pipe should not face upward to prevent the accumulated water from rusting.
3). The packaging and protective layer of protective materials. The preservatives or other electroplating and packaging used by the steel plant before leaving the factory are important measures to prevent materials from rusting. During transportation and loading and unloading, care should be taken to protect them to extend the storage period of the materials.
4). Keep the warehouse clean and strengthen material maintenance
Mainly as follows:
1. Before entering the warehouse, care should be taken to prevent rainwater from getting wet or mixed with impurities, and use different methods to clean contaminated materials according to its performance. For example, available high-hardness steel wire brushes, cloth, cotton, etc.
2. The materials should be checked frequently after storage. If there is rust, please remove the rust layer.
3. After the surface of ordinary steel pipes are cleaned, no oil is required, but the inner and outer surfaces of high-quality steel pipes, alloy steel, thin-walled pipes, alloy steel pipes, etc. must be coated with anti-rust oil.
Through the above introduction, I believe everyone has a certain understanding and understanding of the precautions in the maintenance process of ERW straight seam steel pipe.
Tips: astm a53 grade b is more popular than other grades. These pipes can be bare pipes without any coating, or it may be Hot-Dipped or Zinc-Coated and manufactured by Welding or by a Seamless manufacturing process. In Oil and Gas, A53 grade pipes are used in the structural and non-critical applications.