The welding procedure for the submerged arc welding straight seam steel pipe may be the submerged arc welding technology, which utilizes filler welding and particle protection flux submerged arc. The caliber created can achieve 1500mm. LSAW may be the abbreviation of submerged arc welded longitudinal seam steel pipe. The development procedure for LSAW steel pipe includes JCOE developing technology and coil developing submerged arc welding technology.

Once the caliber is big, two steel plates can be used as moving, that will form a dual weld phenomenon.

The pores from the LSAW steel pipe welds not just modify the tightness from the pipeline welds and cause pipeline leakage, but additionally become corrosion-inducing points, seriously lowering the weld strength and toughness. The standards that create pores within the weld are:

1. Flux composition. When welding includes a proper quantity of CaF2 and SiO2, it’ll react and absorb a lot of H2, and generate HF that’s highly stable and insoluble in liquid metal, therefore stopping the development of hydrogen pores.

2. The majority thickness from the flux is usually 25-45mm. The majority thickness from the flux is big and also the density is small, and also the bulk thickness is taken, and the other way around the majority thickness from the high current and occasional welding speed is taken the large value, and the other way around. Or once the air humidity is high, the recycled flux ought to be dried before use.

3. Surface management of steel plate. To avoid sundries for example iron oxide scale falling from uncoiling and leveling from entering the developing process, a surface cleaning device ought to be installed.

4. Steel plate edge treatment. The advantage from the steel plate ought to be outfitted with rust and burr removal devices to lessen the potential of pores. The positioning of the cleaning system is well installed following the edge milling machine and also the disc cutter. The dwelling from the system is two active steel wire wheels with adjustable clearance within the lower and upper positions somewhere, and also the board edge is pressed up and lower.

5. Weld shape. The developing coefficient from the weld is simply too small, the form from the weld is narrow and deep, the gas and inclusions are challenging float, and you can easily form pores and slag inclusions. Generally, the weld developing coefficient is controlled at 1.3-1.5, with thick-wall welded steel pipes using the bigger value, and thin-walling the smaller sized value.

6. Lessen the secondary magnetic field. To be able to lessen the influence of magnetic bias, the bond position from the welding cable around the work surface must only be far from the welding terminal to prevent area of the welding cable from establishing a secondary magnetic field around the work surface.

7. Process. The welding speed ought to be appropriately reduced or even the current ought to be elevated to obstruct the crystallization speed from the weld pool metal to facilitate gas escape. Simultaneously, when the delivery position from the strip is unstable, it ought to be adjusted over time to avoid frequent fine-tuning from the front axle or rear axle. The bridge maintains its shape, which makes it hard for gas to flee.

Tips:ASTM A53 covers seamless and welded steel pipe with nominal wall thickness. The top condition is generally black and hot-dipped galvanized. ASTM A 53 is created mainly for pressure and mechanical applications, and it is employed for transport of steam, water, gas line pipes.

ASTM A53 Grade B may be the material underneath the American steel pipe standard, API 5L Gr.B can also be the American standard materialFree Content , A53 GR.B ERW refers back to the electric resistance welded steel pipe of A53 GR.B API 5L GR.B Welded refers back to the material Welded steel pipe of API 5L GR.B.