Spiral welded pipe is frankly also a spiral steel pipe is called, generally refers to the diameter of more than 1 meter spiral steel pipe. Steel pipe should be hydrostatic, bending, flattening and other experiments, the surface quality has certain requirements, usually delivery length of 12 meters, often require fixed-foot delivery.
1, yield point With the yield phenomenon of metal materials, the specimen in the tensile process force does not increase (keep constant) can still continue to elongate when the stress, called the yield point. If the force decreases, then the upper and lower yield point should be distinguished. The unit of yield point is N/mm2 (MPa).
2, tensile strength specimen in tension, the maximum force sustained in tension (Fb), out of the original cross-sectional area of the specimen (So) obtained stress (σ), known as tensile strength (σb), the unit is N/mm2 (MPa). It indicates the maximum ability of a metallic material to resist damage under tension.
3, elongation at break In a tensile test, the percentage increase in the length of the specimen's marking distance from the original marking distance after the specimen is pulled off is called the elongation rate. Expressed as σ in %.
Spiral seam high-frequency welded steel pipe for general low-pressure fluid transportation (SY5039-83) is made of hot rolled steel strip coil as pipe billet, formed by frequent temperature spiral forming, and welded by high-frequency lap welding method for general low-pressure fluid transportation with spiral seam high-frequency welded steel pipe. Spiral welded steel pipe for piling (SY5040-83) is made of hot rolled steel strip coil as billet, regular temperature spiral molding, double-sided submerged arc welding or high-frequency welding, used for civil engineering structures, docks, bridges and other foundation piles with steel pipe.
Spiral steel pipe is a strip steel coil as raw material, regular temperature extrusion molding, automatic double-wire double-sided submerged arc welding process welded spiral seam steel pipe. Spiral steel pipe strength is generally higher than the straight seam welded pipe, can use a narrower billet to produce a larger diameter welded pipe, but also can use the same width of the billet to produce a different diameter welded pipe.
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