Spiral pipe, also known as spiral steel pipe or spiral welded pipe, is a low carbon structural steel or low alloy structural steel strip coiled into billet according to a certain spiral angle (called forming angle), and then welded pipe seam. It can produce large diameter steel pipe with narrow strip.
Relevant introduction of spiral tube biology:
The outer diameter of the helical tube is about 30 nanometers, the inner diameter is about 10 nanometers, and the distance between adjacent helixes is about 11 nanometers. The helical tube is surrounded by six nucleosomes every week. H1 histone is located on the inner surface of the helical lumen and plays an important role in maintaining the helical tube structure.
Let's look at the scope of the helical tube.
Spiral pipes are mainly used for oil and natural gas pipelines, and their specifications are expressed by external diameter * wall thickness. It is suitable for steel pipes for water, sewage, air, heating steam and flammable fluids and other common low-pressure fluid pipelines. It is also suitable for other fluid pipelines with similar requirements.
現在螺旋管的常用標準一般分為:SY/T5037-2000（部標、也叫 普通流體輸送管道用螺旋縫埋弧焊鋼管）、GB/T9711.1-1997（國標、也叫石油天然氣工業輸送鋼管交貨技術條件第一部分：A級鋼管(到目前要求嚴格的有GB/T9711.2 B級鋼管)）、API-5L（美國石油協會、也叫管線鋼管；其中分為PSL1和PSL2兩個級別）、SY/T5040-92（樁用螺旋縫埋弧焊鋼管）。
At present, the commonly used standards of spiral pipe are generally divided into: SY/T5037-2000 (ministerial standard, also known as spiral submerged arc welded steel pipe for ordinary fluid transmission pipeline), GB/T9711.1-1997 (national standard, also known as technical conditions for delivery of oil and gas industry pipeline Part I: A-grade steel pipe (up to the present strict requirements are GB/T9711.2 B-grade steel pipe), AP. I-5L (American Petroleum Association, also known as pipeline steel pipe; which is divided into two levels of PSL1 and PSL2), SY/T5040-92 (spiral submerged arc welded pipe for piles).
Commonly used spiral tube materials in China are: Q235A, Q235B, Q345, L245, L290, X42, X52, X60, X70, X80, 0Cr13, 1Cr17, 00Cr19Ni11, 1Cr18Ni9, 0Cr18Ni11Nb.