SSAW Spiral Submerged Arc Welded Pipe High Compressive Strength And Long Service Life
SSAW Spiral submerged arc welded pipe, including ordinary spiral steel pipe and thick-walled spiral steel pipe. Thick-walled spiral steel pipe with respect to the general wall of the advantages of spiral steel pipe is: high compressive strength, high impact strength, high safety performance, longer service life. The The strength of the LSAW spiral welded pipe is generally higher than that of the straight seam welded pipe, and the pipe with larger diameter can be produced with the narrow billet. The same width of the blank can also produce different pipe sizes. LSAW spiral welded pipe nominal diameter, also known as the average diameter. This is the tube from the metal tube is thin, tube diameter and tube diameter is almost the same, so the outer diameter of the tube and the tube diameter of the average as the diameter of the call.
SSAW spiral welded pipe is a strip coil as raw material, often temperature extrusion molding, automatic double wire double-sided submerged arc welding process welded seam steel pipe.
1. The use of weld gap control device to ensure that the weld gap to meet the welding requirements, diameter, misalignment and weld gap are strictly controlled.
2. Strip head and tail docking, the use of single or double wire submerged arc welding, rolled into steel pipe after the use of automatic submerged arc welding.
3. Welded welds have been on-line continuous ultrasonic automatic injury inspection to ensure that the spiral weld nondestructive testing coverage. If there is a defect, automatic alarm and spray marking, production workers at any time to adjust the process parameters, the timely elimination of defects.
4. Before forming, the strip through the leveling, cutting edge, planing edge, surface cleaning and delivery to the edge of the treatment.
5. The use of electrical contact pressure gauge on both sides of the conveyor to control the pressure of the cylinder to ensure the smooth delivery of the strip.
6. Cut into a single steel pipe, each batch of steel pipe must be a strict first inspection system, check the weld mechanical properties, chemical composition, melting conditions, steel pipe surface quality and after nondestructive testing to ensure that the pipe after passing , In order to formally put into production.
7. Welds on the seam with continuous acoustic flaw marks, after manual ultrasonic and X-ray review, if there is a defect, after repair, again after the nondestructive test until the defect has been confirmed to eliminate.
Submerged arc welding (including buried arc surfacing and electroslag welding, etc.) is an important welding method, its inherent welding quality is stable, welding productivity is high, no arc and dust and so on, make it a pressure vessel, Pipe section manufacturing, box beam and other important steel structure in the production of the main welding methods. In recent years, although there have been many kinds of efficient, high-quality new welding methods, but the application of submerged arc welding is still not affected. From a variety of welding methods of the proportion of the proportion of deposited metal weight, submerged arc welding about 10%, and for many years has been little change. In the case of
When the welding wire is determined (usually depending on the welded steel), the matching flux becomes a key material, which directly affects the mechanical properties of the weld metal (especially plasticity and low temperature toughness), crack resistance, weld defect rate And welding productivity. The weight ratio of welding wire and flux is wire: flux = 1.1 ~ 1.6, depending on the type of welding joint, the type of flux used, welding specification parameters. Compared with the flux, the amount of sintered flux is more economical, about 20% less.