SSAW STEEL PIPES

Spiral steel pipe (SSAW), Spiral welded pipe, SAWL steel pipe, Spiral submerged arc pipe, Spiral welded steel pipe

SSAW Steel PipeSpiral steel pipe, also known as spiral welded pipe, is made by rolling low-carbon structural steel or low-alloy structural steel strip into a tube blank at a certain spiral angle (called forming angle), and then welding the tube seams. It can produce large-diameter steel pipes with narrower strip steel.

Features:
The production process of straight seam welded pipe (ERW/LSAW) is simple, with high production efficiency, low cost and rapid development. The strength of spiral welded pipe is generally higher than that of straight seam welded pipe. It can produce welded pipes with larger diameters with narrower billets, and can also produce welded pipes with different diameters with billets of the same width. However, compared with straight seam pipes of the same length, the weld length increases by 30~100%, and the production speed is lower. Therefore, most smaller diameter welded pipes use straight seam welding, while large diameter welded pipes mostly use spiral welding.

Standard & Class

Classfication
Standard
Main Products
Steel Pipe for Fluid Service
GB/T 14291
Welded pipe for mine fluid sevice
GB/T 3091
Welded pipe for low pressure fluid service
SY/T 5037
Spirally submerged arc welded steel pipe for pipelines for low pressure fluid service
ASTM A53
Black and hot-hipped galvanized welded and seamless steel pipe
BS EN10217-2
Welded steel tybes for pressure purposes - delivery technical conditions - part2: Electric welded non- alloy and alloy steel tubes with specified elevated temperature properties
BS EN10217-5
Welded steel tybes for pressure purposes - delivery technical conditions - part5: submerged arc welded non-alloy and alloy steel tubes with specified elevated temperature properties
Steel Pipe for Ordinary Structure
GB/T 13793
Longitudinally electric resistance welded steel pipe
SY/T 5040
Spirally submerged arc welded steel pipe piles
ASTM A252
Welded and seamless steel pipe piles
BS EN10219-1
Cold formed welded structural hollow sections of non-alloy and fine grain steels - part1: Technical delivert conditions
BS EN10219-2
Cold formed welded structural hollow sections of non-alloy and fine grain steels - part2: tolerances dimmsions and sectional properties
Line Pipe
GB/T 9711.1
Steel pipe for pipeline transportation system of petroleum and natural gas industries(Class A steel pipe)
GB/T 9711.2
Steel pipe for pipeline transportation system of petroleum and natural gas industries(Class B steel pipe)
API 5L PSL1/2
Line pipe
Casing
API 5CT/ ISO 11960 PSL1
Steel pipe for use as casing or tubing for wells of petroleum and natural gas industries

SSAW steel pipe is the raw material of strip coil, often temperature extrusion molding, automatic double-wire double submerged arc welding process made of spiral seam pipe. Spiral steel pipe will strip into the pipe unit, the multi-roll rolling, strip rolled up, forming a circular gap opening gap, adjust the squeeze roll reduction, the weld gap control in the 1 ~ 3mm, and make both ends of the weld flush.

(1) Raw materials are strip steel coil, welding wire and flux. They must undergo strict physical and chemical inspection before being put into use.
(2) The head and tail of the strip steel are butt-jointed by single-wire or double-wire submerged arc welding. After being rolled into a steel pipe, automatic submerged arc welding is used for repair welding.
(3) Before forming, the strip steel is leveled, trimmed, planed, surface cleaned, conveyed and pre-bent.
(4) An electric contact pressure gauge is used to control the pressure of the oil cylinder on both sides of the conveyor to ensure the smooth conveying of the strip steel.
(5) Externally controlled or internally controlled roller forming is adopted.
(6) A weld gap control device is used to ensure that the weld gap meets the welding requirements. The pipe diameter, misalignment and weld gap are strictly controlled.
(7) Both internal and external welding are performed by single-wire or double-wire submerged arc welding using an American Lincoln electric welder to obtain stable welding specifications.
(8) All welds are inspected by online continuous ultrasonic automatic flaw detectors to ensure 100% non-destructive testing coverage of spiral welds. If there are defects, an automatic alarm will be sounded and a mark will be sprayed. The production workers can adjust the process parameters at any time to eliminate the defects in time.
(9) The steel pipes are cut into single pieces by an air plasma cutting machine.
(10) After cutting into single steel pipes, each batch of steel pipes must undergo a strict first inspection system to check the mechanical properties, chemical composition, fusion status, surface quality of the welds and non-destructive testing to ensure that the pipe making process is qualified before it can be officially put into production.
(11) The parts with continuous ultrasonic flaw detection marks on the welds are re-inspected by manual ultrasonic and X-ray. If there are defects, they are repaired and then subjected to non-destructive testing again until it is confirmed that the defects have been eliminated.
(12) The butt welds of the strip steel and the pipes where the T-joints intersect with the spiral welds are all inspected by X-ray television or film.
(13) Each steel pipe is subjected to a hydrostatic test, and the pressure is radially sealed. The test pressure and time are strictly controlled by a steel pipe water pressure microcomputer detection device. The test parameters are automatically printed and recorded.
(14) The pipe end is machined to accurately control the end face verticality, groove angle and blunt edge.