SSAW Pipe

What is SSAW steel pipe?

SSAW steel pipe, also known as spiral submerged arc welded steel pipe, is a spiral welded steel pipe produced by double-sided submerged arc welding. Spiral welded pipes are formed using narrower sheets or hot rolled coils, which greatly reduces their production costs. The spiral welding process allows the production of large diameter pipes suitable for transporting large quantities of oil and gas.

Surface: Lightly oiled, Hot dip galvanized, Electro galvanized, Black, Bare, Varnish coating/Antirust oil, Protective Coatings (Coal Tar Epoxy; Fusion Bond Epoxy, 3-layers PE)

Standard

SSAW mill line used for making Grade A, B, ～X70 steel coil with thickness 5.0mm to 25.4mm, width 400mm to 2000 mm into Spiral welding pipe with outer diameter from 219 mm to 3020mm through uncoiling, leveling, edge milling, forming and welding. The processing can satisfy producing spiral pipes according to standard API-5L, ASTM A53，GB/T9711-2011.

Chemical Analysis and Mechanical Properties of SSAW Steel Pipe

Coating Standard:

• ANSI/AWWA C104/A21.4 American National Standard for Cement-Mortar Lining for ductile-iron Pipe and Fittings for water
• DIN 30670 Polyethylene coatings of steel and fittings

Packing:  Plastic plugs in both ends, Hexagonal bundles of max. 2,000kg with several steel strips, Two tags on each bundle, Wrapped in waterproof paper, PVC sleeve, and sackcloth with several steel strips, Plastic caps.

SSAW is not stocked rather can easily be sourced for projects across the below range

Note:

Pipes can be sourced conforming to AS/NZS3678 Grade 350 L0 & manufactured to AS/NZS1163 tolerances & to grade C350 L0.

Pipes/piles can be sourced at longer lengths or with piling shoes spliced/welded to AS1554.1.

Spiral Submerged-arc Welded steel pipe technological process

Spiral welded pipe production by submerged arc method is based on using tandem welding technique for joining inside and outside coil edges, which have been trimmed and beveled by carbide milling for high quality weld structure.

Thermatool designs and manufactures Spiral Seam Annealing systems for producers of SAW (submerged arc welded) API line pipe.

Offering all the basic features and benefits of Thermatool seam annealing systems designed for operation on longitudinally welded API pipe, Thermatool Spiral Seam Annealing systems, however, require the installation of specially “shaped” inductors.

These are custom designed on CAD systems in order to precisely follow the helix angle for a specific pipe diameter.

There are nine modernized product lines in our company with the yield capacity of 1000 thousands tons of B-X80 steel pipe of φ219-φ3200mm, WT5-30mm.

Listing some notes You must know

• Oiled marking: Steel after passing wrer oiled to prevent corrosion,and according to user requirements for making.
• Leveling Milling: The flat steel anvil machine so that the origal curl,and then thouth the edge milling machine for two-sided steel milling,so as to meet the requirements of the plate width,plate edge parallelism and groove shape.
• Shear molding: The steel plate production line along the outer edge of the spiral curl into a tube.
• Butt cut: Double-sided submerged arc welding using advanced technology to pre-welding,internal welding,outside wilding.The welded steel pipe using a plasma-foot cut to specification length.

Spiral steel pipe manufacturing process

Spiral steel pipe (SSAW/ SAWH) is also called spiral welded pipe. It is made by rolling a low-carbon structural steel or low-alloy structural steel strip at a certain helical angle (called a forming angle) into a tube blank, and then welding the tube seams. It can be produced with narrower strip steel. Large diameter steel pipe.

The manufacturing process of the spiral steel tube (SSAW):

1. The raw materials are strip coil, welding wire and flux. They must undergo strict physical and chemical inspections before being put into use.
2. The head and tail of the strip are butted by single wire or double wire submerged arc welding, and automatic submerged arc welding is used for repair welding after rolling into a steel pipe.
3. Before forming, the strip is leveled, trimmed, planed, surface cleaned and conveyed and pre-bending.
4. The electric contact pressure gauge is used to control the pressure of the cylinder on both sides of the conveyor to ensure the smooth conveying of the strip.
5. Adopt external control or internal control roll forming.
6. The weld gap control device is used to ensure that the weld gap meets the welding requirements, and the pipe diameter, the amount of misalignment and the weld gap are strictly controlled.
7. Both internal welding and external welding use the American Lincoln welding machine for single wire or double wire submerged arc welding, so as to obtain stable welding specifications.
8. The welded seams are all inspected by an online continuous ultrasonic automatic flaw tester, which ensures 100% non-destructive testing coverage of the spiral welds. If there is a defect, it will automatically alarm and spray the mark, and the production workers can adjust the process parameters at any time accordingly to eliminate the defect in time.
9. Use an air plasma cutting machine to cut the steel pipe into single pieces.
10. After cutting into a single steel pipe, each batch of steel pipes must undergo a strict first inspection system to check the mechanical properties, chemical composition, fusion condition of the weld, the surface quality of the steel pipe and non-destructive testing to ensure that the pipe making process is qualified. Only then can it be officially put into production.
11. The parts with continuous sonic flaw detection marks on the welds shall be re-examined by manual ultrasonic wave and X-ray. If they are indeed defective, they shall be repaired and subjected to non-destructive inspection again until it is confirmed that the defects have been eliminated.
12. The tube where the strip butt welding seam and the T-joint intersecting with the spiral welding seam are located shall all be inspected by X-ray television or filming.
13. Each steel pipe is tested by hydrostatic pressure, and the pressure is radially sealed. The test pressure and time are strictly controlled by the water pressure microcomputer detection device of the steel pipe. The test parameters are automatically printed and recorded.
14. The pipe end is machined so that the verticality of the end face, the bevel angle and the blunt edge are accurately controlled.