ASTM A672 CC70 CS EFW Pipes description
In ASTM A672 C70 welded pipe, "C70" indicates a minimum yield strength of 70 ksi (approximately 483 MPa). This type of steel pipe possesses excellent mechanical properties and high-temperature resistance, meeting the stringent requirements of high-pressure piping systems. According to the ASTM A672 standard, this type of steel pipe must be manufactured using electric welding, and the weld seams must undergo non-destructive testing (such as ultrasonic or radiographic testing) to ensure their integrity. Furthermore, the chemical composition of the steel pipe must be strictly controlled, with a carbon content typically not exceeding 0.25%, and containing appropriate amounts of manganese, silicon, and other elements to enhance strength and toughness.
Carbon Steel ASTM A672 gr c70 Chemical Composition
| A672 Grades | Chemical composition | |||||
| C | Si | Mn | P | S | Ti | |
| CC70 / C70 | 0.27 | 0.13 ~0.45 |
0.79 ~1.30 |
0.035 | 0.035 | - |
Low CS ASTM A672 gr c70 Pipes Mechanical Properties Chart
| A672 Grades | Yield Strength (N/mm2) | Tensile Properties (N/mm2) | Elongation (%) | Welding point tensile strength (N/mm2) |
|---|---|---|---|---|
| CC70 / C70 | 260 | 485~620 | 21 | 485~620 |
The production of ASTM A672 CC70 welded pipe mainly includes the following key steps:
1. Sheet Preparation: Carbon manganese steel plates meeting standard requirements are selected and pre-treated (leveling, edge trimming, etc.) before entering the forming process.
2. Forming and Welding: The steel plates are bent into tubular shapes using JCOE or UOE forming processes, followed by straight seam welding using high-frequency welding (HFW) or submerged arc welding (SAW). Strict control of heat input is required during welding to avoid grain coarsening in the weld area.
3. Heat Treatment: Post-weld normalizing treatment is necessary to eliminate residual welding stress, homogenize the microstructure, and ensure that mechanical properties meet standards.
4. Inspection and Acceptance: Finished products undergo hydrostatic testing, non-destructive testing, and dimensional inspection. They are only released after meeting ASTM A672 and the customer's technical agreement.
Test and inspection
Packaging and shipping
