ASTM A252 Welded&Seamless Carbon Steel Pipe description
Specification
Name: ASTM A252 Standard Specification for Welded and Seamless Steel Pipe Piles
Core Object: Straight seam submerged arc welded pipe (not applicable to spiral welded pipe)
Core Use: Manufacturing permanent load-bearing pile foundations (such as steel piles or concrete pile casings in building/bridge foundations)
Core Control Requirements
Material Grades
GR1 (Foundation Grade): Yield strength ≥ 205 MPa, for shallow pile foundations (≤ 20 meters)
GR2 (Mainstream Grade): Yield strength ≥ 290 MPa, suitable for pile depths ≤ 40 meters (accounting for 60%+ of global usage)
GR3 (High Strength Grade): Yield strength ≥ 345 MPa MPa, for super high-rise/cross-sea projects (>40m pile depth)
Mandatory Testing Items
Hydraulic Pressure Test: ≥5MPa pressure held for 5 seconds, no leakage (verifies sealing)
Flattening Test: When compressed to 1/3 of the pipe diameter, no weld cracking (critical failure threshold)
Bending Test: After 180° cold bending, no weld cracks ≥3mm (simulates construction stress)
Tensile Test: 2 samples per furnace batch, strength must meet the corresponding grade (e.g., GR2 tensile strength ≥415 MPa)
Dimensional Tolerances
Outer diameter error ≤±0.75%, wall thickness negative deviation >10% is rejected. Straightness ≤3mm/3m (prevents pile tilting)
Mechanical Properties
Chemical Structure of A252 Steel Piling Pipe
Elongation Values of A252 seamless Erw Pipes
Reference Standards For Making ASTM A252 PIPE
ASTM A370 inspection methods and definitions for mechanical test of steel products.
ASTM A751: Chemical analyze test methods.
ASTM A941: Terminology for carbon, alloy and stainless steel.
E29 practice for to use significant digits in test result to decide the conformance with specification.
ASTM A252 Standard Inspection Items & Requirements
| Inspection Category | Test Item | Standard Requirement | Engineering Significance |
|---|---|---|---|
| Hydrostatic Test | Test Pressure | ≥5 MPa held for ≥5 seconds | Sealing integrity verification |
| Acceptance Criteria | No leakage/permanent deformation | ||
| Flattening Test | Compression Level | Compressed until distance between plates = 1/3 × nominal pipe diameter | Weld toughness & bonding strength inspection |
| Acceptance Criteria | No cracking in weld zone (Immediate rejection if failed) |
||
| Bend Test | Bend Angle | 180° cold bend (Mandrel diameter = 0.75 × pipe diameter) |
Simulates construction stress |
| Acceptance Criteria | No cracks ≥3mm in weld | ||
| Tensile Test | Specimen Quantity | 2 specimens per heat lot | Material strength validation |
| Yield Strength | GR1≥205 MPa, GR2≥290 MPa, GR3≥345 MPa | ||
| Tensile Strength | GR1≥345 MPa, GR2≥415 MPa, GR3≥485 MPa | ||
| Dimensional Tolerance | Outer Diameter (OD) | ±0.75% | Ensures pile-soil interaction accuracy |
| Wall Thickness (WT) | ±10% (Reject if WT- < 90% nominal) |
||
| Straightness | ≤3mm per 3m length | Critical for pile driving verticality |
Packaging and shipping
