The process of Lsaw steel pipe:
Plate feeding → Edge Milling and Beveling → Board Probe → Edge Crimping →molding→Slag→Track Pre-Welding → Tab Welding → Inside Welding → Slag → Outside Welding → Tab Removal → Ultrasonic Inspection → X-ray Inspection → Mechanical Expansion → Flame Flat → Hydro-static Testing → Ultrasonic Inspection for pipe end and welding seam → Weld and Pipe End X-ray Inspection → Tube end weld grinding → End Facing and Beveling → Weighing and measuring → Spray paint Marking → Final Inspection → Storage → Storage and Shipment
A252 Comparitive Specifications
ASTM Specification A252 describes nominal (average) wall steel pipe piles of cylindrical shape and applies to pipe piles in which the steel cylinder acts as a permanent load-carrying member or as a shell to form case-in-place concrete piles.
Surface imperfections exceeding 25% of the nominal wall in depth are considered defects. Defects not exceeding 22.5% of the nominal wall in depth may be repaired by welding. Before welding, the defect shall be completely removed.
CHEMICAL REQUIREMENTS FOR A252
• Testing Requirements for seamless and welded A252 steel piling pipe
Plate feeding → Edge Milling and Beveling → Board Probe → Edge Crimping →molding→Slag→Track Pre-Welding → Tab Welding → Inside Welding → Slag → Outside Welding → Tab Removal → Ultrasonic Inspection → X-ray Inspection → Mechanical Expansion → Flame Flat → Hydro-static Testing → Ultrasonic Inspection for pipe end and welding seam → Weld and Pipe End X-ray Inspection → Tube end weld grinding → End Facing and Beveling → Weighing and measuring → Spray paint Marking → Final Inspection → Storage → Storage and Shipment
A252 Comparitive Specifications
ASTM Specification A252 describes nominal (average) wall steel pipe piles of cylindrical shape and applies to pipe piles in which the steel cylinder acts as a permanent load-carrying member or as a shell to form case-in-place concrete piles.
Surface imperfections exceeding 25% of the nominal wall in depth are considered defects. Defects not exceeding 22.5% of the nominal wall in depth may be repaired by welding. Before welding, the defect shall be completely removed.
MECHANICAL PROPERTIES – TENSILE REQUIREMENT
|
|
Grade 1 |
Grade 2 |
Grade 3 |
|
Tensile Strength, min, psi |
50,000 |
60,000 |
66,000 |
|
Yield Strength |
30,000 |
35,000 |
45,000 |
CHEMICAL REQUIREMENTS FOR A252
|
|
Phosphorus |
|
Seamless and Welded |
Max% 0.050 |
• Testing Requirements for seamless and welded A252 steel piling pipe
- Hydrostatic Testing: Not specified.
- Mechanical Tests:
Tensile Test: Either longitudinal or transverse at option of manufacturer.
- Number of Tests: One tensile test per 200 lengths.
• Permissible Variations for A252 steel piling pipe
- Wall thickness: Not more than 12.5% under the nominal wall thickness specified.
- Weights per foot: The weight of any individual length of pipe shall not vary more than 15% over or 5% under the weight specified. Each individual length shall be weighed separately.
- Outside diameter: Shall not vary more than plus or minus 1% from the diameter specified.
• Lengths of A252 steel piling pipe
Steel Tubular Products A252 steel piling pipe may be ordered in single or double random lengths or in uniform lengths.
- Single random – 16’ – 25’ inclusive
- Double random – Over 25’ with a minimum average of 35’
- Uniform – Plus or minus 1” on length specified
• Marking Requirements
Rolled, die-stamped, or paint-stenciled (manufacturer’s option).
- Manufacturer’s name, brand, or trademark
- Heat number
- Method of pipe manufacture
- Size, weight, length
- Wall thickness
- ASTM A252 and steel grade
