we have obtained ISO 9001, ISO 14001, ISO 45001, CE, AAA-level credit rating certification, etc.
 
we have obtained ISO 9001, ISO 14001, ISO 45001, CE, AAA-level credit rating certification, etc.
 
ASTM a178 / a178M Standard Specification for Electric-Resistance-Welded Carbon Steel and Carbon-Manganese Steel Boiler and Superheater Tubes. ASTM a178 standard refers to electric-resistance-welded tubes with minimum-wall-thickness. Materials are carbon steel and carbon-manganese steel, ASTM a178 pipe and tube is to be used in boiler tubes, boiler flues, superheater flues and safe ends.
Outside diameter and Wall thickness tolerance
| Outside Diameter tolerance | Wall thickness tolerance | ||
| OD < 50 | ±0.05mm | S < 4mm | ±12.5% | 
| OD > 50 | ±1% | 4--20mm | -120 | 
| 
 | 
 | S≧20mm | ±12.5% | 
Chemical Requirements
| Element | Grade A | Grade C | Grade D | 
| % | Low carbon steel | Medium Carbon Steel | Manganess Steel | 
| C | 0.06-0.18 | 0.35 Max | 0.27 Max | 
| Mn | 0.27-0.63 | 0.80 Max | 1.00-1.50 | 
| P | 0.035 | 0.035 | 0.03 | 
| S | 0.035 | 0.035 | 0.015 | 
| Si | ... | ... | 0.10 Min. | 
Tensile Requirements
Grade C and D tubes shall conform to the requirements as to tensile properties
| Data | GradeC | GradeD | 
| Tensilestrength,min,ksi[MPa] | 60[415] | 70[485] | 
| Yieldstrength,min,ksi[MPa] | 37[255] | 40[275] | 
| Elongationin2in.or50mm,min,% | 30 | 30 | 
| For longitudinal strip tests a deduction for Each1⁄32-in[0.8mm]decreaseinwallthicknessbelow5⁄16in.[8mm] | 1.50A | 1.50A | 
The actual mean wall is defined as the average of the thickest and thinnest wall in that section.
Welded tubes 65 %
| Type | Over | Under | 
| Welded Tubes | 0.18 | 0 | 
Mechanical Property:
Grade C & Grade D tubes shall conform to the requirements -tensile properties prescribed below:
| Type | Over | Under | 
| Welded Tubes | 0.18 | 0 | 
Application Industries
A178 Boiler Pipes & Tubes are used in boiler, superheater, heat-exchanger and pressure equipment in Petrochemical factory, Refinery factory, sugar mill, power plant, power plant, shipbuilding.Used in boiler, superheater, heat-exchanger and pressure equipment in Petrochemical factory, Refinery factory, sugar mill, power plant, power plant, shipbuilding.