| 1 | Manufacturer Profile A | ERW water pipe Structural tube Galvanized pipe | High-frequency electric resistance welding with automatic sizing and straightening. | Outside diameter commonly from 21.3 mm to 630 mm; wall thickness selected according to diameter and grade. | GB/T 3091 GB/T 6725 ASTM A53 | Plain ends, beveled ends, threaded ends, hot-dip galvanized surfaces, and black painted surfaces. | Chemical analysis, tensile testing, bend testing, hydrostatic testing, dimensional inspection, and visual examination. | Water transmission, fire-protection systems, scaffolding, construction, and general fabrication. |
| 2 | Manufacturer Profile B | Large-diameter SSAW pipe Water pipeline pipe Structural pipe | Spiral submerged arc welding using formed steel strip and internal and external weld passes. | Commonly produced from approximately 219 mm to 3,500 mm outside diameter. | GB/T 9711 GB/T 3091 API 5L | Plain or beveled ends; liquid epoxy, fusion-bonded epoxy, 3PE, and cement-mortar lining may be specified. | Hydrostatic testing, weld inspection, ultrasonic testing, radiographic testing when specified, and coating inspection. | Municipal water, long-distance water transfer, piling, dredging, and low-pressure fluid service. |
| 3 | Manufacturer Profile C | Seamless carbon steel pipe Boiler tube Mechanical tube | Hot piercing, rotary rolling, heat treatment, sizing, straightening, and cutting. | Typical outside diameter range from about 25 mm to 660 mm, depending on equipment and grade. | GB/T 8162 GB/T 8163 ASTM A106 ASTM A179 | Plain ends, beveled ends, capped ends, black varnish, oil coating, and temporary corrosion protection. | Tensile, flattening, flaring, hydrostatic, hardness, ultrasonic, and dimensional tests as required. | Machinery, pressure piping, heat exchangers, boilers, and petroleum-processing equipment. |
| 4 | Manufacturer Profile D | API line pipe ERW line pipe LSAW pipe | Longitudinal submerged arc welding or high-frequency welding with controlled forming and weld monitoring. | ERW sizes commonly cover approximately 114.3–610 mm; LSAW sizes may extend beyond 1,000 mm. | API 5L ISO 3183 GB/T 9711 | Beveled ends, internal and external coating systems, 3PE, FBE, and bare pipe supply. | Hydrostatic testing, weld ultrasonic testing, radiographic testing where specified, tensile testing, impact testing, and coating checks. | Oil and gas gathering, water transmission, industrial fluid pipelines, and energy infrastructure. |
| 5 | Manufacturer Profile E | Square hollow section Rectangular hollow section Circular hollow section | Cold-forming of hot-rolled strip followed by high-frequency welding and precision sizing. | Common structural sections range from approximately 20 × 20 mm to 500 × 500 mm; larger sizes are project-dependent. | GB/T 6725 GB/T 6728 ASTM A500 | Plain ends, cut-to-length, galvanized, powder-coated, or primer-coated finishes. | Tensile testing, corner and weld inspection, dimensional checks, flattening testing, and coating-thickness inspection. | Steel structures, warehouses, bridges, mechanical frames, solar supports, and architectural fabrication. |
| 6 | Manufacturer Profile F | Hot-dip galvanized pipe Scaffold tube Conduit pipe | ERW tube production followed by zinc pretreatment, hot-dip galvanizing, cooling, and passivation. | Commonly supplied in nominal sizes from 15A to 300A, with thickness selected for service requirements. | GB/T 3091 ASTM A53 EN 10255 | Uniform zinc coating, threaded and coupled ends, grooved ends, plain ends, and protective caps. | Zinc-coating thickness, coating adhesion, hydrostatic or air-pressure testing, thread inspection, and dimensional checks. | Water supply, scaffolding, handrails, agricultural structures, fire protection, and outdoor construction. |
| 7 | Manufacturer Profile G | Precision welded tube Cold-drawn tube Automotive tube | Cold drawing or cold rolling after welding, with bright annealing and high-accuracy sizing where required. | Typical precision products range from approximately 6 mm to 168 mm outside diameter. | GB/T 3639 EN 10305 ASTM A513 | Bright annealed, oiled, phosphated, zinc-coated, or supplied with a controlled surface finish. | Dimensional measurement, surface roughness, hardness, eddy-current testing, tensile testing, and leak testing. | Automotive components, hydraulic cylinders, furniture, machinery, and precision engineering. |
| 8 | Manufacturer Profile H | LSAW pipe JCOE pipe Heavy-wall structural pipe | Plate forming by progressive JCOE or UOE methods, followed by internal and external submerged arc welding. | Commonly manufactured from about 406 mm to 1,422 mm outside diameter, with heavy wall options available. | API 5L ISO 3183 GB/T 9711 | Beveled ends, internal and external coatings, 3PE, FBE, epoxy, or bare steel finish. | 100% weld ultrasonic testing, radiographic testing when specified, hydrostatic testing, tensile testing, impact testing, and dimensional inspection. | Transmission pipelines, offshore structures, bridge piles, large water mains, and industrial infrastructure. |
| 9 | Manufacturer Profile I | Spiral welded pipe Piling pipe Slurry pipeline pipe | Continuous spiral forming and submerged arc welding with automated seam tracking. | Typical outside diameters range from approximately 219 mm to 2,540 mm, depending on plate width and mill design. | SY/T 5037 GB/T 3091 ASTM A252 | Plain or beveled ends, external epoxy, 3PE coating, cement-mortar lining, or project-specific protection. | Hydrostatic testing, weld inspection, ultrasonic or radiographic examination, dimensional checks, and coating inspection. | Foundation piles, slurry transport, dredging, waterworks, ports, and large-diameter low-pressure pipelines. |
| 10 | Manufacturer Profile J | Galvanized structural tube Solar mounting tube Greenhouse tube | High-frequency welded tube production with roll forming, cut-to-length processing, and zinc protection. | Commonly supplied from approximately 20 mm to 219 mm outside diameter, including square and rectangular sections. | GB/T 6725 GB/T 3091 ASTM A500 ASTM A53 | Hot-dip galvanized, pre-galvanized, zinc-aluminum coated, powder-coated, or black painted surfaces. | Tensile testing, weld integrity inspection, zinc-coating measurement, dimensional inspection, and salt-spray testing when specified. | Solar mounting systems, greenhouses, fencing, agricultural buildings, light steel structures, and outdoor frames. |