1.Raw Material Preparation & Inspection: Adopt qualified carbon steel, stainless steel and alloy steel pipes or bars conforming to ASTM and ASME standards. Strictly inspect chemical composition, mechanical properties and surface condition to eliminate cracks, impurities and other defects, then cut the qualified raw materials into standard fixed-length blanks with neat cutting surfaces and uniform size for stable forging processing.
2.Heating & Die Forging Forming:
Heat the finished blanks to standard forging temperature via industrial induction furnaces with precise temperature and time control to ensure uniform metal plasticity. Adopt closed-die forging for integral forming,which guarantees compact internal structure, regular shape and uniform wall thickness of threaded nipples, effectively avoiding forging deformation and structural defects.
3.Trimming, Straightening & Heat Treatment:
Remove forging flashes and excess materials, and conduct precision straightening to correct minor deformation for standard overall dimensions and flat end faces. Perform targeted heat treatment including normalization and stress relief for carbon steel and solution treatment for stainless steel to eliminate internal forging stress, enhance mechanical strength and improve corrosion resistance.
4.Precision Machining & Thread Processing:
Carry out turning and chamfering to finish plain or beveled ends that fit on-site assembly and welding requirements. Precisely machine standard NPT, BSPT and BSPP external threads with accurate thread pitch and smooth thread surface to ensure reliable sealing and connection performance.
5.Surface Finishing & Quality Inspection:
Remove internal and external burrs, oxide scales and rust, and implement polishing,cleaning or galvanizing treatments as required. Conduct full-range dimensional inspection on length, diameter, wall thickness and thread tolerance, together with visual inspection and nondestructive testing to eliminate all surface and internal defects.
6.Marking, Anti-rust Treatment & Warehousing:
Mark qualified products with material grade, specifications, execution standard and heat number. Complete professional anti-rust treatment and standardized packaging before classified warehousing and delivery.