Hangbo Alloy Group
Shanghai · Est. 2012
Wrought and forged nickel alloy pipe fittings for corrosive, high-temperature and high-pressure process piping - manufactured to ASTM B366, ASME B16.9, B16.11 and B16.28.
Nickel alloy pipe fittings are the connection points where a corrosion-resistant or high-temperature piping system is most vulnerable. Wall thickness changes at an elbow, the stress concentration at a tee intersection and the crevice geometry of a socket weld all create local conditions that are more aggressive than the straight pipe run. Hangbo Alloy Group supplies a complete range of wrought and forged nickel alloy fittings designed to match the metallurgy, wall schedule and pressure rating of the pipe they join, so that the fitting never becomes the weak link in the line.
Our fittings programme covers buttweld fittings for welded process piping per ASME B31.3 and B31.1, forged socket-weld and threaded fittings for small-bore instrumentation and utility lines, and lap joint stub ends for use with nickel alloy flanges in systems that require frequent dismantling. Every fitting is supplied in the same alloy family and heat treatment condition as the matching nickel alloy seamless tubes and pipes, which avoids the galvanic mismatch and weld dilution problems that occur when fittings are sourced separately from the line pipe.
Typical service environments include sulphuric and hydrochloric acid plant, wet chlorine and caustic handling, seawater cooling and ballast systems, flue gas desulphurisation scrubbers, LNG cryogenic transfer, offshore topside process piping, and high-purity chemical and pharmaceutical loops where iron contamination must be controlled.
Our standard manufacturing range covers the following fitting families and dimensional standards:
Wall thickness follows ASME B36.19M for stainless and nickel alloy pipe, in schedules 5S, 10S, 40S and 80S, with heavier walls available for high-pressure duty. Dimensional tolerances, end preparation (bevel angle 30° +5°/-0° with 1.6 mm root face per ASME B16.25) and centre-to-end dimensions conform to the governing ASME standard for each fitting type. Non-standard geometries, long-radius sweeping bends with R = 3D to 10D, and integrally reinforced branch outlets can be produced against customer drawings.
Nickel alloy fittings are produced in the full commercial grade family, each selected for a distinct corrosion or temperature envelope:
All wrought fittings are supplied in the solution-annealed and pickled condition unless otherwise specified. Inconel 718 can be supplied solution-treated, or solution-treated and aged to achieve the higher strength levels required by sour-service design. Where chloride stress corrosion cracking is the controlling failure mode, grade selection should be reviewed against our chloride SCC guide for nickel alloys before the order is placed.
Buttweld fittings start from seamless nickel alloy pipe produced to ASTM B444, B423, B165, B167, B407 or B729 as applicable, which is then cut to length and hot-formed over a mandrel or by the cold-forming extrusion route for smaller sizes. Hot forming is carried out within the temperature window specific to each alloy - too low and the material work-hardens and cracks, too high and grain growth or sensitisation degrades corrosion performance. After forming, every fitting receives the full solution anneal and rapid quench specified by the material standard, followed by descaling and passivation to restore the chromium-rich passive film.
Forged fittings to ASME B16.11 are produced from billet on closed-die hammers or presses, then rough-machined, solution-treated and finish-machined. Threads are cut to ASME B1.20.1 (NPT) or ISO 228-1 (BSPP) and gauged. Socket weld bores are machined to the B16.11 bottoming clearance so that the pipe cannot bottom out before the weld is made - a frequent cause of weld cracking in small-bore nickel piping.
Heat treatment is performed in calibrated furnaces with full chart recording, and each heat treatment batch is traceable to the heat number of the source bar or pipe. Repair by welding is not performed on finished fittings without written customer approval and a documented repair procedure.
Hangbo Alloy Group operates a quality management system certified to ISO 9001:2015, GJB 9001C and GOST R. Every fitting shipment is delivered with an EN 10204 3.1 inspection certificate, and EN 10204 3.2 certification can be arranged with third-party witness by BV, SGS, TUV, DNV or Lloyd's Register.
Standard verification includes: positive material identification (PMI) by handheld XRF on 100% of finished fittings or by spectrographic analysis on each heat; dimensional inspection against the governing ASME standard; visual and dye penetrant examination of all forming surfaces; hydrostatic or pneumatic testing of forged fittings where required by class; and review of the certified chemical analysis and mechanical test results from the source melt. For critical service, supplementary testing such as intergranular corrosion testing to ASTM G28 Method A, ultrasonic examination, radiography of weld seams, and ferrite or grain size checks can be specified at the enquiry stage.
Fittings are marked by laser or low-stress dot peening with the alloy designation, heat number, size, schedule, standard and manufacturer's mark, and are packed in plywood cases with end protectors to prevent bevel damage in transit. Full heat-to-heat traceability is maintained from the melt through to the finished fitting.
They work together rather than compete. ASTM B366 / ASME SB366 defines the material - the chemical composition, mechanical properties and heat treatment of factory-made wrought nickel and nickel alloy fittings. ASME B16.9 defines the dimensions, tolerances and pressure ratings of the fitting itself. A compliant fitting must satisfy both: B366 for what it is made of, B16.9 for its shape and size. Forged socket-weld and threaded fittings are additionally covered by ASME B16.11 for dimensions and pressure class.
Standard buttweld fittings are stocked and produced from 1/2" NPS (DN15) to 24" NPS (DN600) in schedules 5S, 10S, 40S and 80S per ASME B36.19M. Larger diameters up to 36" and heavier walls for high-pressure duty are manufactured to order. Forged fittings to ASME B16.11 are supplied from 1/8" to 4" in 2000, 3000 and 6000 lb pressure classes.
We routinely produce fittings from pipe or bar that is matched to the chemistry of the line pipe, and we can target a narrow composition range within the specification limits to keep weld dilution and galvanic potential predictable. Heat-to-heat traceability is documented on the EN 10204 3.1 certificate. Where an exact heat match is required, the most practical route is to place the pipe and the fittings on the same order so that both are cut from the same melt.
Send us your grade, diameter, length, quantity, and any special requirements. Our team responds within 10 minutes during business hours.