Alloy Steel Buttweld Fittings Manufacturer | ASTM A234 WP11/WP91

Alloy Steel Buttweld Fittings Supplier & Exporter in India

Alloy Steel Buttweld Fittings are the essential elements of piping systems that are used to connect pipes and regulate the direction of flow in the extreme pressure and temperature conditions. These fittings are made of high-grade alloy steel and provide superior strength, corrosion resistance, and durability in harsh industrial conditions.

ASTM A234 Buttweld Fittings are commonly used in industries that demand a high degree of performance in severe service environments and therefore are the standard of fittings used in critical applications. Sold in 1/8 inch NB through 48 inch NB, custom thicknesses, and in a variety of schedules — all fittings are produced to ASTM/ASME A/SA 234 and are accompanied by complete Mill Test Certificates.

Need high-quality Alloy Steel Buttweld Fittings or Alloy Steel Fittings to use in your project? Contact our team to receive competitive prices, technical assistance and quick delivery.

Alloy Steel Buttweld Fittings Specifications

Standard	Size Range	Dimensions	Grade	Thickness	Type
ASTM A234	1/8″ NB to 48″ NB	ASME B16.9 / B16.28	WP1, WP5, WP9, WP11, WP22, WP91	Sch 5S – XXS	Seamless / Welded
ASME SA234	Custom on request	MSS-SP-75 / MSS-SP-43	WP12	Custom	Seamless / Welded

Available with IBR approval. Material traceability documentation provided for every lot. Third-party inspection by SGS / Bureau Veritas / Lloyds available.

ASTM A234 Grades Supplied

These grades ensure high-temperature strength, resistance to oxidation, and creep resistance across a range of service temperatures and pressures.

Chemical Composition — All ASTM A234 Alloy Steel Grades (%)

Grade	C max	Mn	Si	S max	P max	Cr	Mo	Other
WP1	0.28	0.30–0.80	0.10–0.50	0.045	0.045	—	0.44–0.65	—
WP5	0.15	0.30–0.60	0.50 max	0.030	0.030	4.0–6.0	0.45–0.65	—
WP9	0.15	0.30–0.60	1.00 max	0.030	0.030	8.0–10.0	0.90–1.10	—
WP11 Cl.1	0.05–0.15	0.30–0.60	0.50–1.00	0.030	0.030	1.00–1.50	0.44–0.65	—
WP11 Cl.3	0.10–0.20	0.30–0.80	0.50–1.00	0.030	0.030	1.00–1.50	0.44–0.65	—
WP12	0.05–0.15	0.30–0.61	0.50 max	0.045	0.045	0.80–1.25	0.44–0.65	—
WP22	0.05–0.15	0.30–0.60	0.50 max	0.030	0.030	1.90–2.60	0.87–1.13	—
WP91	0.08–0.12	0.30–0.60	0.20–0.50	0.010	0.020	8.0–9.5	0.85–1.05	V, Nb, N

Mechanical Properties of ASTM A234 Alloy Steel Buttweld Fittings

Grade	Tensile Strength (MPa min)	Yield Strength (MPa min)	Elongation % min	Hardness (HBW max)
WP1	415	205	30	197
WP5	415	205	30	197
WP9	415	205	30	197
WP11 Cl.1	415	205	30	197
WP11 Cl.3	415	240	22	197
WP12	415	220	22	197
WP22	415	205	30	197
WP91	585	415	20	248

Heat Treatment Requirements for ASTM A234 Alloy Steel Buttweld Fittings

WP5, WP9, WP22, and WP91 grades are supplied in the full-annealed, isothermal-annealed, or normalized-and-tempered condition per ASTM A234. Tempering temperatures are maintained above 620°C (WP11) and 675°C (WP5/WP9/WP22) to meet mechanical property requirements. WP91 is supplied normalized at 1040°C min and tempered at 730–800°C. Certificates confirming heat treatment are supplied with every order.

Dimensions & Standards

Our Alloy Steel Pipe Fittings comply with the following international standards:

ASME B16.9 | ASME B16.28 | MSS-SP-75 | MSS-SP-43

Types Of Alloy Steel Buttweld Pipe Fittings

Each fitting type is available in seamless and welded construction, conforming to ASME B16.9, B16.28, and MSS-SP-43. Sizes range from 1/8″ NB to 48″ NB across schedule 5S through XXS. Custom fabricated fittings are available on request with full documentation.

Need Alloy Steel Buttweld Fittings for a high-temperature or high-pressure application?

Contact Amardeep Steel Centre for pricing, stock availability, and custom size enquiries. We supply ASTM A234 WP5 / P9 / P11 / P22 / P91 fittings with full MTC documentation, third-party inspection, and fast dispatch from Mumbai.

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Applications of Alloy Steel Buttweld Fittings

Alloy Steel Buttweld Fittings are widely used across high-temperature and high-pressure industrial processes:

Oil & Gas Industry
Petrochemical Plants
Power Generation
Refineries
Chemical Processing
High-Pressure Hydraulics
Cement Industry

Packaging, Testing & Documentation for Alloy Steel Buttweld Fittings

All Amardeep Steel Centre Alloy Steel Buttweld Fittings are supplied with complete documentation and tested to international standards. Each shipment includes:

Mill Test Certificate: EN 10204 / 3.1 with every order
Raw Material Certificate: Heat and lot traceability documentation
Heat Treatment Chart:Confirming treatment condition per grade
Third-Party Inspection Report: SGS, Bureau Veritas, or TÜV on request
100% Radiography Test Report: Where applicable / on request
NABL-Approved Lab Tests: PMI, Hardness, Hydrostatic, Impact testing
Packaging: Wooden crates or fumigated export packing; individual fitting marking: Grade, Heat No., Size, Schedule

Why Choose Amardeep Steel Centre

Established in Mumbai, Amardeep Steel Centre has supplied alloy steel fittings to global OEMs, EPCs, and distributors across 80+ countries for over two decades. We serve the oil & gas, power, petrochemical, and cement industries with a commitment to quality and traceability at every stage.

Certified Materials

ISO 9001, IBR, PED compliant

Competitive Pricing

Direct manufacturer, no middlemen

Global Export

80+ countries, full export documentation

Quality Control

NABL lab, 100% incoming inspection

We export Alloy Steel Buttweld Fittings to the following countries (among 80+ worldwide).

Frequently Asked Questions - Alloy Steel Buttweld Fittings

What are ASTM A234 Buttweld Fittings?

ASTM A234 fittings are alloy and carbon steel pipe fittings designed for moderate and high-temperature services. They are widely used in oil & gas, power generation, and petrochemical industries, and conform to ASME B16.9 and B16.28 dimensional standards.

What is WPB in alloy steel fittings?

WPB refers to a grade under ASTM A234 indicating material strength and chemical composition suitability for standard pressure-temperature service. WPB is a carbon steel grade, while WP5, WP9, WP11, WP22, and WP91 are chromium-molybdenum alloy steel grades for elevated-temperature service.

What is the difference between ASTM A234 WP11 and WP91 alloy steel fittings?

WP11 (1.25% Cr, 0.5% Mo) is used for moderate-temperature service up to 550°C. WP91 (9% Cr, 1% Mo + V, Nb) is specified for high-temperature power generation service up to 600°C, with significantly higher creep resistance. WP91 also has a higher tensile strength minimum of 585 MPa versus 415 MPa for WP11.

Do your alloy steel buttweld fittings come with material test certificates?

Yes. Every supply is accompanied by EN 10204 / 3.1 Mill Test Certificates. Third-party inspection certificates from SGS, Bureau Veritas, or Lloyds are available on request. We also provide NABL-approved lab test reports including PMI, hardness, hydrostatic, and radiography where applicable.

What sizes are available for ASTM A234 alloy steel buttweld fittings?

We supply in sizes 1/8 NPS to 48 NPS, across wall thicknesses from Schedule 5S to XXS including custom schedules. Custom fabricated fittings with special dimensions are available on request with full documentation.

Which industries use alloy steel buttweld fittings?

Oil & gas, petrochemical, power generation (boilers, turbines), cement, pharmaceutical, and high-pressure hydraulic systems. The chromium-molybdenum grades (WP5, WP9, WP11, WP22, WP91) are particularly favoured in boiler tube headers, pressure vessels, and superheater connections.

What standards do these fittings follow?

They follow ASME B16.9 (Factory-Made Wrought Buttwelding Fittings), ASME B16.28 (Short-Radius Elbows and Returns), MSS-SP-75, and the ASTM A234 material specification.