Carbon Steel High Yield Pipe Fittings Supplier

Solitaire Overseas supplies carbon steel high yield pipe fittings in ASTM A860, Grades WPHY42 through WPHY70, engineered to match the strength of API 5L X-grade line pipe used in cross country oil and gas transmission. Manufactured to ASME B16.9 for NPS 14 inch and below, with MSS SP-75 covering larger sizes up to NPS 48 inch, these fittings are heat treated and impact tested to maintain toughness alongside high yield strength. Every batch ships with a mill test certificate, and dual certification with ASTM A420 WPL6 for low temperature toughness can be arranged on request.

Need the matching low temperature or standard grade for other sections of the same pipeline?

See our Carbon Steel Low Temperature Pipe Fittings range, or contact our team about dual certified options.

Mechanical Properties, Compatible Pipe Grades and Dimensional Reference

Specifications Mechanical Properties Compatible API 5L Dimensional Standard

Carbon Steel High Yield Pipe Fittings Specifications

Parameter	Specification
Standard	ASTM A860 (WPHY42, 46, 52, 56, 60, 65, 70)
Dimensional Standard	ASME B16.9 up to NPS 14"; MSS SP-75 above NPS 14"
Size Range	NPS 2" to 48"
Compatible Pipe	API 5L X42 to X70 grades
Heat Treatment	Normalized, quenched and tempered, or stress relieved (mandatory for all grades)
Impact Test	Charpy V-notch, typically at -45°C
Hardness	22 HRC (235 HBW) max
Certification	Mill Test Certificate EN 10204 3.1, 3.2 on request

Mechanical Properties by Grade

Grade	Yield Strength min (MPa)	Tensile Strength Range (MPa)	Elongation min (%)
WPHY42	290	415 – 585	25
WPHY46	315	435 – 605	25
WPHY52	360	455 – 625	25
WPHY60	415	515 – 690	20
WPHY65	450	530 – 705	20
WPHY70	485	550 – 725	20

Compatible API 5L Pipe Grades

ASTM A860 Fitting Grade	Compatible API 5L Pipe Grade
WPHY42	X42, X42M, X42Q
WPHY46	X46, X46M, X46Q
WPHY52	X52, X52M, X52Q
WPHY60	X60, X60M, X60Q
WPHY65	X65, X65M, X65Q
WPHY70	X70, X70M, X70Q

Dimensional Standard by Size

Size Range	Governing Dimensional Standard
NPS 14" and below	ASME B16.9
Above NPS 14" up to NPS 48"	MSS SP-75

Types of Carbon Steel High Yield Pipe Fittings

Elbows (45°, 90°) in WPHY42/46/52/56/60/65/70
Equal and Reducing Tees
Concentric and Eccentric Reducers
Caps and Crosses
Stub Ends

Applications of Carbon Steel High Yield Pipe Fittings

Cross country gas and oil transmission pipelines
High pressure distribution networks
Gas gathering and distribution networks
Compressor and pump station piping
Subsea and offshore pipeline tie-ins

ASTM A860 vs MSS SP-75 - Which Specification Applies

Both standards cover high strength butt weld fittings for pipeline service, but they are not identical in stringency. Use this table to understand the difference.

Criteria	ASTM A860	MSS SP-75
Governing Body	ASTM International	Manufacturers Standardization Society
Stringency	More stringent: mandatory Charpy impact testing, tighter chemistry and thermal processing	Baseline requirement, widely used across US pipelines
Common Region	Outside the US, colder environments	Most common requirement for US pipelines
Dual Certification	Can be dual certified to MSS SP-75	Can be dual certified to ASTM A860
Learn More	This page	Contact us to confirm your project's governing specification

Frequently Asked Questions

Which API 5L pipe grades match ASTM A860 WPHY fittings?

WPHY42 pairs with API 5L X42, WPHY52 with X52, WPHY60 with X60, WPHY65 with X65, and WPHY70 with X70, matching minimum yield strength between pipe and fitting.

Are A860 fittings the same as MSS SP-75 fittings?

ASTM A860 and MSS SP-75 both cover high strength butt weld fittings, but A860 is the more stringent specification with mandatory Charpy impact testing; fittings can be dual certified to both where required.

Can high yield fittings be supplied for low temperature service too?

Yes, some ASTM A860 fittings are dual certified with ASTM A420 WPL6 to cover both high yield strength and low temperature impact toughness in a single fitting.

What is the size range for ASTM A860 WPHY fittings?

ASTM A860 fittings are produced from NPS 2 inch up to NPS 48 inch, with ASME B16.9 governing dimensions up to NPS 14 inch and MSS SP-75 covering larger sizes.

Is heat treatment mandatory for WPHY fittings?

Yes, all ASTM A860 WPHY grades must be heat treated by normalizing, quenching and tempering, or stress relieving, unlike standard A105 forged fittings where heat treatment is optional.

What hardness limit applies to high yield fittings?

ASTM A860 fittings carry a maximum hardness of 22 HRC (235 HBW) to help resist hydrogen induced cracking in sour gas and oil transmission service.