AISI 4130 integral fittings
4130 integral fittings with hammer union ends
Tees, crosses, ells and laterals machined from one AISI 4130 forging, with hammer union ends and no welds, for temporary high-pressure lines that are rigged up and down.
An integral fitting is a tee, cross, ell, lateral or crossover machined from one forged body with its hammer union ends, so there is no weld between the fitting and its connections. We make them in AISI 4130, quenched and tempered, with male ends carrying a wing nut and female ends threaded to take it, to the figure number, size and service you specify, for frac, flowback, cementing, well test and other temporary high-pressure lines.
What integral means
A hammer union joins two subs: a male sub with a wing nut and a female sub with an external thread and a seal. The wing nut is struck with a hammer to make up the joint, which is why these lines go together and come apart quickly on a well site. On an integral fitting, those subs are not welded on; they are machined from the same forging as the body. That removes the weld, its heat-affected zone and the inspection it needs from the pressure boundary of a part that is moved, hammered and reused job after job.
Configurations
| Configuration | What it does | Typical ends |
|---|---|---|
| Tee | Branches a line, or joins two into one | M x F x F, F x M x M, F x F x F |
| Cross | Four-way junction at a manifold or wellhead | F x F x F x F, or mixed |
| Ell, 90° | Turns the line | M x F |
| Long sweep ell | Turns the line on a larger radius, for erosive flow | M x F |
| Lateral (wye) | Joins a line at 45° to the run | M x F x F |
| Crossover | Joins two figures or two sizes | For example 3 in FIG 1502 F x 2 in FIG 1502 M |
M = male sub with wing nut. F = female sub with seal. Ends are read in the order the drawing gives, run first.
The rest of the union-end range is on the flowline pages: hammer unions to weld or thread onto pipe, integral pup joints for straight runs, swivel joints and crossovers and bull plugs.
Figure numbers and pressure
The figure number on a hammer union sets its cold working pressure and its thread, and figures must never be mixed. These are the ratings union makers publish for the figures used on integral fittings:
| Figure | Cold working pressure, standard service | Sour gas version |
|---|---|---|
| FIG 602 | 6,000 psi | - |
| FIG 1002 | 10,000 psi | 7,500 psi |
| FIG 1502 | 15,000 psi | 10,000 psi |
| FIG 2002 | 20,000 psi | - |
| FIG 2202 | - | 15,000 psi |
Ratings as published by union makers, for example TechnipFMC for its Weco unions. Confirm against the drawing for the exact part. Details in the hammer union figures guide.
Why the figure matters, how the sour versions differ and what happened when 2 in figures were mixed on a rig are covered in hammer union figure numbers explained.
Material, heat treatment and sour service
Integral fittings are made from AISI 4130 and quenched and tempered to the strength the figure and size need. For hydrogen sulfide service they are tempered to 22 HRC maximum, as NACE MR0175 / ISO 15156-2 requires for low-alloy steels, and rated at the sour version's working pressure, for example 10,000 psi for FIG 1502.
A sour-service fitting is not a standard fitting with a lower number on it. It is heat treated, tested and marked differently, so state the service on every line of the order.
Marking
Each fitting is hard stamped with our mark, the figure number, size, cold working pressure, material and the heat number printed on its certificate, plus the sour service marking where it applies. The marking lets a crew check figure and rating at the wellhead before make-up, and lets an inspector trace the part to its test results.
Testing and documents
Each heat ships with an EN 10204 3.1 certificate showing chemistry, heat treatment, tensile and hardness results. Hydrostatic testing, Charpy impact testing, magnetic particle inspection of the threads and third-party witness can be added; tell us your specification and each test is listed in the quotation. See testing and documents.
Ordering
Integral tee, 2 in FIG 1502, M x F x F, AISI 4130 quenched and tempered, 15,000 psi CWP standard service, hydrostatic test at 22,500 psi, EN 10204 3.1, 10 pcs
Integral long sweep ell, 90°, 3 in FIG 1502, M x F, AISI 4130 quenched and tempered, sour service to NACE MR0175 / ISO 15156-2, 10,000 psi CWP, 22 HRC max, EN 10204 3.1, 4 pcs
Frequently asked questions
What does integral mean?
The body and its union connections are one piece: the male subs and the female sub are machined from the same forging as the tee, cross or ell, so there is no weld anywhere in the pressure boundary.
Can a FIG 1502 fitting be used in sour service at 15,000 psi?
No. The standard FIG 1502 is rated 15,000 psi cold working pressure; its sour gas version is rated 10,000 psi. For 15,000 psi sour service, union makers offer FIG 2202. Order the figure and the service together and the fitting is made and marked for it.
Are integral fittings hydrostatically tested?
Tell us the test pressure and hold time your specification calls for, often 1.5 times the cold working pressure. The test is listed in the quotation and the results go on the certificate.
Do you supply the wing nuts and seals?
Male ends are supplied with their wing nut. Tell us if you need spare seal rings or nuts for the female ends, and the elastomer for your service.