Hammer unions for oilfield and industrial service from 1 inch to 4 inch, rated 2000 to 20000 psi working pressure, in figure 100 to figure 2202 configurations.
- Standard: API 6A, API 16C, ASTM A105, NACE MR0175, MSS SP-83
- Grades: A105, A350 LF2, F316, 4140
- Certificate: EN 10204 3.1 with every order, 3.2 on request
Mejor Steel is the export agent for the mills that make your material: one contract, one delivery date, and the mill named on the quotation. How we supply
We reply within one business day, Monday to Friday 09:00-18:00 CST. Or write to info@mejorsteel.com / WhatsApp.
Specifications
| Outer diameter | 1" - 4" (DN25 - DN100) |
|---|---|
| Length | Per figure type |
| Ends | Female, male, or wing nut, NPT or butt weld |
| Surface treatment | Black, galvanized, or painted |
| Manufacturing process | Forged and machined |
| Pressure rating | 2000 psi to 20000 psi working pressure, test to 30000 psi |
| Connection type | Hammer union, various figure numbers |
How a Hammer Union Works
A hammer union is a quick make and break pipe connection consisting of three parts: a male sub with a spherical or conical nose, a female sub with a matching seat, and a wing nut that draws the two together and is tightened with a hammer, which is where the name comes from. Sealing is by metal to metal contact of the two noses, or by an elastomer seal in some designs, and the wing nut provides the axial force that holds the seal in compression. The advantage is that a joint can be made and broken in seconds with a hammer, without threading or bolting, which is why hammer unions dominate cementing, fracturing and other oilfield manifold applications where lines are rigged up and down repeatedly. The trade-off is that the seal quality depends on correct make-up force, and hammer unions should not be used where a leak would be catastrophic without proper inspection and torque control.
Reading the Figure Numbers
The figure number identifies the design and the pressure rating of the union. The common oilfield figures run from FIG 100 through FIG 2202, with the higher numbers generally indicating higher pressure capacity. FIG 100 is a low pressure general service union, FIG 200 and FIG 206 are intermediate, FIG 400 and FIG 602 cover higher pressures used in mud and cement service, and FIG 1002, FIG 1502 and FIG 2002 are the high pressure unions used on fracturing and high pressure well servicing manifolds, with FIG 1502 rated to 15,000 psi working pressure and FIG 2002 to 20,000 psi. FIG 2202 is quoted at 15,000 psi for sour service, or higher by some makers, so confirm the figure and its rating on the manufacturer’s data sheet. One practical caution: the same figure number from different manufacturers is not necessarily dimensionally or pressure interchangeable, so confirm the specific manufacturer standard before mixing brands in a manifold.
Hammer unions: the figure number is the connection
A hammer union is a fast, reusable connection used on oilfield lines where assemblies are made and broken repeatedly. The figure number describes the size, the thread and the pressure rating together, so it is the figure number rather than the nominal size that has to be stated. The range of working pressures covered is very wide.
| Where the fitting sits | What it fixes in the specification | What to state on the enquiry |
|---|---|---|
| Cementing or fracturing manifold | A high pressure figure, tested well above the working pressure | the figure number, the end connection, and the working pressure |
| Temporary or quick connect line | A reusable joint made up by hand on site | the figure number, and the size |
| Mud or cement line on the rig | Standard oilfield figures | the end connection and the pressure rating |
| High pressure water or slurry service | The rating follows the service pressure, not the line size | the working pressure, and whether a test certificate is required |
| Sour service | Hardness restricted material | NACE MR0175 |
| Butt weld against threaded ends | The same figure number exists with different end finishes | the end connection required |
| Working pressure above 15000 psi | Only certain figures are rated that high | the pressure, so the correct figure is offered |
| Seals and spares | The elastomer choice follows the fluid | the fluid and the operating temperature |
What pressure can hammer unions handle?
It depends on the figure number. Common figures range from 2,000 psi cold working pressure for general low pressure service (FIG 200, 206 and 207) up to 15,000 psi (FIG 1502) and 20,000 psi (FIG 2002) for high pressure service; FIG 2202 is quoted at 15,000 psi for sour service, or higher by some makers. Each class is hydrostatically tested above its working pressure, and the exact rating belongs on the manufacturer’s data sheet. Always confirm the specific figure number and rating required rather than specifying by size alone.
Are hammer unions available in NACE compliant materials?
Yes. For sour service the union is supplied in a material that meets NACE MR0175 / ISO 15156, normally A105 with hardness controlled to 22 HRC maximum, or A350 LF2 for low temperature service, and in some cases stainless steel. Because the union contains a metal to metal seal under high contact stress, the hardness control is particularly important. Confirm that the certificate states NACE compliance when ordering for sour service.
Grades supplied and minimum properties
The grade fixes the minimum strength and the chemistry. The table below gives the requirements that separate the forged fitting grades ordered most often; the full composition and mechanical table for each grade is on its own page.
| Grade | Yield strength | Tensile strength |
|---|---|---|
| A105 (forged carbon steel) | 250 MPa (36,000 psi) | 485 MPa (70,000 psi) |
| F316 (forged stainless steel) | 205 MPa min (30,000 psi) | 515 MPa min (75,000 psi) |
The complete chemistry and mechanical table for each grade, with the notes that qualify it, is on the individual grade page – for example ASTM A105 flange. The stainless grade has the higher tensile requirement but the lower minimum yield strength, so the two are not interchangeable on the strength table alone. The working pressure of a hammer union is set by its own figure number, not by the material.
Source: specified minimum yield and tensile strength for each grade, per ASTM A105 / ASME SA105 and ASTM A182 / ASME SA182. The standard named against each grade is the governing document.
Download Hammer Unions data sheet (PDF) One page: supply range, grades and key sizes, what to state on the enquiry, and the inspection documents that come with the order. The standard is the governing document.
Materials
- Forged carbon steel
- Alloy steel
- Stainless steel
Typical applications
- Oilfield drilling and well servicing
- Cementing and fracturing manifolds
- High pressure mud and cement lines
- Temporary and quick connect piping
- High pressure water and slurry service
Inspection & testing
- Hydrostatic and pneumatic pressure test
- Dimensional inspection
- Hardness testing to NACE where applicable
- PMI on alloy and stainless steel
- Thread gauging
- Third-party inspection (SGS, BV, TUV)
| Packaging | Sea-worthy export packing: wooden cases or pallets, tagged with size, grade and heat number; corrosion protection on request. |
|---|---|
| MOQ | By piece - mixed sizes accepted; no minimum on standard items. |
| Lead time | Stock items: 5-10 days. Made to order: 3-5 weeks after order confirmation. |
Payment: T/T 30% deposit with the balance before shipment; L/C at sight also accepted. Final terms are confirmed on the quotation.
How we supply: sourced through partner mills; the producing mill is named on the quotation. How we supply sets out who is accountable for the order.
Need this product? Send the size, grade, quantity and destination port and we will reply with availability and pricing.
Request a quotation