Hammer Unions

We are the manufactures of Hammer Unions, from raw materials in the form of forgings or castings in accordance with service requirements in sizes 1 to 12″ with ratings up to 20,000 PSI cold working pressure. Unions for sour gas service are manufactured in accordance with NACE MR-01-75 & API RP-14E.

Our Hammer Unions are manufactured with industry standards so it can interchangeable with other manufacturers.

Acme thread and line pipe threads are gauged by standard plug & ring gauges.

The conical and spherical surfaces of the female and male subs respectively form an effective metal-to-metal seal in case of low pressure services. For medium pressure mostly an ‘O’ ring is provided in the male sub in addition to the metal to metal seal. For high pressure a lip type seal ring is provided for primary seal in the female sub. The seal protects the secondary metal to metal seal from corrosion and limits fluid flow turbulence. For sour service applications viton seals are provided.

We manufacture unions using modern manufacturing techniques to attain first class workmanship and dimensional control. Correctly chosen raw materials for a particular service together with correct heat-treatment process is used to ensure better service and longer life in extreme conditions.

Notes
- Line pipe threads for Pipe diameters above 4″ are not recommended for sour service application.
- 4″ & 5″ sizes are rated at 7500 PSI cold working pressure and 12000 PSI test pressure.
- Sour gas service unions are painted OLIVE GREEN and stamped “NACE”.
- For other types of threading like casing, tubing or NPS thread seal configuration contact us.

The low pressure and suction union are made from carbon steel. The nut and O-ring are common in both sizes. Available in 4″ or 5″ sizes in threaded & socket welded connection. These unions are suitable for 500 PSI working pressure.

Quick reference table for union end connections and pressure ratings

Presure Rating (PSI) End Connections
Standard Service Sour Service
C.W.P. T.P. C.W.P. T.P.
500 750 - - LINE PIPE
1000 1500 - - LINE PIPE
2000 3000 - - LINE PIPE / BUTT WELD
2000 3000 - - LINE PIPE / BUTT WELD
2000 3000 - - LINE PIPE / BUTT WELD
2000 3000 - - LINE PIPE
2500 3750 2500 3750 LINE PIPE / BUTT WELD
4000 6000 4000 6000 LINE PIPE / BUTT WELD
6000 9000 - - LINE PIPE / BUTT WELD
6000 9000 6000 9000 LINE PIPE / BUTT WELD / NPTS
10000 15000 7500 12000 LINE PIPE / BUTT WELD / NPTS
10000 15000 7500 12000 LINE PIPE / BUTT WELD
10000 15000 7500 12000 LINE PIPE / BUTT WELD / NPTS
15000 22500 10000 15000 LINE PIPE / BUTT WELD / NPTS
20000 30000 - - BUTT WELD
- - 15000 22500 BUTT WELD