Flowline Connections
FracSync supplies hammer unions for frac, flowback, well testing, cementing and well service lines. Available in 1" to 4" sizes in Figure 100 to Figure 2002 connections, including Figure 1502 for 15,000 psi service, in standard and sour (H2S) service.

Pressure Chart
The figure number of a hammer union shows its pressure class. Always match the figure number on both halves – unions of different figures must never be connected.
| Figure | Typical cold working pressure | Common use |
|---|---|---|
| Figure 100 | 1,000 psi | Low-pressure water, air and fluid transfer lines |
| Figure 200 | 2,000 psi | Mud, water and low-pressure oilfield lines |
| Figure 400 | 4,000 psi | Medium-pressure service and production lines |
| Figure 602 | 6,000 psi | Mud, cementing and medium-pressure manifold lines |
| Figure 1002 | 10,000 psi | High-pressure well service and test lines |
| Figure 1502 | 15,000 psi | Frac iron, flowback, cementing and high-pressure manifolds |
| Figure 2002 | 20,000 psi | Very high-pressure frac and well service |
Ratings shown are typical industry values for each figure. Confirm the rating stamped on the union and on your equipment before use. Figure 300 and other figures available on request.
How It Works
A hammer union is a quick-connect fitting that joins two sections of pipe or flowline without welding. It has three parts: a male sub, a female sub and a wing nut. The nut is tightened with a sledgehammer on its lugs, which pulls the two subs together and seals the joint.
Because they connect and disconnect in minutes, hammer unions are the standard connection on temporary high-pressure lines – 1502 plug valves, pup joints, swivel joints, tees and crosses all use them.
Male vs Female
Sizes
The standard size for frac iron, flowback, cementing and well testing lines.
Used on frac and flowback spreads that need higher flow rates.
For high-rate flowback, production test and manifold lines.
1" to 4" sizes available. Other sizes on request.
Safety
FAQ
Figures, pressure ratings, sizes and safe use.
A hammer union quickly connects two sections of pipe or flowline without welding. It is used on frac iron, flowback, cementing, well testing and other temporary high-pressure lines.
A Figure 1502 hammer union is typically rated for 15,000 psi cold working pressure. It is the most common union on frac and flowback lines.
The male half carries the wing nut. The female half has the external thread that the nut screws onto, and usually holds the seal ring.
No. Unions of different figures are not designed to work together. Some can partly connect and then fail under pressure, so always match the figure number on both halves.
We supply hammer unions in 1" to 4" sizes. The 2" size is the most widely used on frac and flowback lines.
Yes. We supply hammer unions for standard service and for sour (H2S) gas service.
Related Products
FracSync supplies high-quality flow control products engineered for performance, reliability, and safety in the most demanding oil & gas environments.
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