Hammer Union Seal (Lip Seal) is relatively large elastomeric annular seal that is rectangular in cross section, and used in hammer union-style pipe connections to establish flow lines and prevent leakage. The hammer union seal is “actuated” when it is compressed between the coupling components when they are cinched up. Hammer Unions are usually used in the Oil & Gas Industry, in steel mills, chemical plants, strip mining, and marine dredging. So the hammer union seal is exposed to the gases and fluids that flow through the coupling, making the choice of the optimum rubber compound important.

JST offers Hammer Union Seals from sizes 2" up to 5" of two lines, one from elastomer, another one from elastomer reinforced with anti-extrusion metal ring. The elastomer compounds could be NBR, HNBR, FKM, and compounds are available if there’s need for increased temperature and chemical resistance. The anti-extrusion rings can be reinforced Stainless Steel or Brass.

A swivel joint ball plug is usually working together with hammer union seals, to seal the balls of high pressure elbows and grease.

Contact us for more information and quotation.