New Seal Technology Improves Last-Century Forging Presses

For decades the forging industry had relied exclusively on the standard molded rubber seals stacked in sets known as V-packing. But most of these seals are easily susceptible to shredding by the scarred and damaged forging rams that date as far back as the 1930s. For some companies, replacing the seals has become a monthly event. It’s expensive and time consuming, and downtime costs as much as $1 million in lost productivity. 

These timeworn rams narrow at their core, creating an hourglass shape that renders conventional rubber seals deficient. The irregular shape allows oil to weep and increases the threat of extrusion. Making matters worse, the bronze bushings are typically long worn low, increasing dependence on the seals to perform under even greater pressure.

Knowing this, System Seals set out to advance the technology and provide the forging industry with the next generation of V-packing that would long outlive the industry standby, and allow these historic presses for forge on more reliably.

Engineers recognized that rubber did, in fact, provide an effective seal – when they remained intact. But they needed greater abrasion resistance against the rough rams and a more compliant lip that maintained contact, especially at the narrowing of the hourglass.

System Seals engineered a new V-packing system that includes at least one polyurethane seal, used in combination with rubber seals. Researchers discovered that polyurethane resists the scored surfaces of the ram, while allowing the rubber to remain intact and perform substantially longer.

Tested in System Seals’ research facility, the rubber and polyurethane worked best together, along with a female adapter made from polymides. System Seals dubbed the new combination the Elite set, and it remains the only system of its kind on the market today.

Because every press differs greatly, System Seals custom designs V-packing for each individual ram, and the new approach is outlasting traditional all-rubber seals by more than 100 percent. For large presses on a monthly replacement schedule, that’s about $6 million per year in new found productivity.