Unique Spiral Groove Technology
As the worldwide leader in spiral groove technology, John Crane is the first to utilize non-contacting seals in cryogenic applications. The Type 285 can safely seal the most common industrial liquid gasses, such as liquid nitrogen, oxygen, argon and carbon dioxide. It fits the most popular cryogenic pumps — site-based and road tanker pumps — and meets liquid oxygen (LOX) safety standards. The John Crane spiral grooves enable the seal to operate on a gas film by gathering and compressing the vaporized liquid. As the gas is forced towards the closed groove ends, the pressure rises, which creates a cushion to separate the sealing faces. Since the seal faces do not contact, dry-running and face wear problems, which are associated with conventional contacting seals, are virtually eliminated.