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Oil-less Piston

THOM_688Q-VAC priming systems using oil-less WOB-L Piston vacuum pumps are a great choice for small, portable priming systems.  Unlike the more conventional articulated piston pump, the WOB-L piston has no gudgeon pin (wrist pin) connecting the piston rod to the piston. Instead, the piston and piston rod are a single item, usually a single casting. The piston rod is mounted to an eccentric bearing assembly, which in turn is mounted to the motor shaft to convert rotary energy from the motor into linear motion of the piston within the cylinder.

The piston is sealed to the cylinder by a flanged disk that forms both a seal and mechanical guide for the piston. It runs without lubrication in contact with a low friction, surface coated cylinder of high heat conductivity. As the piston is driven up and down, air resistance on the upward stroke expands the disk’s seal on the piston against the cylinder wall to increase its efficiency, while compensating for the ‘wobble’ action.

The oil-free operation and exceptional performance characteristics make the WOB-L piston extremely popular in a variety of industries.  One specific advantage is of the design is the failure mode is a gradual fatigue, rather than a catastrophic failure which is a characteristic of many other designs.  WOB-L piston pumps provide flow rates to 5.4 acfm and maximum vacuum levels to 27” HgV.

THOM_688Q-VAC priming systems using oil-less WOB-L Piston vacuum pumps are a great choice for small, portable priming systems.  Unlike the more conventional articulated piston pump, the WOB-L piston has no gudgeon pin (wrist pin) connecting the piston rod to the piston. Instead, the piston and piston rod are a single item, usually a single casting. The piston rod is mounted to an eccentric bearing assembly, which in turn is mounted to the motor shaft to convert rotary energy from the motor into linear motion of the piston within the cylinder.

The piston is sealed to the cylinder by a flanged disk that forms both a seal and mechanical guide for the piston. It runs without lubrication in contact with a low friction, surface coated cylinder of high heat conductivity. As the piston is driven up and down, air resistance on the upward stroke expands the disk’s seal on the piston against the cylinder wall to increase its efficiency, while compensating for the ‘wobble’ action.

The oil-free operation and exceptional performance characteristics make the WOB-L piston extremely popular in a variety of industries.  One specific advantage is of the design is the failure mode is a gradual fatigue, rather than a catastrophic failure which is a characteristic of many other designs.  WOB-L piston pumps provide flow rates to 5.4 acfm and maximum vacuum levels to 27” HgV.