New Vane Pumps From Denison

Diesel Progress North American Edition, April, 2001

Denison Hydraulics, Marysville, Ohio, has extended its fixed displacement vane pump product line with the introduction of three multisection models that feature new housings and improved power-to-weight ratios. The three new high-pressure units are designed for a variety of mobile and stationary applications, including mobile cranes, harvesters and winches.

The new pumps are the T6DDS, the T6DDCS and T67DDBS, with the designations referring to the range of configurations available in terms of number, displacement and pressure ratings of the cartridges in one housing. The T6DDS double pump has two standard T6D cartridges, while the T67DDBS triple pump uses a T7B rear cartridge rather than a T6C.

In the double pumps, displacements range from 2.9 cu.in./rev per stage to 9.64 cu.in./rev. Displacements for the triple pumps range from 0.35 cu.in./rev to 6.1 cu.in./rev. Operating speeds can range to 2500 rpm with 11 psia inlet pressure, depending on the application.

All of the pumps incorporate Denison's advanced vane pump design, which incorporates birotational, hydrostatically balanced cartridges and double lip vanes. Vane loading against the cam ring is accomplished through a pressure-fed pin under each vane rather than a spring or intra-vane. This means, Denison said, that loading is directly proportional to discharge pressure, reducing wear and preventing overshoot pressure vane blowoff. Higher pressures -- from 3500 to 4350 psi -- and operating speeds are possible with the pin-loaded design, the company said.

The use of a dry lubricant on the cam ring is also intended to improve wear resistance capability and extend pump life. It also improves start-up and break-in characteristics, according to the company.

The new pumps are manufactured at Denison's Vierzon, France, facility.