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Self-Sealing Planetary Rotor Pump Revolutionizes Pump Applications

7 March 2000

Self-Sealing Planetary Rotor Pump Revolutionizes Pump Applications In Engines, Transmissions; Innovation From GKN Sinter Metals Offers Improved Performance & Efficiencies Over Conventional Piston Pump Systems

    AUBURN HILLS, Mich., March 7 A self-sealing planetary
rotor pump designed by GKN Sinter Metals is a revolutionary development for
pump applications in automotive and commercial vehicle engines and
transmissions, as well as for other industrial applications that demand high
pressures and high efficiencies across a wide rpm range.
    According to Harald Neubert, Vice President, Product Management & European
Sales, GKN Sinter Metals' proprietary planetary micro/macro gear design
(patent pending) "has been proven to reduce noise and energy consumption."
    The company's planetary rotor fits into conventional G-rotor housings with
only small modifications to achieve improved performance and efficiencies.  In
addition, the relationship of high pressures and unique volume flow
characteristics to rpm make this pump concept ideal for hydraulic pump
applications, which demand high performance from the very start of flow
control movement.
    "In these applications," says Dr. Neubert, "our planetary rotor pump can
outperform even piston pump systems."

    How GKN's Planetary Rotor Works
    GKN Sinter Metals' planetary rotor was designed with a unique self-sealing
mechanism whereby the tooth tip areas self adjust and tighten automatically.
This design feature eliminates the typical teeth flank clearance back flow
losses often generated by conventional G-rotor designs.
    The circular teeth of the planetary outer gears are driven by the inner
rotor while rolling over the micro teeth of the inner rotor.  Thus, they slide
freely in the open bores of the outer rotor without friction or a sliding
movement in the sealing function.

    Improvements at All RPM
    Because of this revolutionary design, GKN Sinter Metals' Planetary Rotor
Pump performs with high pressures and improved flow characteristics from as
low as 30 rpm to over 6500 rpm, covering virtually the entire spectrum of pump
industry needs.
    The planetary rotor's volumetric flow stays close to theoretical flow,
making it proportional to rpm while simultaneously providing extremely high
efficiencies at all pressures.  The pump exceeds traditional piston pump or G-
rotor pump efficiencies, with its typical drop at higher pressures, and it
does not lose volumetric efficiency at low control flows.

    Noise Reduction and Reduced Wear
    According to Dr. Neubert, GKN Sinter Metals' planetary rotor performs at a
substantially reduced noise level.  And its innovative micro/macro gear
rolling-over teeth concept, which results in drastically reduced friction,
extends the rotor's working life considerably.
    "Although complex in design," says Dr. Neubert, "this self-sealing pump is
ideally suited for P/M production, due to the net shape processing and minimal
waste in material that are features of our powder metal manufacturing
technology.
    "What does this mean for our customers?" asks Dr. Neubert.  "... a new
solution for their existing problems at lower costs."

    GKN Sinter Metals, with over 30 locations worldwide and business assets
spanning 13 countries and five continents, has annualized sales of
approximately $850 million and is the world's leading producer of powder metal
components.  The Company employs close to 7,000 people and produces over 5,000
different parts for the automotive, commercial vehicle, home appliance, lawn &
garden, office equipment, power tool, and recreational vehicle markets.  GKN
Sinter Metals is a wholly owned subsidiary of U.K.-based GKN plc, a global
industrial company.