The function, applications, and system considerations are described for a load-sensing hydraulic flow control valve. A fluid-linked power steering system is used for illustrations, but the same principles can apply to any circuit using a special four-way valve. The valve functions in all systems: open center, closed center, and load sensing. Advantages of this type of control include: only the flow demanded by the vehicle operator for a steering maneuver going to the steering circuit; priority of steering function over other system functions; availability of undemanded flow to other circuits; improved steering control regardless of steering load pressure; and a new versatility in system design. The flow control valve can be used in systems to coordinate several pumps or pressure reserves, to provide abnormal peak flows to some circuits, or to provide alternate sources on failure. In use for about ten years, this type of valve received new attention during the fuel crisis of 1974 when interest was renewed in load-sensing systems to conserve energy.

  • Availability:
  • Supplemental Notes:
    • Presented at SAE Off-Highway Vehicle Meeting and Exposition, Milwaukee, Wisconsin, 11-14 September 1978.
  • Corporate Authors:

    Society of Automotive Engineers (SAE)

    400 Commonwealth Drive
    Warrendale, PA  United States  15096
  • Authors:
    • Johnson, O W
  • Publication Date: 1978

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00396999
  • Record Type: Publication
  • Source Agency: National Highway Traffic Safety Administration
  • Report/Paper Numbers: SAE 780728, HS-025 567U
  • Files: HSL, USDOT
  • Created Date: Aug 31 1985 12:00AM