Marzocchi GHP External Gear Pump

Marzocchi GHP Gear Pumps

High performances single pumps with aluminum body and cast iron flange and cover.  Displacements from 1.4 up to 87 cc/rev (Group 1, 2 and 3).  Available in different configurations (European, SAE, German standard) in single rotation or reversible version.  Suitable for heavy duty conditions.

SKU: Marzocchi_GHP_External_Gear_Pump Category:


  • The GHP gear pump usually consists of a gear pair supported by two aluminum bushes for groups 0.25, 0.5 and 1P, or bushes with plain bearings coated with anti friction material for groups 1, 2, 3 and 4, a body, a securing flange and a cover.
  • Shaft of the driving gear projecting beyond the flange mounts a twin-lip seal ring (the inner lip being a seal, the outer lip being a dust seal) for groups 0.25, 0.5 and 1P, or two opposed single-lip seal rings (the outer being a dust seal) for groups 1, 2, 3 and 4.
  • Pump body, flange and cover are made of special hi-resistant aluminum alloys for minimized deformation even when subject to high pressure, be it continuous or intermittent or peak pressure. The body is profiled by means of extrusion, whereas flange and cover are obtained by means of die-casting (even gravity die-casting for some models).
  • Gears are made of special steel. Their manufacturing process includes case-hardening and quench hardening. Then gears are ground and fine finished so to have a high degree of surface finishing. Proper tooth profile design and geometric proportions ensure low pulsation levels and low noise levels during pump operation. Bushes are made of special low-friction and hi-resistant aluminum alloy and manufactured from die-casting.
  • Special compensation zones onto flange and cover, insulated by special seals with anti-extrusion rings, allow fully free axial and radial movement to the bushes, which is proportional to pump operating pressure. In this way, internal dripping is dramatically reduced, thus ensuring very good pump performance (both in terms of volume and in general) and proper lubrication of pump moving parts.