Hydraulic Pumps

Supply and Repair

We have been offering this service to our customers for many years allowing us to provide a service which is prompt and affordable. We supply & repair all makes & models including old and obsolete units.

Many pumps are scrapped every year because they are considered to be beyond economical repair when it has been possible to have them repaired by professional hydraulic engineers.

Our

Repair Centre

  • We strip, assess and quote FREE OF CHARGE.
  • We test to the original equipment specifications.
  • Average pump repair time is between 2-5 days*
  • Book your repair with us today!

*We also offer a faster breakdown service. Times subject to change depending on workload and available spares.

 

Gear Pumps

Gear pumps are positive displacement rotary pumps used to transport high pressure and high volume flows. They function through the use of two or more internal gears that create vacuum pressure, propelling the fluid media. Typically a rotating assembly includes a driving gear and a driven gear. As each tooth of the gear makes contact, the load moves to the next tooth and fluid moves with each contact. Internal gear pumps or “gear within a gear” pumps may have their smaller gear turning in the same direction as the larger gear, creating suction to move the pumped fluid media. At various points during the process of turning, the gears create a seal between the inlet and outlet sides of the rotation assembly chamber or body.

Gear pumps provide a comparably continuous, non-pulsating flow in relation to diaphragm pumps or peristaltic pumps. For this reason, gear pumps may be preferred in a number of applications from laboratory to petrochemical and marine applications, and processes involving hydraulic presses and dry pit steam power.

Gear pumps are reliable when using media with heavier viscosities, however, build up or interference within the internal mechanisms may cause the gears to rotate more slowly. The addition of a pressure relief valve to the system may help to alleviate some of this slow down, and provide a longer life cycle as well.

Rotary Vane Pumps

Rotary vane pumps (fixed and simple adjustable displacement) have higher efficiencies than gear pumps, but are also used for mid pressures up to 180 bar (18,000 kPa) in general. Modern units can exceed 300 bar (30,000 kPa) in continuous operation, although vane pumps are not regarded as “high pressure” components.

Some types of vane pumps can change the centre of the vane body, so that a simple adjustable pump is obtained. These adjustable vane pumps are in general constant pressure or constant power pumps: the displacement is increased until the required pressure or power is reached and subsequently the displacement or swept volume is decreased until equilibrium is reached.

A critical element in vane pump design is how the vanes are pushed into contact with the pump housing, and how the vane tips are machined at this very point. Several type of “lip” designs are used, and the main objective is to provide a tight seal between the inside of the housing and the vane, and at the same time to minimize wear and metal-to-metal contact. Forcing the vane out of the rotating centre and towards the pump housing is accomplished using spring-loaded vanes, or more traditionally, vanes loaded hydro-dynamically (via the pressurized system fluid).

Bent Axis Pumps

Bent axis pumps, axial piston pumps and motors using the bent axis principle, fixed or adjustable displacement, exists in two different basic designs. The Thoma-principle with max 25 degrees angle and the Wahlmark-principle with spherical-shaped pistons in one piece with the piston rod, piston rings, and maximum 40 degrees between the driveshaft centreline and pistons. These have the best efficiency of all pumps.

Although in general the largest displacements are approximately one litre per revolution, if necessary a two-liter swept volume pump can be built. Often variable-displacement pumps are used, so that the oil flow can be adjusted carefully. These pumps can in general work with a working pressure of up to 350–420 bars in continuous work.

Piston Pumps

Piston pumps are reciprocating pumps that use piston to move media through a cylindrical chamber. The piston is actuated by a steam powered, pneumatic, hydraulic, or electric drive. Piston pumps are also called well service pumps, high pressure pumps, or high viscosity pumps.

Piston pumps use a cylindrical mechanism to create a reciprocating motion along an axis, which then builds pressure in a cylinder or working barrel to force gas or fluid through the pump. The pressure in the chamber actuates the valves at both the suction and discharge points. Plunger pumps are used in applications that range from 70 – 2070 BAR.

Piston pumps are used in lower pressure applications. The volume of the fluid discharged is equal to the area of the piston. The capacity of the piston pumps can be calculated with the area of the piston, the number of pistons, the displacement of the stroke and the speed of the drive. The power from the drive is proportional to the capacity of the pump.

Axial Piston Pumps

An axial piston pump has a number of pistons (usually an odd number) arranged in a circular array within a housing which is commonly referred to as a cylinder block, rotor or barrel. This cylinder block is driven to rotate about its axis of symmetry by an integral shaft that is, more or less, aligned with the pumping pistons (usually parallel but not necessarily)

Internal lubrication of the pump is achieved by use of the operating fluid. Most hydraulic systems have a maximum operating temperature, limited by the fluid of about 120ºC (250ºF) so that using fluid as a lubricant brings its own problems. In this type of pump the leakage from the face between the cylinder housing and the body block is used to cool and lubricate the exterior of the rotating parts. The leakage is then carried off to the reservoir or to the inlet side of the pump again. Hydraulic fluid that has been used is always cooled and passed through micrometre sized filters before recirculating through the pump.

This type of pump can contain most of the necessary circuit controls integrally (the swash-plate angle control) to regulate flow and pressure, be very reliable and allow the rest of the hydraulic system to be very simple and inexpensive.

Radial Pumps

With a Radial piston pump the working pistons are in radial direction and symmetrically arranged around the drive shaft in contrast to the Axial piston pump. The stroke of each piston is caused by an eccentric drive shaft or an external eccentric tappet (I.E. Stroke ring)
These kind of piston pumps are characterized by the following advantages;

  • High efficiency.
  • High pressure (up to 1000 BAR)
  • Low flow and pressure ripple (due to the small dead volume in the workspace of the pumping piston)
  • Low noise level.
  • Very high load at lowest speed due to the hydrostatically balanced parts possible.
  • No axial internal forces at the drive shaft bearing.
  • High reliability.

Applications

Due to the hydrostatically balanced parts it’s possible to use the pump with various hydraulic fluids like mineral oil, biodegradable oil, HFA (oil in water), HFC (water-glycol), HFD (synthetic ester) or cutting emulsion. That implies the following main applications for a Radial piston pump;

  • Machine Tools (I.E. Displacement of cutting emulsion, supply for hydraulic equipment)
  • High Pressure Units (HPU) (I.E. Overload protection of presses)
  • Test Rigs
  • Automotive Sector (I.E. Automatic transmission, hydraulic suspension control)
  • Plastic and powder injection moulding
  • Wind energy

Centrifugal Pumps

Centrifugal pumps consist of a set of rotating vanes, enclosed within a housing or casing, used to impart energy to a fluid through centrifugal force. The pump has two main parts: a rotating element which includes an impeller and a shaft, and a stationary element made up of a casing (volute or solid), stuffing box, and bearings. Centrifugal pumps operate using kinetic energy to move fluid utilizing an impeller and a circular pump casing.

Centrifugal Pumps

Centrifugal pumps are used in many industries. Some of their most common applications/media transferred include: general purpose fluids, pure water, sludge and sewage, slurry, high viscosity fluids, power generation, the paper industry, the petroleum industry, chemicals and corrosives, gravel and solid materials, high temperature materials, and marine applications.

More typical applications for the centrifugal pumps are

  • Dewatering and Irrigation
  • Water and Chemical transfer
  • Dust suppression systems
  • Agricultural crop sprayers

Certain pumps are also suitable for acids and corrosive chemicals. Maximum flow rates up to 1180 LPM, max pressures up to 12 BAR, input speeds fro 540 – 6000 RPM.

Pump Configurations

  • Hydraulic motor driven
  • Petrol and diesel engine driven
  • Gearbox and electric motor driven
  • Pedestal and flange mounted

Available in various materials of construction to suit each product that requires pumping, including Stainless Steel, Hastelloy, Plastic, Cast Iron, Duplex, they can be controlled via pressure switches or pressure transducers. Standard products and  specialised products are available to suit all liquids and industries. With standard motors or to exact specification including ATEX. (EEXN – EEXE-EEXD)

Brands We Supply

We supply all brands of pumps to match specific duty requirements such as:

  • Apex
  • Azcue Pumps
  • Binda
  • Bombas Trief
  • Boyser
  • Calpeda
  • CAT Pumps
  • Debem
  • Dresser
  • Ebara
  • ESPA
  • Etatron
  • Flux
  • GemmeCotti
  • Grundfos
  • HCP
  • Ingersoll
  • Japy
  • Liverani
  • Lowara
  • Nova Rotors
  • Pedrollo
  • Raasm
  • Savino Barbera
  • Sero
  • Simpson
  • Standart Pompa
  • Tsurumi
  • TT
  • Worthington
  • Yildiz Pompa
Discover More

Click on the menu to the left to learn more about our different Hydraulic Pumps that we supply, repair and much more.

Fast Service

Get in touch today for a free quote and assessment of your requirements, we are on hand to help.