Products & Services

Mechanical Pumps are at the Heart of our Expertise

Mechanical pumps serve in a wide range of applications, such as in the energy industry for pumping oil and natural gas or operating cooling towers in geothermal operations. Water districts are another market where Delta Pump has significant experience. We focus on two types of mechanical pumps: centrifugal and positive displacement.



Property Centrifugal Positive Displacement
Effective viscosity range Efficiency decreases with increasing viscosity (max. 200Cp) Efficiency increases with increasing viscosity
Pressure tolerance Flow varies with changing pressure
Efficiency decreases at both higher and lower pressures
Flow insensitive to changing pressure
Efficiency increases with increasing pressure
Flow (at constant pressure) Constant Pulsing
Shearing (separation of emulsions, slurries, biologican fluids, food stuffs) High speed motor damages shear-sensitive mediums Low internal velocity.Ideal for pumping shear sensitive fluids

Centrifugal Pumps for High Flow Rates

Centrifugal pumps are used to transport fluids by converting rotational kinetic energy to hydrodynamic energy. The fluid enters the pump impeller along or near to the rotating axis. It is accelerated by the impeller, flowing radially outward into a diffuser or volute chamber (casing), then exits the system.

They are commonly used for water, sewage, agriculture, petroleum, and petrochemical pumping. Centrifugal pumps are often chosen for their high flow rate capabilities, abrasive solution compatibility, mixing potential, as well as their relatively simple engineering.

Positive Displacement Pumps for Pumping High Viscosity Fluids

A positive-displacement pump moves a fluid by trapping a fixed amount and forcing (displacing) that trapped volume into a discharge pipe.

Liquid flows into the pump as the cavity on the suction side expands. The fluid flows out of the discharge as the cavity collapses. The volume is constant through each cycle of operation.


Type of PD Pump Application Features
Piston pump
Plunger pump
Water –high pressure washing; other low viscosity liquids; oil production; paint spraying
Reciprocating action with piston(s) sealed with O-rings
Reciprocating action with plunger(s) sealed with packing
Diaphragm pump Used for metering or dispensing; spraying/cleaning, water treatment; paints, oils; corrosive liquids Sealless, self-priming, low flows and capable of high pressures
Gear pump Pumping high viscosity fluids in petrochemical, chemical and food industries: oil, paints, foodstuffs Meshed gears provide rotary pumping action
Lobe pump Chemical and food industries; sanitary, pharmaceutical, and biotechnology applications Low shear and wear. Easy to clean or sterilize
Screw pump Oil production, fuel transfer and injection; irrigation Fluid moves axially reducing turbulence; capable of high flow rates
Vane pump Low viscosity fluids; automotive transmission systems; fuel loading and transmission; drinks dispensers Resistant to entrained solids and withstands vane wear. Design allows variable output