Three Screw Pump

Delta Corporation group is the pioneer in the field of Positive Displacement Rotary pumps since 1968. They introduced for the first time in India the concept of "Three Screw Pumps" in 1970's. Foreseeing the growing demand for totally reliable fuel and lube oil pumps for Thermal and Hydel Power Plants, Fertilizer, Chemical and Steel Projects a beginning was made by importing critical components and building pumps locally. Over decades, thousands of Three Screw pumps have been manufactured and delivered. Valuable experience was gained and modern manufacturing and testing facilities established under guidance from world-renowned European companies.

Over the years the market has grown considerably and the field of applications has become more diverse for these pumps, compelling innovations in the design and production of the pumps to answer the demands of the market.

In line with the current requirements, Delta is proud to present to this mature market, reliable, low noise, low vibration and low cost three screw pumps produced as per the latest state of the art manufacturing practices.

We have partnered with Settima Meccnaica s.r.l who are leading manufacturers of screw pumps in Europe since 1978.

Settima has focus on low noise, low pulsation pumps which help increase the overall efficiency and life of the pumps

Settima-Delta pumps are on the OEM list of major plant and equipment manufacturers, consulting organizations and has met with approvals from third party inspection agencies - national and international.

Working Principle

Settima-Delta Three Screw pumps employ just three screw elements - one power screw and two idler screws running in the three precision bores in the housing or liner. The screws are so profiled that they form a liquid tight seal between the thread. As the screws rotate, pockets/ cavities are formed where liquid gets trapped and conveyed from one end of the infinite stroke. This results in smooth, pulsation free flow with extremely low noise and vibration levels, almost impossible to be achieved by any other design of positive displacement or other types.

The power rotor does not drive the idlers as commonly believed. The hydraulic forces acting on screw flanks turn the idlers torquelessly thus reducing the friction. The idlers simply roll over the root diameter of idler dia.reduce the unit pressure, centralize the power rotor and absorb the radial loads. A balance piston integrally machined on power rotor takes care of axial thrusts.

While in operation, the screws are in hydrodynamic balance on film lubrication and do not require any additional bearings. The one ball bearing often used is only for axial positioning of rotor and safer operation of mechanical seals. Small rotor dimensions enable the pump to be operated at high speeds directly coupled 3000 or 3600 RPM motors or other prime movers. Such unique design and features has demonstrated excellent reliability with pumps in operation continuously non-stop for decades together without replacement of any components or maintenance on clean fluids.

Salient Features

High reliability High speed capability High speed capability
Long service life Insensitive to viscosities Insensitive to viscosities
Negligible maintenance High pressure capability High pressure capability
High efficiency Axial flow - no churning, chewing or shearing Axial flow - no churning, chewing or shearing
Self priming Excellent suction capability Excellent suction capability
Smooth pulsation free flow Hydraulic balancing of forces eliminates need for any bearings Hydraulic balancing of forces eliminates need for any bearings
Low noise and vibrations

Typical Applications

Fuel Oil Service:
Fuel oil burner service for Thermal Power Plant/ Industrial Package, Boilers, Furnaces, Kilns and Combustion systems.

Fuel transfer and booster service for Captive Diesel/ Gas Turbine Plants and Industrial Combustion Systems, Fuel Oil Circulations and Centrifuge Feeding. Tank farm tank to tank transfers.

Hydraulic Duties :
Hydraulic governing service for Water Turbines, Inlet Penstock Valves.

Low and medium pressure hydraulic applications, high pressure jacking oil service for rotor lifting for Turbines/ Compressors/ Alternators.

Lubricating Duty :
Pressure lubrication and cooling of bearings for Turbo Machinery, Gear Boxes, Bearing Lubrication of Coal Mills, ID/FD Fans, Diesel Engines, Steel Rolling Mills, Air pre-heater guide bearings, Compressors.

Seal Oil Service :
Hydrogen cooled Generators, Gas and Refrigeration Compressors.