Screw Pump
Description
The G-type screw pump is an internally meshed, fully enclosed screw pump that falls under the category of rotary positive displacement pumps. With excellent adaptability to various media, smooth and continuous flow, strong suction capability, and extremely low pressure pulsation, this pump can efficiently handle:
Free-flowing liquids
Highly viscous fluids
Media containing hard suspended or solid particles
Fibrous materials
Its wide operating range, adjustable flow, and high efficiency make it suitable for diverse industrial applications.
As a result, G-type screw pumps are widely used across industries such as environmental protection, marine, petroleum, pharmaceuticals, daily chemicals, food processing, brewing, construction, mining, chemical engineering, printing, papermaking, power plants, and boiler systems.
Types of G-Type Screw Pumps
G-type screw pumps are generally classified into:
1. Single-Screw Pumps
2. Twin-Screw Pumps
Single-Screw Pump Structure & Working Principle
The primary working components of a single-screw pump include:
The eccentric screw (rotor)
The fixed bushing (stator)
Due to the unique geometric pairing of the rotor and stator, a series of independent, sealed conveying chambers are formed. As the rotor rotates, the chambers move continuously in the axial direction, delivering the medium at a constant volume and stable pressure—without inducing turbulence or agitation.
Key Features
Adjustable flow by varying pump speed
Capable of operating at both high and low speeds
Discharge pressure increases with the number of stages
Each stage adds approx. 0.6 MPa
Common pressure ratings: 0.6 MPa, 1.2 MPa, 1.8 MPa
Because the stator is made of special elastic materials, the single-screw pump is especially suitable for:
High-viscosity media
Fluids containing hard suspended particles
Liquids with short fibers
Working principle
The working principle of a single-screw pump: When the single-threaded helical rotor performs planetary motion around the stator axis inside the double-threaded helical stator hole, the sealed cavities formed between the rotor-stator pair continuously, uniformly, and at a constant volume transport the medium from the suction end to the discharge end.
Characteristic
Self-priming performance is excellent, with stable flow and minimal pulsation/shear.
It handles a wide range of fluid viscosities and can even convey media that lack self-flow capability. It is also insensitive to liquid impurities.
The simple structure ensures high operational efficiency, long service life of rotating parts, minimal wear, and easy maintenance and replacement.
The inlet direction can be adjusted.
Application
Environmental Protection: Transportation of industrial wastewater, domestic sewage, and sludge or turbid water containing solid particles and short fibers; particularly suitable for equipment such as oil-water separators and plate-and-frame filter presses.
Shipbuilding Industry: Handling of bilge cleaning, oil-water mixtures, oil residues, oily wastewater, and other media.
Petroleum Industry: Transporting crude oil, mixtures of crude oil and water, mixtures of coalbed methane and water, and polymer injection into reservoirs, thereby reducing the cost of mechanical oil extraction and coalbed methane recovery while increasing oilfield recovery rates.
Pharmaceutical and Daily Chemical Industries: Conveying various viscous pastes, emulsions, and creams, including cosmetics.
Food and Canning Industry: Transporting various viscous starches, oils, honey, syrups, fruit purees, cream, fish and meat pastes, and their by-products.
Brewing Industry: Handling various fermented thick slurries, dense distiller’s grains, food product residues, various sauces, pastes, and viscous liquids containing solid particles.
Construction Industry: Spraying and conveying cement mortar, lime slurry, coatings, and other paste-like materials.
Mining Industry: Pumping groundwater and slurry containing solid particles from mines to the surface.
Chemical Industry: Transporting various suspensions, greases, solid pastes, and adhesives.
Printing and Paper Industry: Conveying high-viscosity inks, PVC polymer pastes for wallpaper, and pulp of various concentrations and short-fiber stock.
Industrial Boilers and Power Plants: Transporting coal-water slurry.
