G Type Single Screw Pump

The G type single screw pump is a positive displacement rotary pump based on the internal meshing principle. Its main working components are an eccentric screw rotor and a fixed stator. As the rotor turns inside the stator, sealed cavities are formed and move continuously from the suction end to the discharge end, pushing the medium forward smoothly and steadily.

Because the volume of each sealed cavity remains stable during transfer, the pump provides uniform flow and stable pressure with low internal flow velocity. This helps reduce vortex formation, agitation, and damage to the original structure of sensitive media.

The G type single screw pump is suitable for conveying high-viscosity media, liquids containing solid particles or fibers, and media that require continuous transfer with stable pressure. It is also suitable for applications where low agitation and low noise are required.

Features & Advantages

• Compact Structure: Few parts, small size, and convenient maintenance.
• Simple Wear-Part Design: The rotor and stator are the main wear parts and are easy to remove and replace.
• Handles Solids & Fibers: Suitable for media with high solid content, particles, or fibers.
• Uniform Flow: Provides stable flow and pressure, especially at low speed.
• Speed-Based Flow Control: Flow is proportional to pump speed, allowing convenient variable output control.
• Multiple Media Capability: One pump can handle media with different viscosities under suitable conditions.
• Flexible Installation: The pump can be installed at different inclined positions according to site requirements.
• Gentle Transfer: Suitable for sensitive materials that may be damaged by centrifugal force or strong agitation.

Working Principle

The G type single screw pump is an internally meshing rotary positive displacement pump. When the single-helical rotor performs planetary motion inside the double-helical stator bore, sealed cavities are continuously formed between the rotor and stator. These cavities move evenly from the suction end to the discharge end, transferring the medium at a constant volume.

This working principle makes the pump especially suitable for high-viscosity media, particle-containing media, fiber-containing media, and applications requiring continuous delivery without the periodic pressure fluctuation commonly associated with reciprocating pumps.

Typical Applications

The G type single screw pump is widely used in environmental protection, shipbuilding, petroleum, pharmaceutical, daily chemical, canned food, brewing, construction, printing, paper, metallurgy, dyeing, chemical, fertilizer, and related industrial sectors.

Typical applications include:

• Environmental protection and wastewater treatment
• Marine and shipbuilding systems
• Petroleum and chemical processing
• Pharmaceutical and daily chemical production
• Food, canned food, and brewing processes
• Paper, printing, and dyeing systems
• Construction and industrial slurry transfer
• Fertilizer and related chemical production

Suitable Media

The G type single screw pump is suitable for:

• High-viscosity liquids
• Media containing solid particles
• Fiber-containing liquids
• Shear-sensitive materials
• Suspensions and slurry-like media
• Liquids requiring stable flow and low agitation

According to the source material, viscosity suitability varies by pump size and may range from 20000 mPa·s to 200000 mPa·s. The pump can handle particles up to 16 mm in diameter, provided the particle size does not exceed the rotor eccentricity. Fiber length can reach up to 100 mm, approximately 0.4 times the rotor pitch. General solid content can reach 40%, and fine powder-like solids may reach 60% or higher under suitable conditions.

Operation Notes

Before starting the pump, confirm the correct rotation direction. Reverse rotation should be avoided unless the system is designed for it.

The pump must not run dry without medium, as this may damage the stator. For a newly installed pump, or a pump that has been stopped for several days, add a suitable amount of oil into the pump body first and rotate the pump manually several turns before startup.

After conveying high-viscosity, particle-containing, or corrosive media, the pump should be flushed with water or solvent to prevent blockage and make the next startup easier. In winter, residual liquid should be drained to prevent freezing damage.

During operation, lubricating oil should be added regularly to the bearing housing. If leakage is found at the shaft end, the oil seal should be checked and replaced when necessary. If abnormal operating conditions occur, stop the pump immediately, inspect the cause, and remove the fault before restarting.

Technical Parameters