Our Helical External Gear Pump is designed for medium and high-pressure transfer applications, with versatile uses in industrial settings. This pump features a horizontal shaft that transmits circular movement to the opposite gear. As the gears separate, liquid is drawn in to fill the space between them. When the gears move closer together, this liquid is moved with a rotary motion towards the pump outlet. With a capacity for pressures up to 20 Bar (depending on the liquid viscosity), this pump excels in situations requiring uninterrupted flow for less viscous and medium-pressure applications. Additionally, these pumps are ATEX-available for use in hazardous environments.
Typical applications for our Helical External Gear Pump:
Overview
Features & Benefits
Specifications
How does a Helical External Gear Pump work?
The pump features a horizontal shaft, 180° port position and has 2 external helical gears.
The pump shaft operates, moving the gears which draws liquid into the port. The liquid fills the space between the gears and moves towards the outlet of the pump as the shafts turn.
By-Pass/Pressure Relief Valve Operation:
The intended purpose of a By-Pass or Pressure Relief Valve (PRV) is to ensure that the pump and drive unit are protected from unnecessary damage that may be incurred during over-pressurisation which is mainly caused by closed valve operation or blockages in the discharge line. By-Passes can be either installed on the pipework and route fluid back to the suction of the pump or tank, in the form of a By-Pass Circuit, or indeed installed directly on the pump head, as detailed below.
The By-Pass, when opened, relieves excess fluid and pressure from the discharge section of the pump to the suction side and effectively allow the pump to recirculate within itself until the blockage in the line has been cleared or closed valve opened to allow the process medium to carry on through the system and drop the pressure in the line to an acceptable level for the installed equipment.
As By-Passes are spring-loaded and adjustable, they can be tweaked in situ to cater for changing system or pump requirements.
The Helical Gear Pump Range has a compact robust design with many beneficial features including:
- Shaft support on both sides of the gears
- Pressures up to 300 meters
- Wide speed range, up to 50-1500 rpm
- Often used as lubrication pumps in machine tools, in fluid power transfer units, and as oil pumps in engines.
- Precise transfer and metering applications involving polymers, fuels, and chemical additives.
- Can be fitted with Heating Jackets to maintain fluid temperature
- By-Pass/Pressure Relief Valve can be installed to protect the pump from over-pressurisation
| Max Capacity (m³/hr) |
250m³/hr |
| Max Pressure (m) |
150m |
| Viscosity (cSt) |
up to 55,000 cSt |
| Max Speed (rpm) |
1500 rpm |
| Max Temperature (°C) |
350°C |
| Materials & Limits |
| Connection Sizes |
2” – 10” |
| Capacity Range |
1 – 320 m³/hr |
| Pressure Range |
10 – 150m |
| Temperature Range |
up to 350ºC |
| Speed Range |
50 – 1500 rpm |
| Viscosity Range |
20 – 55,000 cSt |
| Pump Body & Cover |
Cast Iron, Ductile Cast Iron, Cast Steel, Stainless Steel AISI 304/316 |
| Gears |
Cast Iron, Ductile Cast Iron, Cast Steel, Stainless Steel AISI 304/316 |
| Bearings |
SnBz12 Bronze, Carbon Graphite, Ina Bushing Bearings |
| Sealing |
Soft Seal / Packed Gland, Mechanical Seal |
Sizes Available:
| Model |
Max Capacity (m³/hr) |
Max Pressure (Bar) |
Viscosity Range (cSt) |
Max Speed (rpm) |
Max Temperature (°C) |
| YHL 2 |
12 |
10 |
10 – 550 |
900 |
200 |
| YHL 2½ |
38 |
15 |
10 – 55000 |
450 |
350 |
| YHL 3 |
38 |
15 |
10 – 55000 |
450 |
350 |
| YHL 4 |
76 |
15 |
10 – 55000 |
450 |
200 |
| YHL 8 |
250 |
15 |
10 – 55000 |
450 |
200 |
| YHL 10 |
250 |
15 |
10 – 55000 |
450 |
200 |
