GR60 SMT 500L Parker Three-Screw Pump 80 Bar

Model Number	GR60 SMT 500L

Product Description

Product Overview

The GR60 SMT 500L is a large-flow Parker GR Series three-screw pump designed for industrial and marine fluid-transfer applications.

According to Parker’s official GR Screw Pump catalogue, the GR60 frame is available in 440 L/min and 500 L/min configurations, with nominal flow specified at 2950 rpm. The SMT designation represents the dry-installation 80-bar series, while SMIT refers to the submerged version. The SMT range is rated for 80 bar continuous pressure and 100 bar intermittent pressure, with a shaft-speed range of 500–3600 rpm.

Unlike a conventional external gear pump, the GR design uses a three-screw axial-flow pumping principle. The two secondary screws are hydraulically driven by the pumped fluid, while the rolling interaction between the screws reduces mechanical noise and vibration. Parker positions the GR series for lubrication, cooling, seal-oil, power-hydraulic and fluid-transfer applications.

For replacement projects, the complete pump configuration should be verified, including shaft, flange, ports, rotation, sealing system and installation arrangement.

Technical Specifications

Manufacturer: Parker Hannifin
Series: GR Series
Product Type: Three-Screw Pump
Frame Size: GR60
Configuration: SMT 500L
Installation: Dry
Nominal Flow: 500 L/min at 2950 rpm
Continuous Outlet Pressure: 80 bar
Intermittent Outlet Pressure: 100 bar
Speed Range: 500–3600 rpm
Inlet Pressure: -0.7 to 3 bar
Standard Rotation: Clockwise viewed from the shaft end
Optional Rotation: Counter-clockwise
Viscosity Range: 4–2000 mm²/s
Seal Options: NBR, VITON/FKM, EPDM
Standard Housing: Extruded aluminium alloy
Special Housing: Carbon steel or cast iron; stainless steel on request
Main Screw: Steel
Secondary Screws: Cast iron
Ambient Temperature: -20°C to +60°C
Fluid Temperature: -20°C to +180°C
Cleanliness Reference: NAS 1638 Class 10 or ISO DIS 4406 19/16
Recommended Filtration: β25 > 75
Maintenance: No routine maintenance specified for the basic catalogue configuration
Approx. Dry GR60 Weight: 25 kg
GR60 Mounting Flange: B160 / E18 / F200 / d1 235 mm
GR60 Shaft Reference: A55 / D32 / T35 / U10 mm
GR60 500L Suction Port: 3″ SAE
GR60 500L Pressure Port: 2½” SAE

500 L/min Performance Interpretation

The 500 L/min designation is a nominal configuration value at 2950 rpm, not a fixed flow guarantee at every pressure and viscosity condition.

Parker’s official 80-bar performance data show that, at 2950 rpm, the GR60 500L configuration produces different actual flow depending on fluid viscosity and working pressure.

Examples include:

6 cSt: approximately 528 L/min at 10 bar, 509 L/min at 20 bar, 494 L/min at 30 bar, 482 L/min at 40 bar and 471 L/min at 50 bar.
68 cSt: approximately 540 L/min at 10 bar, 527 L/min at 20 bar, 516 L/min at 30 bar, 507 L/min at 40 bar, 500 L/min at 50 bar and 482 L/min at 80 bar.
400 cSt: approximately 547 L/min at 10 bar and around 502 L/min at 80 bar.

Actual system flow should therefore be selected from the pressure/speed/viscosity performance curves rather than from the nominal 500 L/min label alone.

Key Technical Advantages

Three-Screw Axial-Flow Architecture

The GR pump uses one main screw and two hydraulically driven secondary screws. Parker states that the three-moving-part design and rolling interaction between the screws contribute to low pulsation, low noise and low vibration.

High-Flow GR60 Platform

The GR60 frame supports 440 L/min and 500 L/min configurations at the catalogue reference speed of 2950 rpm. The 500L version is therefore suited to large-volume lubrication, cooling and fluid-circulation systems.

80-Bar Continuous Pressure Capability

The SMT version belongs to Parker’s 80-bar family, with 80 bar continuous and 100 bar intermittent pressure ratings. It should not be confused with the SMT16B 40-bar version.

Aluminium Housing with Heavy-Duty Material Options

The standard GR housing is manufactured from extruded aluminium alloy, while carbon steel and cast iron options are available for special applications. The main screw is steel and the secondary screws are cast iron.

Broad Fluid Viscosity Capability

The catalogue specifies a general viscosity range of 4–2000 mm²/s and provides performance data for different viscosity conditions. This makes the platform suitable for a wide variety of lubrication, cooling and fluid-transfer duties.

Multiple Installation and Interface Options

The GR family supports multiple motor-interface, shaft, flange, sealing and port configurations. This makes complete configuration matching particularly important for aftermarket replacement and retrofit applications.

Application Areas

Typical Parker GR applications include:

Industrial lubrication systems
Diesel engine lubrication
Gas turbines
Compressors
Gearboxes and gear lubrication
Seal-oil systems
Power hydraulics
Machine tools
Injection molding machinery
Hydraulic winches
Variable-pitch propeller systems
Cooling systems
Oil & gas equipment
Refinery and petrochemical systems
Fuel-oil transfer systems
Marine fluid-transfer applications

Expert Maintenance Tips

Verify Dry vs. Submerged Installation

SMT is the dry version, while SMIT is the submerged version. This distinction must be confirmed before replacement or retrofit work.

Prevent Shaft Misalignment

Parker specifies that the pump drive should not introduce unwanted axial or radial shaft loads. Proper shaft alignment and an appropriate flexible coupling are therefore essential.

Keep the Suction Circuit Low-Restriction

The GR60 500L configuration moves a very high volume of fluid. The suction line should therefore be adequately sized and designed to minimize pressure drop, air ingestion and cavitation risk.

Maintain Hydraulic Fluid Cleanliness

The catalogue references NAS 1638 Class 10 / ISO DIS 4406 19/16 cleanliness and recommends filtration with β25 > 75. For a 500 L/min system, filter element surface area and pressure drop should be checked together with filtration efficiency.

Match Performance to Viscosity

Actual output changes with fluid viscosity, working pressure and speed. Parker’s GR60 performance curves should be used for final system sizing rather than treating 500 L/min as an invariant operating flow.

Do Not Use 100 Bar as a Continuous Setpoint

The 80-bar rating is the continuous pressure rating, while 100 bar is the intermittent rating. Continuous system operation should therefore be engineered around the 80-bar limit.