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Blackmer GNX3A Pump Skid, 3" Pump, Sliding Vane Positive Displacement, 15 hp Motor


Blackmer GNX3A Pump Skid, 3" Pump, Sliding Vane Positive Displacement, 15 hp Motor


GNX Pumps Brochure

IOM Manual

Parts List GNX3

Quick Specs:

  • Size:  3"
  • Model:  GNX3A
  • Manufacturer:  Blackmer
  • Type:  Rotary Vane, Sliding Vane, Positive Displacement
  • Flow Rate:  100-275 gpm
  • Motor:  15 HP
  • Max Working Pressure:  175 psi
  • BaseTek Composite Base Plate
  • Product String:  GNX3A/4/1R/C0/1/4/2/0/0/0/0/W/R0250-250TC/MT/871/RXXXX/B254TC/MTRB/XP981145


  • Alignment-free, reduced-speed pumps
  • Robust commercial-grade gear reducer with expanded ratio options
  • Eliminates traditional couplings
  • Retained rotor between bearing design extends mechanical seal life
  • Compact footprint utilizing close coupled, inline design
  • Alignment free design reduces downtime and simplifies maintenance
  • Flexible porting – 90° and 180° options
  • Corrosion resistant composite baseplate with pre-grouted build, flatness of 0.002” per foot, and 24 times increased vibration damping of steel
  • Advantages of sliding vane technology:
    • Unique sliding-vane pump design self-adjusts for wear to maintain flow rates
    • Excellent self-priming and dry-run capabilities
    • Sliding vane design provides sustained performance and trouble-free operation
    • Easy maintenance: vanes can be easily replaced without removing the pump from the piping system
    • High suction lift and line-stripping capabilities
    • Low maintenance and low life-cycle costs


Part of the Iron Line of sliding vane pumps, these Blackmer® pumps are the market’s only alignment-free, reduced-speed positive displacement pumps. They are suited for both portable and stationary applications. GNX Series pumps include the proven features of Blackmer legacy GX Series pumps but take them to the next level with the incorporation of a commercial-grade, single-stage gearbox. This innovative new gearbox fits between the motor and pump and is held in place by a permanent dowelled connection that creates a structural link between the high-speed and low-speed sides of the system. This results in a pump that will not need to be realigned either at initial installation or following a maintenance procedure, resulting in improved peace of mind for the operator. The pre-grouted GNX composite baseplate adds additional value to the pump, gearbox and motor setup by providing unmatched surface flatness, significant vibration damping, and reduced installation costs.

The GNX and GNXH Series pumps are designed to handle a wide range of non-corrosive, clean industrial liquids and petroleum products and are available in 2-, 2.5-, 3-, and 4-in sizes. The GNX Series pumps have a 90° porting orientation and the GNXH Series pumps have a 180° porting orientation.


  • Fuel Oils
  • Lube Oils
  • Jet Fuels
  • Gasoline
  • Edible Oils
  • Esters
  • Ketones
  • Naphthas
  • Ethers
  • Amines
  • Aromatics
  • Alcohols
  • Terpenes
  • Glycols

Ordering String:



Order Line Notes: Pump Model GNX3A Cast Iron, sliding vane pump with mechanical seals, integral relief valve, external ball bearings, and single-ended-spline shaft ready to accept a spool mounted gear reducer.

4 Vanes - Duravane®

1R SE Keyed Rot/Shaft, RH Rot

C0 IVCV Seal (Sta: Iron / FKM Rot: Carbon / FKM)

1 Standard Relief Valve

4 51-110 PSI STE RV Spring

2 FKM Elastomers

N 3" NPT Flange Cpscrws & Gskt

R0250-250TC SK871.1Z Reducer 2.50 ratio

250TC (1750/700 - 1450/580 rpm)

871 BasePlate for Pumps with 871 Reducer

B254TC BaseTek Baseplate, for Motor Frame 254TC

XP981145 15 HP 1800 rpm 60 Hz 3 ph 230/460

Volt 254TC FT Expl. Proof Motor