Blackmer Technology

Your Pump Questions Answered

Get in-depth information about Blackmer pump and compressor technologies while learning why our solutions are the ideal choice to help solve your most critical fluid-handling applications.

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Blackmer Products

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Blackmer® is the leading global provider of innovative, high-quality sliding vane, centrifugal, screw and regenerative turbine pump, and reciprocating gas compressor technologies for the safe transfer of liquids and gases.

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Sliding Vane Pumps

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Blackmer Markets

Providing Innovative Product-Transfer Solutions for a Variety of Markets and Applications

Blackmer provides innovative product transfer solutions for many markets and applications, including in the chemical process, energy, transport, military & marine; general industrial, and oil & gas industries.

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Blackmer HRB HRB-GX Bracket 600 Gear Reducers Blackmer HRA HRA-GX Bracket 600 Gear Reducers Blackmer HROF HRO-GX Bracket 600 Gear Reducers

Gear Reducers

Blackmer® helical gear reducers are designed for use with 1,750, 1,150, 1,450, and 950 rpm motors up to 30 hp. A full range of standard reduction ratios are available from 2.24:1 to 9.08:1 to provide standard operation speeds for Blackmer pumps as well as other brands of positive displacement pumps.

Blackmer gear reducers are rated in accordance with practices of ANSI/AGMA 6010. They are manufactured in three sizes (HROF, HRA, and HRB) to accommodate a variety of pump speeds for low to high-viscosity transfer applications.

Gear reducers are available fixed bracket mounted (HROF), or adjustable bracket mounted versions (HRA and HRB) for fast, accurate alignment of pumps/reducers and prime movers.

Features and Benefits

Blackmer gear reducers are constructed on hardened, heat-treated, precision helical gears and pinions to provide years of trouble-free operation. For smooth, quiet running, the gears and pinions are immersed in oil, while shafts are supported at both ends by large ball bearings for added strength and reliability.


Model Reduction Ratios
HROF 2.24, 2.72, 3.32, 4.10, 4.94
HRA 2.24, 2.76, 3.40, 4.19, 5.06, 6.27, 7.65
HRB 2.70, 3.52, 4.36, 5.77, 7.71, 9.18