Roper Pump 2AM27 A-Series Hydraulic Gear Pump

Roper 2AM27 A-Series Hydraulic Rotary Gear Pump

The Roper Pump Company 2AM27 is a positive-displacement external helical gear pump engineered for continuous-duty transfer, pressure-feed lubrication, and low-pressure hydraulic service. Operating with a theoretical displacement of 0.027 gallons per revolution (2.7 gallons per 100 revolutions), this unit delivers up to 48.6 GPM at standard 1,800 RPM motor speeds with an operating envelope rated up to 150 PSI.

The 2AM27 configuration addresses the mechanical failure modes common to fluid circulation skids: fluid pulsations, shaft deflection, and premature journal wear. Built with precision-machined ductile iron helical gears within a high-tensile cast iron housing, fluid unloads smoothly across the gear teeth rather than slamming in trapped pockets, which minimizes hydraulic chatter and airborne decibel levels. Hydrostatically and operationally pressure-tested on test benches, each unit verifies zero casing weepage, correct internal pressure relief cracking tolerances, and positive displacement volume against targeted backpressure.

Model Details:

• Manufacturer: Roper Pump Company
• Series: A-Series Rotary Gear Pumps
• Model: 2AM27
• Manufacturer Part Number (MPN): 2AM27 / 2AM27-1A
• Motion Industries SKU Ref: MI #00868781
• Harmonized Tariff Code (HTS): 8413.91.9096 / 8413.60.0030

Technical Details

Part Number Cross-References

• Roper 1AM27: Bare-shaft pedestal mount equivalent, mechanical seal, without integral relief valve (uses inline relief system).
• Roper 2AP27: Packed box shaft seal configuration with integral relief valve (for heavy crude/tar service).
• Roper 18AM27: Direct motor-mount bracket adaptation with internal relief valve and mechanical seal.
• Roper 17AM27: Direct motor-mount bracket adaptation, mechanical seal, less internal relief valve.
• Viking Pump Alternative: Viking G-475 / G-4195 series equivalent porting/flow profile (requires check of foundation hole footprint and centerline height).

Compatibility

• Prime Movers: Directly coupled to NEMA 184T / 213T / 215T electric C-face or foot-mount motors (1,150–1,750 RPM) via elastomeric jaw couplings (Lovejoy, TB Wood’s Sure-Flex).
• Engine-Drive Skids: PTO shaft outputs from auxiliary diesel engines (Caterpillar 3406/C9, Cummins QSL9/6BT, Detroit Diesel 6-71 auxiliary drive stations).
• Purifier & Filtration Skids: Alfa Laval, Westfalia, and GEA lube oil conditioning and fuel treatment separators.
• Deck Equipment: Winch and anchor windlass closed-loop auxiliary boost feeds; steering gear replenish circuits.

Frequently Asked Questions

What does “2AM27” designate in the Roper A-Series numbering code?

The designation breaks down as: 2 indicates foot-mounted assembly with an integrated internal relief valve; A specifies Roper’s A-Series helical gear hydraulic product line; M designates a mechanical face seal construction (as opposed to “P” for packed gland); and 27 designates the displacement sizing of 0.027 gallons per shaft revolution (2.7 gal/100 rev) with 2-inch standard NPT ports.

Can the Roper 2AM27 pump handle variable viscosity fluids like heavy marine diesel and lube oil?

Yes. The positive displacement helical gear action handles a broad range from 30 SSU light distillate fuels up to 2,500 SSU lubricating oils at standard electric motor speeds (1,800 RPM). When moving viscosities exceeding 2,500 SSU (up to 100,000 SSU), pump rotation speed should be reduced via gear reducer or VFD to 300–600 RPM to keep suction lines fully flooded and avoid cavitation.

Is the internal relief valve suitable for continuous bypass throttling?

No. The built-in relief valve is an emergency safety bypass intended solely to prevent casing overpressure when downstream lines are abruptly isolated or valves are shut. Running the pump continuously over its internal relief valve rapidly heats the localized trapped oil, degrading fluid lubricity, scorching the bronze journal bearings, and thermal-shocking mechanical seal faces. For continuous bypass loops, install an external relief line routed back to the main supply storage tank.

How do I reverse the flow direction on the Roper 2AM27 pump?

The pump supports bi-directional operation. However, because the unit includes an integral relief valve, you must physically disassemble and rotate the relief valve housing by 180 degrees so that the bypass flows from the new discharge chamber back into the new suction chamber. Never reverse rotation without adjusting the relief valve cap position.

What are the operational signs that the internal bronze bushings require replacement?

The earliest indicators of bushing wear are a progressive drop in discharge pressure, an increase in motor amperage at identical operating viscosity, and an audible change from a clean hum to a grinding whine. This indicates that radial clearance on the gear tips has widened, allowing high internal slip (recirculation). Inspect the bearings and replace them before the rotor tooth crests contact the cast iron pump housing cavity walls.