BSM Brown & Sharpe No. 557 Foot Mounted Rotary Gear Pump

BSM Brown & Sharpe No. 557 Foot Mounted Rotary Gear Pump

BSM Brown & Sharpe No. 557 Foot Mounted Rotary Gear Pump is a rugged, positive displacement external gear pump for continuous industrial and maritime fluid transfer services. This unit is one of the distinguished BSM 500-Series and is precision machined for clean, lubricating liquids including hydraulic oils, heavy lubricants, fuel oils and synthetic viscous media. No. 557 has a rugged cast iron casing, heat treated alloy steel precision gears and a stiff foot mounted design. When working under high duty cycles the No. 557 offers excellent volumetric efficiency and long term pressure stability.

Model Details:

• Brand: BSM
• Product Category: Industrial Rotary Gear Pumps / Positive Displacement Pumps
• Series: 500-Series Heavy Duty
• Model: No. 557
• MPN: BSM-557-FT
• Mounting Style: Foot Mounted (Base/Floor Mount)

Positive Displacement External Rotary Gear Pump – Specifications

Main features

1. Precision Construction: Metal-to-metal joints are precision honed to retain tight original tolerances without the need of ordinary gaskets that can leak during temperature expansion.
2. High Pressure Capability – Designed for sustained working pressures to 500 PSI at normal motor speeds.
3. Rigid Foot Mounting – Heavy-duty mounting feet included into the baseplate provide stable baseplate or direct structural bolting without the need for complex intermediate adaptor brackets.
4. Self-Lubricating Operation: Internal journal and bearing lubrication is provided by the pumped media, reducing supplementary maintenance requirements.

Applications

• Marine fuel oil transfer, lube oil priming, and engine room auxiliary services.
• Industrial hydraulic power units on heavy machine tools and stamping presses.
• Oil field gathering lines, secondary recovery systems, and lease automatic custody transfer (LACT) units.
• High-viscosity chemical additive distribution and petroleum product blending plants.

Compatibility

• Compatible Prime Movers: NEMA C-Face and foot-mounted electric motors via flexible couplings, gear reducers (GR-Drive), or V-belt (B-Drive) configurations.
• Interchangeable Series: Direct footprint and performance upgrade path within the BSM 500-Series lineup (Models 537, 547, 557, 567).
• Service Kits: Fully compatible with BSM standard repair kits, replacement heat-treated gear sets, and sleeve/bearing overhaul packages.

Marine Engineer Expert’s Guide

1. Alignment Precision: When coupling the No. 557 to an electric motor on a shared baseplate, ensure dial indicator alignment reads within 0.002 inches TIR (Total Indicator Reading). Angular or parallel misalignment will induce premature wear on the internal sleeve bearings and shaft packing gland.
2. Suction Line Design: Keep suction piping at least one size larger than the pump port (minimum 1.25 inches to 1.5 inches) with a short, direct run. Restrictive suction lines invite cavitation, which degrades flow output and pits the precision-machined gear teeth.
3. Cold Starts & Viscosity Management: If pumping heavy lube oils or residual fuels in cold engine-room environments, ensure fluid viscosity is pre-heated within the recommended 100 SSU to 1,000 SSU operating window to prevent excessive torque spike and motor overload during initial startup.

Frequently Asked Questions

What is the maximum pressure rating of the BSM No. 557 rotary gear pump?

Depending on the operating speed (RPM) and the viscosity of the fluid being pumped, the BSM No. 557 is capable of operating at continuous discharge pressures up to 500 PSI.

Does the No. 557 pump require gaskets to seal the casing joints?

No. BSM 500-Series pumps use precision-ground joints rather than conventional paper or composite gaskets. This engineering design holds tight tolerances on internal operation, making routine maintenance teardowns easier.

Can this pump run safely with non-lubricating fluids?

The pumped liquid is then used for internal lubrication of the sleeve bearings of the standard BSM No. 557. For non-lubricating or volatile liquids, consult with unique material combinations with carbon-graphite or bronze bearings and custom mechanical seals.

What size is the normal port connection on the Brown & Sharpe No. 557?

The pump has 1.0” port connections for industrial piping and high integrity flange or threaded adapters.