BM3 Shaft Distribution Orbital Hydraulic Motor

BM3 Shaft Distribution Orbital Hydraulic Motor

The BM3 hydraulic motor is a shaft distribution gerotor roller stator LSHT motor offered in seven displacements: BM3-100, BM3-125, BM3-160, BM3-200, BM3-250, BM3-315 and BM3-400. The catalogue version uses shaft distribution through the output shaft.

All values on this page come from the printed BM3 catalogue, pages 33–35. Olive Branch Hydraulics manufactures orbital motors and hydraulic pumps in Hebei, China, and quotes EXW Hebei.

• Typical applications: oil machinery, coal machinery and small lifting machinery. Confirm the actual load and installation before selecting a displacement.
• Also listed as: BM 3, BM-3, BM3 100, BM3 125, BM3 160, BM3 200, BM3 250, BM3 315, BM3 400; motor hidráulico BM3; moteur hydraulique BM3; гидромотор BM3.
• Images: product photos show BM3 series construction and do not identify a specific displacement.

Key Features

• Shaft distribution valving: commutation runs through the output shaft. This is the BM3 catalogue construction and should not be confused with disc-valve orbital motors.
• Gerotor roller stator: the roller set forms the displacement chambers. Seven nominal displacement options cover 100, 125, 160, 200, 250, 315 and 400 cc/rev.
• Standard flange drawings, both 120 mm square: F1 has four Ø13 mm holes, a Ø100 mm pilot and a Ø127 mm bolt circle. F2 has eight Ø11 mm holes and a Ø85 mm pilot.
• Port option P1: A/B M22×1.5 and drain M14×1.5. Port spacing is 46 mm, and the distance from the mounting face to the A-port centre is 62.5 mm.
• Port options P2 / P3: A/B 2×M18×1.5 and drain M14×1.5, on different plate patterns. Check the drawing as well as the thread.
• Six shaft ends: keyed Ø25, Ø30 and Ø32 mm shafts, plus three metric rectangular splines (6D30×26×8, 6D30×26×6, 6D25×21.5×6).
• Rotation: the standard direction is clockwise when facing the shaft, with oil in at port A and out at port B.

BM3 Orbital Motor Technical Specifications

Pick the displacement against required output torque and shaft speed first. Flow is 50 LPM continuous and 60 LPM intermittent for every displacement.

The figures are catalogue maximums. They are not a simultaneous operating point, so confirm duty cycle and intermittent limits for your application. H1 and H change with displacement, so check the installation envelope against the drawing.

BM3 Model Codes and Configuration Checks

Every BM3 order is built to its own ordering code: BM3 – displacement – flange – shaft – port – rotation – option. We quote against that code and the matching catalogue drawing, not against a cross-reference number.

1. Send the requirement: nameplate photo, drawing, pressure, flow, shaft and ports.
2. We check the drawing for flange holes, port plate pattern and shaft end.
3. We confirm the configuration and quote EXW Hebei.
4. State any sample or fit-test requirement in the RFQ; availability and terms require confirmation.
5. Production follows the approved configuration, and the order ships EXW Hebei.

• Distributors and wholesale buyers: include annual demand, order quantities and the model mix for a configuration-specific quotation.
• OEM and private label: nameplate marking and packaging requirements are reviewed alongside the drawing at RFQ stage.
• Project and end users: configuration is checked against your load and installation data before the order is released.

Shaft Dimensions and Ordering References

The catalogue ordering fields are BM3 / nominal displacement / flange / shaft / port / rotation / option. Standard installation drawings show F1 and F2; the ordering chart also lists hole-pattern alternatives, so approve the actual flange drawing rather than relying on the flange code alone.

No numeric OEM cross-reference is assigned solely from the BM3 family name. For replacement enquiries, send the original manufacturer, full part or material number, equipment model and motor photographs; dimensional and operating checks determine the quoted configuration.

FAQ

Is the BM3 a disc valve motor?

This catalogue BM3 uses shaft distribution. Check the drawing when another manufacturer uses the same BM3 name for a different motor design.

Is the BM3 a direct replacement for Danfoss OMS or OMR motors?

Not automatically. Replacing any original or OEM part number requires checking the nameplate and the drawing, including flange, shaft, ports and length.

Can maximum pressure, speed and torque be reached at the same time?

No. Each value is a separate catalogue limit, so send your duty cycle for confirmation.

Are the A2, A5 and A6 splines SAE 6B?

No. They are metric rectangular splines: 6D30×26×8 (A2, M14 end), 6D30×26×6 (A5) and 6D25×21.5×6 (A6). A5 and A6 both have M8 ends.

Do P2/P3 ports interchange with P1?

Not by thread alone. The plate patterns differ, so compare the port drawings.

Are F1 and F2 flanges interchangeable?

No. Both are 120 mm square, but the hole count, hole size and pilot differ, and some hole combinations require drawing confirmation.

Is BM3.5 part of this series?

No. BM3.5 is a separate series and should be quoted separately.

Call To Action

For an EXW Hebei quotation, send us the quantity, destination, a nameplate photo or drawing, working pressure and flow, the required shaft (A1–A6) and the port option (P1–P3). Add your rotation and flange choice, and we will return a configuration check together with the price.