A6VM and A6V Series Motor Rotary Groups and Spare Parts
A6VM and A6V variable displacement motor rotary groups and spare parts in sizes 28 to 1000 for travel and drum drives.
Product Overview
A6VM is the variable displacement bent axis motor used on travel drives, drum drives and winches where the machine needs both high torque at low speed and a fast travel range. Because the motor changes angle in service, the block face and the control both wear. We machine rotary groups, blocks, piston sets, valve plates and piston rings for sizes 28 to 1000.
| A6VM | 28 56 63 80 107 160 200 250 355 500 |
|---|---|
| A6V | 28 55 80 107 125 160 200 250 355 500 1000 |
Key Benefits
- Supplied as a matched set so the block, shoes and valve plate run in together
- Same envelope and spline as the original, so the pump goes back on the machine unchanged
- Available for frames the original maker has moved off its list
- Twelve month warranty on the same terms as a new original part
Application Scenarios
- Travel drives on tracked and wheeled machines
- Drum and mixer drives
- Winch drives on cranes and deck equipment
- Test rigs needing a wide speed range
Who It Is For
- Pump rebuild shops working to a customer deadline
- Plant and fleet maintenance teams
- Distributors carrying rotary group stock for local machines
- Machine builders needing a second source
Problems It Solves
- The machine will not reach full travel speed
- Torque has dropped and the machine stalls on a slope
- The motor runs hot and the case drain flow is high
- The control no longer swings the motor through its full range
Technical Features
- Cylinder block with sintered bronze running face bonded and machined after sintering
- Piston and shoe assemblies swaged and checked for shoe clearance
- Valve plate lapped to a mirror finish so the pair seals under pressure
- Retainer plate and ball guide matched to the block
- Splines and bearing seats ground after heat treatment
Specifications
Performance figures depend on the exact variant, so we confirm them against your model code rather than publishing a number that may not apply to your pump.
| Set contents | Cylinder block, pistons with shoes, retainer plate, ball guide, valve plate and spring set |
|---|---|
| Matching | Parts lapped and matched as one running set |
| Spline | To the original pattern, checked over pins |
| Marking | Neutral or your own part number on request |
| Packing | Oiled and vacuum sealed, boxed per set |
| Performance data | Confirmed against the full model code on your unit before quotation |
Materials
| Cylinder blocks | Case hardening steel with a sintered bronze running face, bonded and machined after sintering |
|---|---|
| Pistons and shoes | Case hardening steel with a bronze shoe face, swaged and hydrostatically balanced |
| Valve plates | Bearing steel or bronze faced steel depending on the frame, lapped to a mirror finish |
| Drive shafts | Alloy steel, carburised and hardened on the spline and bearing seats, ground on centres |
| Vanes and rotors | High speed tool steel and case hardening steel, hardened and ground on all working faces |
| Cam rings | Bearing quality alloy steel, through hardened then profile ground |
| Seals | Nitrile as standard, fluorocarbon or polyurethane on request for hot or fire resistant fluid duty |
Manufacturing Process
- Turning and millingBlanks are turned and milled from certified bar and forging stock on CNC machines.
- Heat treatmentCarburising, quenching, tempering or nitriding to the route the original part uses.
- GrindingBores, spline seats and running faces are ground after heat treatment so distortion is removed.
- Lapping and superfinishingValve plates, shoe faces and block faces are lapped so the pair seals under pressure.
- InspectionDimensions, hardness and surface finish are recorded against the drawing on a sampling plan.
- Assembly and testComplete pumps are built, run in and tested for efficiency, leakage and noise before packing.
Quality Control
- Incoming material certificates are checked against the grade called for on the drawing.
- Hardness is measured after heat treatment on every batch and recorded on the batch card.
- Critical bores and running faces are gauged against the drawing tolerance, not against a sample part.
- Mating parts are matched as a set so the block, shoes and valve plate run in together.
- Rebuilt pumps are bench tested for volumetric efficiency, external leakage and sound level.
- Parts are cleaned, oiled and vacuum sealed so they arrive without surface rust.
Certifications and Documentation
Supplied on request with an order. We do not claim approvals we cannot evidence.
| Material certificate | Mill certificate for the steel grade used in the batch |
|---|---|
| Hardness report | Surface and core hardness readings after heat treatment |
| Dimensional report | Measured values for the critical features named on the drawing |
| Test bench report | Flow, efficiency, leakage and sound readings for a rebuilt pump |
| Packing list and photographs | Carton contents and photographs of the packed goods before shipment |
Customization Options
- Shaft and splineKeyed, straight or splined shaft ends built to your sample or drawing.
- Port and mountingFlange, thread and mounting pattern matched to the pump already on the machine.
- Seal materialNitrile, fluorocarbon or polyurethane for hot oil, fire resistant fluid or low temperature duty.
- Rotation and displacementLeft or right hand rotation and the displacement code your circuit was set up for.
- Marking and packingNeutral packing, your own carton artwork and your own part number laser marked on the part.
Comparison With Other Products
| Point | A6VM | A2FM | A11VO |
|---|---|---|---|
| Function | Variable displacement motor | Fixed displacement motor | Variable displacement pump |
| Speed range | Wide, control adjusts angle | Fixed | Not applicable |
| Sizes we build | 28 to 1000 | 10 to 1000 | 35 to 500 |
| Typical duty | Travel and drum drive | Winch and drum drive | Heavy work function |
Use Guide
- Record the full model code and the serial plate before stripping the unit.
- Measure the housing bore and bearing seats. A worn housing will kill a new rotary group.
- Fit the set complete rather than mixing new and used running faces.
- Renew the seal kit and the shaft bearing at the same time.
- Flush the circuit, prime the case with clean oil and run in at low pressure.
Product Photographs
Related Products
A4VSO Series Rotary Groups
A4VSO and A4V rotary groups and spare parts in sizes 28 to 500, supplied as matched sets with cylinder block pistons valve plate and swash plate.
View Series and Sizes
A4VG Series Rotary Groups
A4VG closed circuit rotary groups and spare parts in sizes 28 to 500 for self propelled machine drive circuits, supplied as matched sets.
View Series and Sizes
A7VO and A8VO Series Rotary Groups
A7V A7VO and A8VO bent axis rotary groups and spare parts in sizes 28 to 1000 for excavator and heavy mobile main pumps.
View Series and Sizes
Related Industry Applications
Construction Machinery
See the ApplicationMining and Quarry
See the ApplicationMarine and Offshore
See the Application
Related Project Cases
Excavator Travel Motor Rebuild Programme in Turkey
Read the CaseStocking Cartridge Kit Programme for a German Distributor
Read the CaseMarine Winch Pump Refit for a Canadian Repair Yard
Read the Case
Related Articles
Frequently Asked Questions
Why will the machine not reach full travel speed?
Either the control is not swinging the motor to minimum displacement, or the rotary group is worn. Check control pressure before stripping.
Do you supply the control parts?
Common control parts are available. Send the full model code including the control letters.
Are A6V and A6VM parts the same?
They belong to the same family but differ by variant. The model code tells us which parts apply.
Do you stock piston rings for this family?
Yes, by size group, and they are often ordered on their own.
Can you supply matched sets for two motors on one machine?
Yes. Order both together and we will match the sets so the two sides behave the same.
Send Us the Model Code and We Will Quote
Tell us the model code stamped on the pump, the quantity and your delivery port. A quotation with lead time usually comes back within one working day.