Hydraulic machine drives

Dongyu Hydraulics
Start with the moving part.

A track drive turns its housing; a power-head drive delivers motion through its output shaft. Dongyu's DFT17T3 and DYD309 show why the hydraulic motor, gear stages, brake and machine connection need to be selected as one assembly.

Compare the two layouts Prepare the hydraulic circuit →

Choose the mechanical architecture

Wheel or track travel is a different assembly from a power head.

Start by identifying what moves, what stays fixed and where the machine loads enter the drive. These two official examples have different ratio ranges, motor selections and rotation relationships.

DFT17T3 · rotating-housing travel drive

The DFT family connects the rotating housing to a wheel or track mechanism. Dongyu describes an integrated multi-disc parking brake and support for external radial and axial loads. The chassis and rotating wheel/track connections must be identified separately.

DFT17T3 directory specifications →

DYD309 · output-shaft power-head drive

The DYD description combines planetary reduction with a functional distribution-valve arrangement. Its output shaft carries the driven connection. Dongyu offers brake and valve options; a suitable output gear can form a slewing arrangement after selection.

Official DYD309 configuration ↗

Read each column as its own published configuration.

The table preserves the two original web specifications. Their torque field is Tmax — maximum output torque, not a continuous rated-torque promise. Ask for the operating envelope of the selected motor, ratio and duty.

Published field	DFT17T3 travel drive	DYD309 power-head drive
Maximum output torque, Tmax	17,000 Nm	16,000 Nm
Listed reduction ratios, i	77.9 / 88.2 / 102.6	16 / 25.4 / 28 / 32.6
Listed hydraulic motors	A2FE28 / A2FE32 / A2FE45 / A2FE56 / A6VE28 / A6VE55	A6VM107
Published input speed	2,000 rpm	2,500 rpm
Static brake torque, TBr max	220–350 Nm	0 in the shown configuration
Brake operating pressure	1.8–5 MPa	0 in the shown configuration
Input / output rotation	Opposite directions	Same direction
Permissible output speed	Not specified in either web table; Dongyu requires selection against actual operating conditions.

DFT17T3 page dated 6 April 2022; DYD309 page dated 8 April 2022. The web tables do not establish every motor/ratio combination's continuous torque or thermal capacity. Obtain the selected configuration's limits and current drawing before ordering.

Define the torque cycle

Provide working torque, start-up load, peak duration, reversals and run/rest periods. Ask which limit is continuous, intermittent or a short-duration maximum and how hydraulic pressure, speed and oil temperature affect it.

Keep motor and reducer selection together

Specify the exact motor displacement/control, ratio and circuit. Dividing the listed input speed by the ratio gives a kinematic relationship; it does not establish the permissible output speed, load or thermal duty.

A brake is a separate selection

Parking, stopping and direction need explicit agreement.

The DFT example lists a static brake torque range. DYD309 prints zero in its brake columns while the surrounding family description offers optional brakes and valves.

DFT17T3: verify the parking-brake installation

Agree the brake's location in the selected assembly, release-pressure circuit, return/back pressure and holding requirement. The catalog's static value is not a dynamic stopping-energy rating and should not be treated as the wheel's guaranteed holding torque without confirming its reference location.

DYD309: specify any optional brake

The zero entries describe the example shown. If your machine needs a holding or stopping function, name that requirement and obtain the fitted brake's data rather than borrowing the DFT17T3 values.

Check rotation from a defined viewing direction

DFT17T3 states opposite input/output rotation; DYD309 states the same direction. Put the viewing end, port connections, commanded direction and actual machine motion into the drawing and commissioning check.

For a travel-drive replacement, compare both mounting sides.

The official DFT17T3 drawing shows the chassis and wheel/track connections as different interfaces. A matching torque headline cannot establish a bolt-in replacement.

Official DFT17T3 outline. Open the complete drawing to inspect both mounting faces; obtain the current selected assembly revision for manufacture.

Fixed side

Mark chassis locating surfaces, fasteners, axial clearance and motor/port access. Confirm which drawing dimensions include the hydraulic motor and which apply only to the reduction unit.

Rotating side

Show wheel hub or track sprocket geometry, fastening pattern, wheel radius and load offset. Give the actual radial/axial forces and overturning moment with their directions and load cases.

Bearing and seal conditions

Request a load/life check for the installed geometry and duty. A bearing capacity printed on an outline is not, on its own, an allowable external force for every machine installation. Agree sealing, lubrication, drainage and service access for the environment.

Send a hydraulic schematic with the mechanical brief.

Dongyu's portfolio includes DMS/DGM hydraulic motors, DFT travel drives, DYD power-head drives, DYNJ winches and DYH planetary transmission. Identify the complete supply boundary for your machine.

01 · Hydraulic supply

Pressure, flow and oil conditions

Provide supply pressure/flow over the cycle, return and case-drain conditions, oil specification, filtration, temperature and cooling. Identify starts under load and low-speed operation; request the selected motor's permissible conditions.

02 · Motion and safety

Control and load handling

Describe downhill/overrunning loads, reversals, emergency stops and holding requirements. Agree the valve arrangement, brake release/control sequence and machine safety responsibilities with the drive supplier.

03 · Purchase scope

What arrives as one assembly?

State whether the supply includes reducer, motor, brake, valve block, ports, seals, lubricant and output gear. Obtain an assembly drawing, component list, settings and inspection requirements for the ordered configuration.

A hydraulic-drive manufacturer in Ningbo's Zhenhai district.

Dongyu's official company page states that Ningbo Dongyu Hydraulics was established in September 2016. It describes development and manufacture of hydraulic motors, winches, rotary drives, planetary reducers and wheel-travel devices for construction machinery, mining, petroleum, metallurgy, marine, agricultural and environmental equipment.

The legal Chinese name 宁波东裕液压有限公司 also appears as entry 89 in Ningbo's 2024 third-batch technology-based small and medium enterprise list. This historical record corroborates the named entity; it is not a certification of the two drive configurations or a substitute for their performance tests.

For procurement, align the purchase-order entity, assembly model, drawing revision and supplied components. Define inspection around the intended pressure/speed/load cycle, rotation, brake operation, leakage, temperature and mounting interfaces rather than an isolated maximum torque.

Build a complete hydraulic-drive enquiry.

Send the machine connection, hydraulic circuit and duty together so Dongyu can select the assembly.

Prepare sourcing request

Save Dongyu Hydraulics to include it in your request.

Machine function: wheel/track travel, power head, slew or winch; quantity and destination.
Fixed/rotating connections, output geometry, available envelope and drawing.
Required speed and torque/time cycle; external loads and offsets.
Motor selection, hydraulic supply/return/drain conditions, oil and temperature.
Rotation/viewing end, valves, holding/stopping needs and fitted brake data.
Assembly supply scope, selected limits, drawing revision and agreed inspection record.

Sources & review

Reviewed 8 October 2026. Product values and images are supplier-published; integration checks are editorial guidance. Historical company evidence is dated separately.

Dongyu · DFT17T3 travel reducer ↗Original parameter table, rotating-housing description, parking brake, rotation/speed footnotes, product photograph and complete drawing.
Dongyu · DYD309 power-head reducer ↗Separate parameter table, motor, optional brake/valve scope, rotation/speed footnotes and official product image.
Dongyu · official company introduction ↗Chinese legal name, stated September 2016 establishment, location, portfolio and applications.
Ningbo · 2024 third-batch technology-based SME list ↗Page 4, entry 89: 宁波东裕液压有限公司, identifier 2024330211A8005393. Historical entity corroboration only.