ITM11-1000 STF Radial Piston Motor 981cc 16MPa

Product Overview

The ITM11-1000 is a large-displacement radial piston hydraulic motor from the STF (Ningbo STF Hydraulic Transmission Co., Ltd.) ITM series, ITM11 frame size. The ITM series motors are designed and manufactured based on the structure and performance characteristics of Italian-type roller force-transmission radial piston hydraulic motors, produced with high-standard technical requirements, high-performance production equipment, and advanced manufacturing processes to achieve comprehensive performance levels comparable to international equivalents.

The ITM11-1000 offers a theoretical displacement of 981 ml/r, rated pressure of 16 MPa, peak pressure of 20 MPa, rated torque of 2296 N·m, unit torque of 145 N·m/MPa, maximum power of 51 kW, maximum speed of 320 rpm, and weight of approximately 51 kg. This model is primarily designed for injection molding machine screw drives, melt motors, and feed motors, compatible with leading injection molding machine brands including Haitian.

ITM11 series motors employ a crankshaft & connecting rod structure with low-excitation-frequency five-cylinder/five-piston or seven-cylinder/seven-piston mechanisms, delivering low-noise operation. They feature high starting torque with stable operation at extremely low speeds, a flat compensable oil distribution structure for good reliability and low leakage, reversible rotation, and output shafts capable of withstanding certain radial and axial external forces.

The motors offer complete interchangeability: mounting dimensions and interfaces are identical to original STF products. The ITM series also serves as a proven replacement for German Rexroth MCR series, French Poclain MS series, Staffa HMB/HMC series, Denison/Calzoni MR/MRE series, and other international mainstream brand hydraulic motors. Every unit undergoes 100% simulated duty-cycle testing before shipment.

Technical Specifications 

ITM11-1000 (Primary Model)

• Model: ITM11-1000

• Brand Series: STF ITM Series / ITM11

• Motor Type: Radial piston, crankshaft & connecting rod structure, low-speed high-torque

• Theoretical Displacement: 981 ml/r

• Rated Pressure: 16 MPa

• Peak Pressure: 20 MPa

• Rated Torque: 2296 N·m

• Unit Torque: 145 N·m/MPa

• Maximum Power: 51 kW

• Maximum Speed: 320 rpm

• Minimum Speed: 3 rpm

• Piston Configuration: Five-cylinder/five-piston or seven-cylinder/seven-piston

• Distribution: Flat compensable oil distribution structure

• Rotation: Bi-directional reversible

• Output Shaft Loading: Certain radial and axial external forces permitted

• Mounting: Flange mount

• Weight: Approximately 51 kg

• Applications: Injection molding machine screw drives, melt motors, feed motors

ITM11 Series Other Displacement Sizes (Series Reference)

• ITM11-700: Theoretical displacement 682 ml/r, rated pressure 16 MPa, peak pressure 22 MPa, rated torque 1596 N·m, unit torque 101 N·m/MPa, max power 40 kW, max speed 400 rpm, weight 95 kg

• ITM11-800: Theoretical displacement 782 ml/r, rated pressure 16 MPa, peak pressure 22 MPa, rated torque 1830 N·m, unit torque 116 N·m/MPa, max power 46 kW, max speed 400 rpm, weight 95 kg

• ITM11-900: Theoretical displacement 894 ml/r, rated pressure 16 MPa, peak pressure 22 MPa, rated torque 2092 N·m, unit torque 132 N·m/MPa, max power 52 kW, max speed 400 rpm, weight 95 kg

• ITM11-1000: Theoretical displacement 981 ml/r, rated pressure 16 MPa, peak pressure 20 MPa, rated torque 2296 N·m, unit torque 145 N·m/MPa, max power 51 kW, max speed 320 rpm, weight 51 kg

• ITM11-1100: Theoretical displacement 1104 ml/r, rated pressure 16 MPa, peak pressure 20 MPa, rated torque 2584 N·m, unit torque 163 N·m/MPa, max power 57 kW, max speed 320 rpm, weight 57 kg

• ITM11-1200: Theoretical displacement 1234 ml/r, rated pressure 14 MPa, peak pressure 18 MPa, rated torque 2527 N·m, unit torque 182 N·m/MPa, max power 49 kW, max speed 320 rpm, weight 49 kg

• ITM11-1300: Theoretical displacement 1301 ml/r, rated pressure 14 MPa, peak pressure 18 MPa, rated torque 2664 N·m, unit torque 192 N·m/MPa, max power 47 kW, max speed 250 rpm, weight 47 kg

Note: ITM11 series parameters are compiled from the STF ITM series technical data table.

ITM03 Series (Series Reference)

• Displacement Range: 181–350 ml/r

• Torque Range: 175–450 N·m

• Rated Pressure: 16 MPa

• Peak Pressure: 22 MPa

• Mounting: Flange mount

• Variants: ITM03-B, ITM03-1, ITM03-SL/SL2

• Typical Applications: Medium-load industrial transmission systems

Key Technical Advantages

① Crankshaft & Connecting Rod Structure with Low Excitation Frequency — Low Noise, Smooth Operation

The ITM11-1000 employs a crankshaft and connecting rod structure combined with a low-excitation-frequency five-cylinder/five-piston or seven-cylinder/seven-piston design. Compared to conventional gear or vane motors, this structure significantly reduces vibration and noise during operation, making it particularly suitable for injection molding machines and other applications with strict noise requirements. The sequential firing of multiple pistons ensures continuous and smooth torque output, effectively suppressing stick-slip at low speeds.

② Flat Compensable Oil Distribution Structure — High Reliability, Low Leakage

The ITM11 series features a flat compensable oil distribution mechanism. The interface between the valve plate and cylinder block employs a compensable sealing design that automatically compensates for wear clearance during long-term operation, maintaining stable sealing performance. Compared to conventional distribution structures, this design effectively reduces internal leakage, improves volumetric efficiency, and simplifies maintenance procedures.

③ High Starting Torque and Excellent Low-Speed Stability — Heavy-Load Breakaway Without Compromise

The ITM11-1000 features high starting torque characteristics, with starting torque approaching theoretical value. In injection molding machine screw drives and other applications requiring breakaway of high-inertia loads, the motor delivers ample instantaneous torque output. Additionally, the motor maintains smooth operation at speeds as low as 3 rpm with pulseless torque output, meeting the precise speed control requirements of injection molding melt and feed processes.

④ Bi-Directional Rotation and High-Load Output Shaft — Flexible Installation Adaptability

The ITM11-1000 supports bi-directional rotation, with hydraulic ports featuring clear flow direction markings for easy system configuration and installation. The output shaft accommodates certain radial and axial external forces, enabling direct driving of belt pulleys, sprockets, or gears without additional support bearings. Standardized mounting flange and splined output shaft design enables direct replacement of equivalent STF original motors.

⑤ Broad Interchange Compatibility — Direct Replacement Across Multiple Brands

The ITM11-1000’s standardized mounting interfaces and hydraulic parameters allow direct replacement of German Rexroth MCR series, French Poclain MS series, Staffa HMB/HMC series, Denison/Calzoni MR/MRE series, Kawasaki SX series, and other international mainstream brand hydraulic motors. For users operating imported injection molding equipment, the ITM11 series offers a cost-effective domestic replacement solution without modifying piping or mounting brackets.

Application Areas

• Injection Molding Machines: Screw drives, melt motors, feed motors, storage motors (compatible with Haitian and mainstream injection molding machine brands)

• Plastics Machinery: Extruder screw drives, blow molding machine drives

• Marine Deck Machinery: Winches, windlasses, hatch cover drives

• Mining Machinery: Drill rotary drives, roadheader drives

• Construction Machinery: Rotary drilling rigs, crawler crane slew drives

• Heavy Metallurgical Machinery: Plate rolling machines, rolling mill auxiliary drives, continuous casting equipment

• Oil & Coal Mining Machinery: Drill drives, coal mining machinery transmission

• Lifting & Transportation Equipment: Drum drives, winch hoisting

• Machine Tools & Light Industry Equipment: Rotary tables, various hydraulic transmission systems

Expert Maintenance Tips

Pre-Installation Inspection: Verify flatness and cleanliness of the mounting flange mating surface; check thread condition of mounting bolt holes. The splined output shaft-to-coupling or drive-wheel fit must conform to standards, avoiding interference fits that could damage the spline. Use bolts of strength class 8.8 or higher, tightened in diagonal sequence to specified torque.

First Commissioning: The motor casing must be filled with clean hydraulic oil before initial start-up. Fill through the highest casing port until oil overflows from the level port. Dry starting causes metal-to-metal contact between piston-to-bore surfaces and the flat valve plate without lubrication, resulting in irreversible damage. For injection molding applications, a no-load run-in is recommended before initial operation of the melt motor.

Fluid Cleanliness: Maintain system oil cleanliness at NAS 8 (ISO 4406 18/16/13) or better. The radial piston motor’s flat distribution surfaces and piston pairs are sensitive to particulate contamination; excessive contamination accelerates valve plate wear and causes volumetric efficiency degradation. Inspect return filter elements regularly and replace per the machine manufacturer’s recommended interval.

Scheduled Inspection: Check casing drain flow and output shaft spline wear every 500 operating hours. Under normal conditions, drain flow should remain stable; a sustained increase indicates accelerated wear of piston pairs or flat valve plate, and preventive maintenance should be scheduled. Also inspect the output shaft spline interface for abnormal clearance increase or wear marks.

Long-Term Storage Protection: If the motor will be idle for more than 3 months, fill the casing with rust-preventive hydraulic oil and manually rotate the shaft several turns monthly to prevent corrosion or adhesion on piston-bore interfaces and flat valve plate surfaces. Perform a no-load run-in before returning to service.