Slewing Swing Motor Assembly for Caterpillar 305.5E2CR Mini Excavator
NACHI PCR-4B-20A-FP
Product Overview
NACHI PCR‑4B‑20A‑FP is a compact radial piston Hydraulic piston motor, specially designed as the slewing drive unit for Caterpillar 305.5E2CR mini excavator. This high‑performance hydraulic motor is the core executive component of the excavator slewing hydraulic system, converting hydraulic pressure energy into stable low‑speed high‑torque rotary power to realize 360° smooth rotation of the upper platform. Integrated with built‑in relief valve, anti‑shock valve and parking brake, the motor features compact structure, strong overload resistance and excellent sealing performance. It strictly matches the original hydraulic circuit parameters of CAT 305.5E2CR, and is widely used for OEM replacement, field overhaul and aftermarket spare‑parts matching of small construction machinery. The reliable operation of this Hydraulic piston motor directly guarantees the stability and safety of the whole slewing hydraulic system.
Technical Specifications
- Model: NACHI PCR‑4B‑20A‑FP
- Applicable Equipment: Caterpillar 305.5E2CR Mini Excavator
- Motor Type: Radial piston Hydraulic piston motor, dedicated slewing hydraulic motor
- Max continuous working pressure: 245 bar; Peak pressure: 280 bar
- Displacement: Optimized matching for 5‑ton class mini excavator
- Built‑in functions: Pressure relief valve, anti‑cavitation valve, mechanical parking brake
- Installation: Flange mounting, pinion output structure
- Working medium: Anti‑wear hydraulic oil for mobile construction hydraulic system
- Operating temperature: -20℃ ~ +85℃
- Feature: Low backlash, stable low‑speed operation, strong shock resistance, perfect dimensional matching with original equipment, suitable for frequent forward and reverse rotation of excavator slewing mechanism
Working Principle
High‑pressure hydraulic oil from the main control valve of the hydraulic system enters the oil port of this hydraulic motor, pushing the radial piston group to actuate and driving the output shaft to rotate with large torque. The built‑in relief valve limits the maximum system pressure to avoid overload damage to the excavator; the parking brake automatically locks the motor when the machine stops working to prevent platform drifting. When internal pistons, cam rings or sealing parts of the Hydraulic piston motor are worn, faults such as weak slewing power, slow rotation speed, oil leakage and abnormal noise will occur. Replacing a qualified NACHI PCR‑4B‑20A‑FP motor can fully restore the slewing performance and keep the hydraulic system running stably.
Core Advantages
1. Authentic NACHI hydraulic design, integrated valve group simplifies pipeline layout of the hydraulic system, reduces assembly difficulty of the mini excavator.
2. Radial piston structure provides large starting torque, stable operation at low speed, adapting to frequent slewing working conditions of small construction Machine.
3. Built‑in anti‑shock and parking brake functions, effectively absorb hydraulic impact, improve operation safety and protect the hydraulic motor from overload damage.
4. High‑precision friction pairs and heavy‑duty seals, strong contamination resistance, adapting to dusty construction site environments, extending service life of the Hydraulic piston motor.
5. Strictly conforms to original mounting dimensions, direct replacement without secondary processing, convenient for on‑site maintenance and overhaul.
Application Range
NACHI PCR‑4B‑20A‑FP Hydraulic piston motor is a key slewing power component for the mobile hydraulic system of compact construction machinery. It is specially applied to Caterpillar 305.5E2CR mini excavators, and can also be used for matching and renovation of similar small engineering equipment. Widely supplied for machinery repair workshops, maintenance service stations and global aftermarket spare‑parts trading business.
