Volvo 55 Travel Motors Assembly PHV-4B-70D
Original Teijin Seiki Nabtesco Japan GM09
1. Product Overview
TheGM07is a core travel drive component designed by Doosan Infracore (Korea) for mid-sized excavators (e.g., DX80/DX130/DX150 series). It features anaxial piston motor + planetary gearboxintegrated structure, delivering high torque output, strong impact resistance, and adaptability to complex working conditions. Compliant with ISO 13032 hydraulic motor standards, it is widely used in mining, construction, and earthmoving applications.
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2. Core Functions
• Bidirectional Drive Control: Supports forward/reverse motion for straight travel, crab steering, or pivot turns.
• Dynamic Torque Adjustment: Built-in pressure compensation valve automatically adjusts output torque (range: 500–3,500 N·m) based on load.
• Hydraulic Brake Integration: Spring-applied brake (braking torque ≥3,200 N·m) with hydraulic release pressure of 160–180 bar.
• Sealing Protection System: Dual-lip seals + dust wiper prevent mud/water/dust ingress, extending service life.
• Low-Temperature Start: Operates at -25°C, suitable for cold-region operations.
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3. Technical Specifications
【表格】
Parameter Specification
Model GM07 (Doosan Part No.: 420-00072)
Applicable Models Doosan DX80/DX130/DX150 series
Displacement 70 mL/r (per revolution)
Rated Pressure 280 bar (continuous)
Peak Pressure 320 bar (instantaneous max)
Output Speed 0–15 rpm (stepless adjustment)
Reduction Ratio 1:6.2 (planetary gearbox)
Port Type SAE 6B (port size: M24×1.5)
Brake Type Hydraulic release + spring brake
Weight Approx. 92 kg
Protection Grade IP67 (dust/waterproof)
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4. Structural Components
(1) Hydraulic Motor Section
• Cylinder Block & Pistons: 7 axial pistons made of 42CrMo4 alloy steel with hard chrome plating (≥850 HV).
• Port Plate: Copper-based alloy (ZQSn10-2) with dual-kidney oil passages for optimized high/low-pressure switching.
• Bearing System: Double-row tapered roller bearings (Model 30312) for radial/axial load (rated static load: 120 kN).
• Swashplate Mechanism: Spherical porting design with 12° tilt angle for displacement adjustment.
(2) Gearbox Section
• Planetary Gear Set: 3-stage planetary reduction with sun/planet gears made of 20CrMnTi (carburized/quenched to 58–62 HRC).
• Output Shaft: Splined shaft (module 3.5, teeth 22) mates with track drive sprocket, transmitting torque ≥3,200 N·m.
• Housing: Ductile iron (QT500-7), wall thickness ≥25 mm, impact strength ≥120 J/cm².
(3) Brake & Sealing
• Spring Brake: Disc spring group provides 3,200 N·m braking torque with ≤0.3-second response time.
• Shaft Seal: Fluororubber (FKM) dual-lip seal, temperature range -40°C to +180°C, chemical-resistant.
• Dust Wiper: Polyurethane (PU) scraper (90 Shore A) blocks particles ≥0.5 mm in diameter.
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5. Common Faults & Solutions
【表格】
Symptom Possible Causes Solutions
Weak Travel/Slow Speed Hydraulic oil contamination, brake not released, internal leakage Replace hydraulic oil (ISO VG46), check brake pressure, replace seals
Travel Vibration Piston wear, gear misalignment Repair piston pair (coating restoration), replace planetary gear set
Abnormal Noise Bearing failure, gear tooth fracture Replace tapered roller bearings, check gear backlash (standard 0.1–0.3 mm)
Oil Leakage Aged shaft seal, housing crack Replace FKM seal, weld housing (use E7018 electrode)
Brake Failure Broken brake spring, hydraulic circuit fault Replace disc spring group, inspect brake valve block
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6. Maintenance Recommendations
• Daily Checks:
• Every 500 hours: Verify oil level, seal condition, and brake pressure (normal range 160–180 bar).
• Clean radiator fins to prevent hydraulic oil overheating (working temperature ≤85°C).
• Oil Requirements:
• Use Doosan-specified hydraulic oil (Doosan Hydraulic Oil Premium 46), cleanliness ≤NAS 1638 Class 8.
• Do not mix oils of different brands/viscosities.
• Replacement Intervals:
• Seals: Every 2,000 hours (or when leakage occurs).
• Bearings: Every 4,000 hours (or when abnormal noise occurs).
• Gear oil: Every 1,000 hours (gearbox section, recommended EP 220).
• Storage Conditions:
• For long-term storage (>30 days), fill with hydraulic oil and store vertically at -25°C to +50°C.
