Compatibility Statement: 708-1T-00620 Hydraulic Pump Assembly for HM400 Articulated Dump Trucks
1. Component Overview
• Model: 708-1T-00620
• Type: Dual Variable Displacement Piston Pump (Integrated Main + Auxiliary Pump Design)
• Function:
Provides hydraulic power to the steering system, lift mechanism, and braking system of HM400 trucks, ensuring precise control and safe operation under complex terrain conditions.
2. Applicable Model & Core Specifications
• Compatible Models: Komatsu HM400-3 / HM400-5 Articulated Dump Trucks (Tier 4 Final Emission Compliance)
• Engine Matching:
• Model: SA6D140E-7 (Tier 4 Final, 397 kW / 533 HP)
• Speed Range: 1,600–2,000 rpm (Rated Input Speed for Pump)
• Hydraulic Interface:
• Main Pump Outlet: SAE 12-Tooth Port (350 bar Pressure Rating)
• Auxiliary Pump Outlet: SAE 10-Tooth Port (210 bar Pressure Rating)
• Return Port: M24×1.5 Thread (25 mm Bore Size)
3. Technical Parameter Comparison (708-1T-00620 vs. HM400 System Requirements)
【表格】
Parameter 708-1T-00620 Specifications HM400 System Requirements Compatibility
Main Pump Flow 280 L/min (at 2,000 rpm) Steering + Lift Demand: 260–300 L/min ✅ Meets
Auxiliary Pump Flow 80 L/min (at 2,000 rpm) Brake System Demand: 70–90 L/min ✅ Meets
Total Weight 125 kg Max Allowable Pump Weight: 130 kg ✅ Compliant
Mounting Dimensions Length 450 mm × Width 300 mm × Height 280 mm Factory Pump Space: 500×350×300 mm ✅ Fits
Noise Level ≤88 dB(A) (at 1 m) System Noise Limit: 92 dB(A) ✅ Exceeds Standard
4. Installation & Commissioning Guidelines
（1）Hydraulic Oil Requirements
• Viscosity Grade: ISO VG 68 (Applicable for -15°C to +60°C)
• Cleanliness Standard: ISO 4406 18/16/13 (or NAS 1638 Class 6)
• Additive Requirements: Anti-wear, anti-foam, and anti-corrosion additives
（2）Installation Steps
1. Remove Original Pump Assembly(Part No. 708-1T-00580):
• Drain hydraulic tank to 50 mm below the minimum level to prevent oil spillage.
• Label main and auxiliary pump hose connections (avoid misrouting).
2. Install New Pump Assembly:
• Use laser alignment tools to ensure pump shaft coaxiality with the engine crankshaft ≤0.08 mm.
• Tighten mounting bolts crosswise in three steps to 220 N·m (Step 1: 80 N·m, Step 2: 150 N·m, Final: 220 N·m).
3. Hose Connections:
• Main pump high-pressure hoses require double-walled lines (19 mm ID, 400 bar rating).
• Auxiliary pump hoses must include a flow control valve (set to 200 bar).
（3）Commissioning Tips
• Initial Operation:
• Run at idle speed for 30 minutes after startup; check pump temperatures (main pump ≤90°C, auxiliary pump ≤85°C).
• Monitor system pressures: main pump outlet 340–350 bar, auxiliary pump 200–210 bar.
• Functional Testing:
• Steering Test: Hydraulic response time ≤1.5 seconds at full steering angle.
• Lift Mechanism Test: Empty lift to maximum height in ≤8 seconds.
• Brake System Test: Hydraulic lock time ≤0.3 seconds during emergency braking.
