Detailed Product Description for Sany Original Tandem Gear Pump Assembly 1162112923T

I. Basic Material Information

II. Core Function Definition

Pilot Control Oil Supply (First Pump Section)

System Oil Replenishment + Lubrication & Cooling (Second Pump Section)

Pressure Stabilization & Buffering

Compact Integrated Layout

III. Overall Structure & Material Grading of Key Components

1. Overall Structural Layout (From Input Shaft End to Dual Oil Outlet End)

2. Material and Heat Treatment Technology for Core Components

IV. Precise Technical Parameters

V. Core Product Advantages

1. Precise Interchangeability with Original Factory Code

   
   

   With Sany material code 150107010220A and part number 1162112923T, its flange dimension, input spline specification, oil port orientation and mounting hole position are 100% compatible with the rear mounting position of K7V280 main pump on SY1250H/SY1350H. No shaft modification, pipeline alteration or machining required for direct disassembly and replacement with zero assembly tolerance, matching original factory calibrated pilot pressure parameters.
2. Long Service Life Adopting Floating Side Plate Clearance Compensation Design

   
   

   The automatic compensation structure of end-face floating side plates offsets gear end-face wear to achieve slow volumetric efficiency attenuation in long-term use, eliminating common troubles such as low pilot pressure and sluggish movements. Adopting precision gear grinding technology, gears mesh smoothly with small pressure pulsation and low operating noise, ideal for non-stop long-hour mining operation of ultra-large excavators.
3. Independent Oil Supply for Dual Circuits with Clear System Division

   
   

   One circuit specially for pilot control and the other for oil replenishment and lubrication, with independently stabilized pressure without mutual interference. It not only ensures stable operation feel, but also continuously lubricates and cools primary and secondary hydraulic components, greatly reducing premature wear failure rate of main pump and motors and extending overall service life of hydraulic system.
4. Integrated Monolithic Structure Reducing Leakage Failures

   
   

   The integrated tandem structure eliminates two separate gear pumps and intermediate couplings, cutting the quantity of joints, hoses and brackets as well as leakage points. Compact overall structure fits the compact hydraulic compartment layout of SY1250H/SY1350H.
5. Convenient Maintenance & Controllable Repair Cost

   
   

   Wearing parts including oil seals, side plates, gear assemblies and shaft seals can be disassembled and replaced separately without replacing the whole pump assembly to reduce after-sales overhaul cost. Both end caps are easy to disassemble for internal wear inspection and air venting troubleshooting.

VI. Key Operation Points for Installation & Replacement

1. System Pressure Relief Preparation: Shut down the engine, repeatedly actuate all control levers to release residual pressure inside hydraulic system, disconnect negative terminal of storage battery and implement safety protection for high-pressure hydraulic work.
2. Pipeline Disassembly: Remove pilot outlet hose, oil replenishment circuit outlet hose and common oil inlet suction hose in sequence, mark pipelines to prevent reverse connection, and clean dirt and impurities on pipe joints.
3. Old Pump Removal: Loosen fixing bolts of gear pump and pull out the old tandem gear pump assembly steadily. Clean oil stains, rust and wear debris on mounting end face and input spline at rear of main pump, and check the drive spline of main pump for collision damage.
4. Positioning Assembly of New Pump: Apply a small amount of hydraulic oil for lubrication on shaft-end oil seal of new pump, align splines and push smoothly to fit mounting surface, tighten fixing bolts evenly in diagonal multiple passes to avoid assembly damage to oil seal caused by eccentric load extrusion.
5. Pipeline Reassembly: Restore all hydraulic hoses according to marks, replace all O-rings with brand-new ones, tighten pipe joints evenly to eliminate hidden leakage risks.
6. Oil Filling, Air Bleeding & Running-In: Fill qualified hydraulic oil, start engine at idle speed, operate all levers repeatedly to exhaust air inside pump and pipelines, perform 30-minute no-load running-in, and check pump body, shaft end and oil ports for oil seepage, abnormal noise and vibration.
7. Machine Acceptance & Calibration: Use pressure gauge to detect whether the output pilot pressure and oil replenishment pressure of two circuits fall within original factory standard range. The installation is qualified if all machine movements run at even speed with smooth response without sluggishness and insufficient power.

VII. Common Faults, Causes & Operational Hazards

Slow overall machine movements, heavy operation, unstable and low pilot pressure

Abnormal noise, periodic sound and excessive vibration of gear pump

Oil seepage and leakage at shaft end, end caps and oil ports

Insufficient oil replenishment pressure, high temperature, abnormal noise and aggravated wear of main pump

Pump seizure and complete failure of all machine movements

VIII. One-Stop Supporting Supply List (Complete Spare Parts for Pilot System)

• Same-model 1162112923T tandem gear pump assembly and original replacement units
• Complete oil seal repair kits, end cap sealing gaskets and shaft seal assemblies for gear pump
• Internal repair kits including drive/driven gears, floating side plates and drive shaft
• Spare parts for pilot overflow pressure regulating valve, check valve and pressure sensor
• Pilot filter element, inlet suction hose, high-pressure pilot hose and pipe joint assembly
• Pilot handles of main control valve, electronic solenoid valves and complete pilot wiring harness assembly for SY1250H/SY1350H
• Rear sealing kit for K7V280 main pump and matching sealing accessories for main pump through shaft