SHIMADZU SDY Series High-Pressure Gear Pump
Product Overview
The SDY series is a high-pressure gear pump manufactured by SHIMADZU Corporation through its authorized facility, Tianjin Shimadzu Hydraulic Co., Ltd. (TSH). This series represents SHIMADZU‘s premier hydraulic power solution specifically engineered for forklifts and construction machinery, forming a core product line alongside the SGP1 and SGP2 series.
The SDY series features a cast iron body combined with aluminum alloy components, delivering high strength with optimized weight. Renowned for exceptional durability, high efficiency, and low noise, the SDY series has passed 1 million impact fatigue tests at 24.5 MPa operating pressure. Fully interchangeable with equivalent models from other major brands, the SDY series is the ideal hydraulic power choice for forklifts, wheel loaders, and other mobile equipment.
This page covers the following models: SDY1A3616L168, SDY1B209.5L332, and the full SDY series range.
Technical Specifications (Bulleted List)
SDY Series General Specifications
Series: SDY Series (SDY1 sub-series)
Pump Type: External gear, high-pressure
Displacement Range: 16 – 36 cc/rev
Rated Pressure (SDY1): 20.6 MPa (max)
Rated Pressure (select models): 24.5 MPa
Body Material: Cast iron
Fluid Type: Petroleum-based hydraulic oil
Primary Application: Forklifts, wheel loaders, construction machinery
SDY1A3616L168
Model Code: SDY1A3616L168
Cross-Reference: 5S2/49001TCM / HPM 403-40168
Displacement: 36 cc/rev
Rated Pressure: 20.6 MPa
Impact Fatigue Test Pressure: 24.5 MPa
Body Material: Cast iron
Rotation: Right-hand (standard)
SDY1B209.5L332
Model Code: SDY1B209.5L332
Displacement: 20.95 cc/rev
Rated Pressure: 20.6 MPa
Impact Fatigue Test Pressure: 24.5 MPa
Body Material: Cast iron
Rotation: Right-hand (standard)
Key Technical Advantages
1. Exceptional Durability and Impact Resistance
The SDY series has passed 1 million impact fatigue tests at 24.5 MPa high-pressure conditions. This rigorous testing standard ensures long-term reliable operation in mobile hydraulic applications such as forklifts and loaders, where frequent start-stop cycles and severe load fluctuations are common—significantly reducing unplanned downtime.
2. High-Strength Cast Iron Body Construction
The cast iron body combined with precision machining provides superior rigidity and deformation resistance compared to all-aluminum designs. Cast iron’s excellent impact resistance and dimensional stability make it ideal for high-pressure, high-shock-load construction machinery applications.
3. High Volumetric and Mechanical Efficiency
Through precision gear mesh design and optimized axial clearance compensation technology, the SDY series simultaneously maintains high volumetric and mechanical efficiency. Higher efficiency means lower power loss and reduced oil temperature rise, contributing to extended overall hydraulic system life.
4. Long-Life Wear-Resistant Bearings
High wear-resistant bearings maintain non-seizing performance even under high-pressure, high-speed operating conditions. Extended bearing life directly improves overall pump reliability and maintenance intervals, reducing total cost of ownership.
5. Lightweight Compact Design with Low Noise Operation
The pump body incorporates aluminum alloy components with high-precision formed design, achieving weight reduction and compactness without compromising strength. Optimized gear tooth profiles and precision manufacturing effectively reduce operating noise, making it particularly suitable for noise-sensitive indoor working environments.
Application Areas
Forklift hydraulic systems – preferred hydraulic power source for 1–3.5T electric and internal combustion forklifts
Wheel loaders – working hydraulic systems, steering hydraulic systems
Industrial vehicles – material handling equipment, stackers, scissor lifts
Agricultural machinery – tractors, combine harvesters
Construction equipment – mini excavators, skid steer loaders
Expert Maintenance Tips
Model Code Interpretation: In SDY1A3616L168, “SDY1” indicates the SDY1 sub-series, “A” indicates the series version, “36” indicates 36 cc/rev displacement, “16” indicates 16 mm gear width, and “L168” indicates left-hand rotation (counter-clockwise viewed from shaft end). Understanding the code ensures correct selection and parts procurement.
Rotation Direction Verification: Confirm pump rotation matches system requirements before installation. Suffix “L” indicates left-hand (counter-clockwise) rotation; “R” indicates right-hand (clockwise) rotation. Incorrect rotation swaps suction and pressure ports, potentially damaging the pump.
Fluid Cleanliness Management: Maintain system fluid cleanliness to ISO 4406 18/16/13 or better. Gear pumps are sensitive to fluid contamination—install a suction filter with minimum 100 μm rating.
Inlet Line Negative Pressure Control: Inlet absolute pressure must not fall below 0.8 bar (vacuum not exceeding -0.2 bar). Use piping no smaller than the inlet port size and minimize elbows to prevent cavitation damage.
First-Start Priming: Fill the pump cavity with hydraulic oil from the outlet port before first start-up. Running dry or with trapped air will cause severe gear and bearing damage.
Regular Inspection: Inspect pump operating condition every 2,000 operating hours. If system pressure drops, flow decreases, or abnormal noise occurs, promptly inspect gear pairs and bearing wear.
