YUKEN A70、A90 Piston Pump
1. Product Overview
The YUKEN A70 and A90 series are high-efficiency swash plate type variable displacement piston pumps, developed by YUKEN with unique core technology to meet the industry’s demands for energy saving, low noise and high reliability. As important members of YUKEN’s “A” series piston pumps, these two models are widely applied in various hydraulic systems of industrial machinery, featuring stable performance, strong adaptability and flexible control modes. The A70 and A90 pumps are designed for medium and large flow hydraulic systems, with slight differences in displacement and installation dimensions to match different load and space requirements.
2. Key Specifications
| Specification Item | A70 Series | A90 Series |
|---|---|---|
| Geometric Displacement | 70.0 cm³/rev (4.27 cu.in./rev)[1[1]] | 91.0 cm³/rev (5.55 cu.in./rev)[1[1]] |
| Minimum Adjustable Flow | 30 cm³/rev (1.83 cu.in./rev)[1[1]] | 56 cm³/rev (3.42 cu.in./rev)[1[1]] |
| Operating Pressure | Rated: 25 MPa (3630 psi); Maximum Intermittent: 28 MPa (4060 psi)[1[1]] | Rated: 25 MPa (3630 psi); Maximum Intermittent: 28 MPa (4060 psi)[1[1]] |
| Shaft Speed Range | 600 – 1800 r/min (no load to full load)[1[1]] | 600 – 1800 r/min (no load to full load)[1[1]] |
| Approximate Mass | 58.5 – 72.5 kg (129 – 160 lbs)[1[1]] | 72.5 – 93 kg (160 – 205 lbs)[1[1]] |
| Mounting Type | Flange mounting (F type) or foot mounting (L type) available[4[4]] | Flange mounting (F type) or foot mounting (L type) available[4[4]] |
| Rotation Direction | Clockwise (R type, viewed from the shaft end) as standard; Counterclockwise available on request[4[4]] | Clockwise (R type, viewed from the shaft end) as standard; Counterclockwise available on request[4[4]] |
| Control Type | Pressure compensator type (code “01”) and constant power control type (code “09”) available; Load sensing control optional[3[3]][4[4]] | Pressure compensator type (code “01”) and constant power control type (code “09”) available; Load sensing control optional[3[3]][4[4]] |
3. Core Features
- High Efficiency & Energy Saving: Under the conditions of 16 MPa (2320 psi) and 1800 r/min, the volumetric efficiency is over 98% and the overall efficiency is over 90%, which effectively saves input power and reduces energy consumption[2[2]]. The sharp cut-off characteristics and low power loss also help reduce oil temperature rise, thus minimizing the capacity requirement of the oil reservoir[2[2]].
- Low Noise Operation: Adopting optimized structural design and precision manufacturing technology, the noise level is significantly reduced, improving the operating environment of the equipment[3[3]][6[6]].
- Strong Pressure Bearing Capacity: The maximum intermittent pressure can reach 28 MPa (4060 psi), which can cope with high-pressure working conditions such as rolling mill pressing systems and blast furnace top equipment[3[3]]. Key components (pistons, cylinder blocks) are made of ausferritic ductile iron or high-strength alloy steel,经过 precision processing and heat treatment, featuring excellent wear resistance and corrosion resistance[3[3]].
- Flexible Variable Control: The pressure compensator control can dynamically adjust the flow according to the load demand to maintain stable system pressure; the constant power control can match the output power with the prime mover power to avoid overload[3[3]][4[4]]. Customized control modes are available to meet different application needs.
- Good Adaptability: Suitable for petroleum-based hydraulic oils (ISO VG 32 or 46), and customized models for special fluids (such as water-glycol, phosphate ester) are also available (note: operating parameters will vary according to fluid type)[1[1]][5[5]]. It has strong contamination resistance and can adapt to harsh industrial environments[3[3]].
4. Installation & Operation Instructions
4.1 Hydraulic Fluid Requirements
Use anti-wear hydraulic oil or R&O (rust and oxidation inhibitor) type hydraulic oil based on petroleum, with a viscosity range of 20 to 400 cSt and an operating temperature range of 0 to 60℃; both requirements must be met simultaneously[2[2]][5[5]]. For special fluids, consult YUKEN sales representatives for parameter adjustments and model selection.
4.2 Contamination Control
Strictly control the contamination degree of hydraulic oil to avoid equipment failure and service life reduction. The oil contamination degree should be maintained within NAS Grade 10[2[2]][5[5]]. The suction port must be equipped with a reservoir type filter of at least 100 μm (150 mesh), and the return line must be equipped with a line type filter of less than 10 μm.
4.3 Mounting Notes
When installing the pump, ensure the filling port is positioned upwards. Use a flexible coupling as much as possible to avoid bending or thrust stress on the shaft; the maximum permissible misalignment is less than 0.1 mm TIR, and the maximum permissible misangularity is less than 0.2°. The height of the pump inlet port should be within 1 meter from the oil level in the reservoir.
4.4 Suction & Drain Piping
The permissible suction pressure at the pump inlet is between -0.16 and +0.5 kgf/cm² (-125 mmHg ~ +0.5 kgf/cm²)[2[2]]. Use pipes with the same diameter as the specified pipe flange for the suction port piping. The drain piping should be installed according to the specifications, ensuring that the pressure inside the pump housing is maintained at a normal pressure of less than 0.1 MPa and a surge pressure of less than 0.5 MPa; the pipe length should be less than 1 meter, and the pipe end should be submerged in oil.
4.5 Start-Up Operation
Before starting the pump, bleed air from the pump case and outlet line to avoid vibration; it is recommended to install an air bleed valve for this purpose[5[5]]. When starting, run the pump at no load first to check for abnormal noise, leakage or pressure fluctuation, and put it into formal operation only after confirming normal operation.
5. Maintenance & Troubleshooting
5.1 Regular Maintenance
- Check the wear of seals every 500 hours, and replace the hydraulic oil and filter element every 2000 hours.
- Regularly monitor the oil level, oil temperature, system pressure, pump vibration and noise, and handle any abnormalities in a timely manner.
- Regularly inspect the variable mechanism, pressure regulating screw and coupling for looseness or damage, and tighten or replace them as needed.
5.2 Common Troubleshooting
- Flow Fluctuation: Check if the control piston of the variable mechanism is scratched; replace the damper or spring module if necessary.
- Insufficient Pressure: Confirm whether the system is operating under long-term overload; avoid the proportion of short-term peak pressure exceeding the standard (it is recommended that a single peak lasts no more than 10 seconds, and the cumulative proportion is no more than 5%).
- Excessive Noise: Check the coupling alignment, suction piping tightness or oil viscosity; eliminate air in the system or replace unqualified hydraulic oil.
- Oil Leakage: Inspect the seal ring for aging or damage, and check the tightness of the pipe connection; replace the seal ring or tighten the connection as needed.
6. Important Notes
- When setting the pressure, ensure that the full cut-off pressure never exceeds the maximum intermittent pressure to avoid component damage.
- If the pump is used at a pressure higher than the rated pressure, the operating conditions will be restricted; for example, when used under the maximum illustrated operating conditions, the intermittent time at maximum flow is limited to less than 1/5 of one cycle time and less than 6 seconds simultaneously.
- The specifications in this document are for petroleum-based oils; for pumps using special fluids, consult the factory or YUKEN sales representative for detailed parameters.
- The pump does not include pipe flange components; order them separately according to the required component number if needed.
- For any customized requirements (such as special control modes, high-temperature seals), contact YUKEN for professional technical support.
