Choose a hydraulic cylinder by defining the machine function first, then verifying force through the real linkage, available pressure and flow, stroke and installation lengths, rod stability, mounting, load direction, speed, duty cycle, environment and safety controls. Bore alone is not a complete selection method.<\/p>
This article provides general engineering guidance. Machine-specific instructions, controlled drawings, applicable safety procedures and qualified personnel take precedence whenever a cylinder supports, moves or restrains a load.<\/p>
Define the load throughout motion, including breakaway, acceleration, friction, shock and external forces. Translate that machine load through the linkage to determine force at the cylinder pin.<\/p>
The worst cylinder force may occur at an unfavorable linkage angle rather than at maximum payload. Review extension and retraction separately because their effective areas differ.<\/p>
Bore primarily influences hydraulic force and oil volume. Rod diameter influences tensile stress, compressive buckling, stiffness, bearing load and the difference between extension and retraction area.<\/p>
A larger bore may increase force but also increases oil demand and can reduce speed at fixed flow. A larger rod may improve compression stability while reducing retraction force.<\/p>
Required machine travel must be converted into cylinder stroke while respecting physical stops and tolerance. Confirm pin-to-pin or mounting-face lengths at both retracted and extended positions.<\/p>
Choose mounting styles that allow intended motion without forcing side load. Pin alignment, bearing width, clearances, hose movement and service access all affect reliability.<\/p>
Use normal and peak circuit pressure with an appropriate design review; do not select from relief pressure alone. Verify pump flow, valve capacity, port size and acceptable speed in both directions.<\/p>
Fast or heavy motion requires attention to stopping energy, cushioning, load-control valves and machine structure. The cylinder, circuit and frame operate as one system.<\/p>
Fluid, temperature, contamination, corrosion, outdoor exposure, washdown and duty cycle guide seal, coating and material choices. Maintenance access and spare-parts strategy matter for lifecycle cost.<\/p>
An OEM RFQ should include drawings, tolerances, inspection points, traceability, test pressure or functional test requirements and acceptance criteria. Unverified marketing claims should not replace measurable requirements.<\/p>
| Selection step<\/th> | Primary question<\/th> | \u0645\u062e\u0631\u062c<\/th><\/tr><\/thead> |
|---|---|---|
| Function and geometry<\/td> | What force is required at each position?<\/td> | Cylinder force profile<\/td><\/tr> |
| Pressure and area<\/td> | What bore provides force with margin?<\/td> | Preliminary bore<\/td><\/tr> |
| Rod and mounting<\/td> | Will compression, side load and alignment be controlled?<\/td> | Rod and interface design<\/td><\/tr> |
| Flow and motion<\/td> | Can the circuit achieve safe speed and deceleration?<\/td> | Port, valve and cushion requirements<\/td><\/tr> |
| Environment and validation<\/td> | How will the unit survive and be accepted?<\/td> | Materials, seals, coating and tests<\/td><\/tr><\/tbody><\/table><\/figure>Information required for an OEM quotation<\/h2>Frequently asked questions<\/h2> |