| Continuous hydraulic pressure | Confirm that the actuator’s continuous working pressure is not merely a short-term peak rating. | 160–210 bar continuous rating, according to the forklift hydraulic circuit. | Technical datasheet, stamped drawing, pressure-rating statement, and test report. | Choose a rating equal to or above the system relief-valve setting, with a documented safety margin. |
| Proof and burst pressure | Separate proof pressure from maximum working pressure and burst pressure. | A proof value is often specified above working pressure; the exact multiplier must be confirmed in the approved design standard and drawing. | Hydrostatic proof-test procedure, recorded test pressure, hold time, and acceptance criteria. | Reject quotations that list only one pressure value without defining its meaning. |
| Push-force capacity | Check piston diameter against the required lifting or tilting force. | Theoretical extension force: F = p × πD² ÷ 4, where p is pressure and D is piston diameter. | Force calculation, bore and rod dimensions, efficiency assumptions, and load-cycle data. | Allow for friction, side loading, dynamic loads, and the difference between static and working load. |
| Example force calculation | Use nominal pressure and bore size to compare actuator sizing. | 50 mm bore at 160 bar ≈ 31.4 kN; 60 mm bore at 180 bar ≈ 50.9 kN; 63 mm bore at 200 bar ≈ 62.3 kN; 70 mm bore at 210 bar ≈ 80.8 kN. | Supplier calculation using the same pressure, bore, and unit system. | Treat these as theoretical extension forces; actual output is lower because of friction and operating conditions. |
| Retract-force capacity | Account for the rod area when the actuator operates in retraction. | Retract force: F = p × π(D² − d²) ÷ 4, where d is the rod diameter. | Rod diameter, retract-force calculation, and measured performance data. | Verify both directions whenever the actuator controls mast tilt, fork positioning, or attachment movement. |
| IP65 enclosure protection | Confirm the IP rating applies to the complete actuator assembly, including connectors and cable exits. | Under IEC 60529, IP6X indicates dust-tight protection; IPX5 indicates protection against water jets. | IEC 60529 test report or certificate identifying the tested configuration. | Suitable for dusty environments and ordinary water-jet exposure when the installation is correctly sealed. |
| IP66 enclosure protection | Verify resistance to more powerful water jets than IP65. | Under IEC 60529, IP6X indicates dust-tight protection; IPX6 indicates protection against powerful water jets. | Test report showing the water-flow and exposure conditions used for the enclosure. | Preferable for outdoor forklift washing areas and equipment exposed to heavy spray. |
| IP67 enclosure protection | Confirm whether temporary immersion protection is required for the complete assembly. | Under IEC 60529, IP6X indicates dust-tight protection; IPX7 indicates protection against temporary immersion, typically up to 1 m for 30 minutes under the test condition. | IEC 60529 immersion-test report, including mounting orientation and cable-entry configuration. | Select only when temporary immersion is possible; IP67 does not automatically replace every higher water-jet requirement. |
| Sealing and cable entry | Inspect shaft seals, static seals, connector seals, breather arrangements, and cable glands. | Sealing materials must be compatible with the specified hydraulic fluid, temperature range, and cleaning chemicals. | Seal-material declaration, connector specification, cross-section drawing, and ingress-test configuration. | Do not accept an IP rating based only on the actuator body if the connector or cable gland is less protected. |
| Rod and tube durability | Check surface treatment, corrosion resistance, alignment, and protection from side loads. | The required treatment depends on salt exposure, outdoor use, impact risk, and cleaning chemicals. | Material certificates, coating or plating specification, salt-spray data where applicable, and fatigue-test results. | Use mechanical guides or spherical mounting where the application can create lateral loading. |
| Leakage and cleanliness | Verify external leakage, internal bypass, flushing, and contamination control. | Acceptance limits should be defined for static leakage, dynamic leakage, and pressure holding. | End-of-line test records, cleanliness target, flushing method, and sample inspection report. | Prioritize documented test records over general statements such as “100% tested.” |
| Temperature and hydraulic-fluid compatibility | Match seal and coating materials to the actual operating environment. | Confirm minimum and maximum operating temperature, fluid type, viscosity range, and cold-start conditions. | Operating-limit sheet, seal-material declaration, and fluid compatibility statement. | Request application approval for biodegradable or fire-resistant fluids rather than assuming compatibility. |
| Functional and endurance testing | Confirm that testing represents the forklift’s load, speed, stroke, and duty cycle. | Test conditions should include rated pressure, operating speed, stroke length, cycle count, temperature, and load direction. | Validation plan, endurance report, failure criteria, and production-control records. | Compare suppliers using identical test conditions and require corrective-action records for failures. |
| Dimensional interchangeability | Check retracted length, stroke, mounting points, port size, rod thread, and installation envelope. | All dimensions must match the approved forklift interface drawing and tolerance requirements. | Controlled 2D drawing, 3D model, tolerance table, and first-article inspection report. | Require written approval for any dimensional substitution, even when pressure and IP ratings are equivalent. |
| Supplier quality controls | Evaluate traceability from raw material through final pressure and ingress testing. | Minimum documentation should cover incoming inspection, process control, calibration, final inspection, and nonconformance handling. | Quality manual, calibration records, control plan, inspection report, and batch traceability sample. | Use a pre-production sample and an on-site or third-party inspection before volume approval. |