Ninghe Office Chair Testing

Ninghe office chair testing primarily involves performance evaluations of key components such as stability, caster durability, and gas springs. Details are as follows:

Stability Testing
According to the EN1335 standard, testing institutions simulate the critical point of imbalance during real-world use by applying standardized force values and position settings. In static testing, a rigid loading block simulates human body weight (e.g., a standard value of 75 kg), which is fixed to a designated area on the seat surface. A force gauge then slowly applies a horizontal push force until it reaches 250 Newtons, at which point the application stops to observe whether the chair legs lift off the ground. If the chair legs remain on the ground, static stability is deemed qualified. Dynamic testing simulates the impact force when a user suddenly leans back: after the loading block is released, it swings freely to strike the chair back, and sensors record displacement and force data during the impact to evaluate the chair's resistance to tipping. Both tests must be conducted on a dry, flat testing platform to eliminate environmental interference.

Caster Durability Testing
Testing institutions use a dedicated testing platform to simulate long-term rolling scenarios. The test chair is fixed at the center of the platform, and the caster contact surface bears a specified load (e.g., 100 kg). A pneumatic cylinder drives the platform to rotate alternately at a speed of 10 revolutions per minute, causing the casters to continuously perform reciprocating linear motion. The complete test cycle consists of 72,000 cycles, during which the following indicators must be monitored:

• Increase in rolling resistance: A force sensor records the rolling resistance during the initial and final cycles. If the resistance increase exceeds 20%, the casters are deemed to have failed;
• Rotation deviation angle: An angle gauge measures the offset of the caster's rotational axis. A deviation angle exceeding 5° is considered unqualified;
• Component detachment: Checks are made for looseness or detachment of components such as wheel hubs and bearings.

Gas Spring Performance Testing
Testing objects include gas spring monomers, lifting column assemblies, and complete chair assemblies:

• Monomer testing: Focuses on evaluating support force (which must meet a ±5% deviation from the design load), sealing (detected by a helium mass spectrometer leak detector with a leakage rate ≤ 1×10⁻⁶ Pa·m³/s), and lifespan (after simulating 100,000 lifting cycles, the performance degradation rate must be ≤ 10%);
• Assembly and complete chair testing: Focuses on lifting smoothness (recorded by a displacement sensor counting the number of stutters during lifting), abnormal noise (noise levels ≤ 45 dB detected in a quiet environment), and fit quality with the seat surface and chassis (e.g., gap uniformity ≤ 0.5 mm);
• Material testing: Extends to the physical and chemical properties of key components, such as the coating thickness of the piston rod (which must be ≥ 8 μm), the tensile strength of the cylinder tube steel (≥ 450 MPa), and the Shore hardness of the rubber seal ring (60 ± 5 HA).

All the above tests must be conducted in a constant-temperature and constant-humidity laboratory to ensure data comparability.