In the daily procurement of spare parts, on-site maintenance replacement and inventory sorting work, it is often necessary to quickly distinguish brand-new qualified thermocouples from aging and performance-declined old products. Mastering simple and practical identification skills can effectively avoid mixing old and new accessories, prevent aging products from being put into use again, and reduce various quality hidden dangers and production failures caused by the reuse of expired accessories.
The first is intuitive appearance observa
The second is structural flexibility and firmness test. The wire body of new thermocouples has good bending toughness, which can be bent repeatedly within a reasonable angle without wire core fracture and internal loose noise. The thread structure is intact, and the clamping is tight and smooth during installation. While aging thermocouples become brittle overall after long-term high-temperature baking, the wire body is easy to break when bent slightly, the internal structure is loose, and there will be abnormal shaking sound when shaking gently. The fixing thread is worn and slippery, which cannot achieve good anti-loose fixing effect.
The third is temperature response speed comparison test. Under the same heating condition, new high-quality thermocouples can sense temperature changes quickly, the temperature rise and fall data feedback is sensitive and rapid, and the numerical fluctuation is stable without sudden jump. Aging thermocouples have obvious sensing lag, slow temperature rise feedback, large data floating range in constant temperature state, and poor stability, which cannot keep consistent with the real temperature change rhythm.
The fourth is precision error detection and judgment. Use professional temperature comparison equipment to carry out simultaneous temperature measurement test. The temperature measurement error of new qualified products is controlled within the industry standard range, and the repeated measurement data is highly consistent. The temperature drift value of aging products is too large, the error exceeds the allowable range, and the data difference of multiple measurements is obvious, which cannot meet the precision requirements of formal production temperature control.
In addition, we can also distinguish through production batch numbers and service cycle records. Regular manufacturers will mark the production date and batch information on the product accessories. Combined with the actual use time on site, we can accurately judge the remaining stable service life of thermocouples. In actual accessory management, strictly separate new spare parts and recycled old accessories, eliminate the random reuse of aging thermocouples from the management level, ensure that all thermocouples used in the production line are in the best performance state, and effectively guarantee the stability of hot runner temperature control and injection molding product quality.
