The first domestic large-scale weighing instrument automatic loading temperature and humidity test device was successfully developed

A few days ago, the Chinese Academy of Metrological Sciences successfully developed the first large-scale automatic weighing temperature and humidity test device in China, and passed the expert appraisal. The device can automatically realize the weighing performance test of large-scale weighing instruments under temperature and humidity conditions through the robot loading and unloading system without disassembling the weighing instrument. The overall technical indicators are better than foreign existing devices, which greatly improves the capacity of the weighing instrument performance testing system in China.

Electronic pricing scales, electronic truck scales, railroad scales, quantitative packaging scales, port scales ... A wide range of weighing instruments are closely related to people's production and life. Whether the quality of weighing instruments is qualified is very important for maintaining market economic order and trade fairness. effect. Weighing performance test including weighing performance test, repeatability test, tare test, etc. is the main means to ensure accurate measurement and qualified quality of the weighing device.

It is understood that, in accordance with the relevant national weighing instrument verification regulations, in addition to the normal temperature test, the performance evaluation test of the weighing instrument also needs to be performed under temperature and humidity conditions. In order to complete the test under temperature and humidity conditions, the module method was used in the past, that is, the large scale weighing instrument was dismantled and moved into the temperature and humidity test box, and then the testers analyzed and tested each component separately. However, the module method is not only cumbersome, but the tester entering the temperature and humidity test chamber will affect the reliability of the test results. At the same time, the high and low temperatures of up to 40 ° C and the lowest -10 ° C and a relative humidity of 85% in the test chamber also make it difficult for testers to complete linear and repeatable tests such as loading and unloading of weights. The lack of performance evaluation test capability for large scales has had a serious impact on China's foreign trade, scale evaluation tests and international mutual recognition. The large-scale weighing instrument automatic loading temperature and humidity test device developed by the Chinese Academy of Metrology has solved this problem well.

According to the head of the project, Wang Jian, Director of the Mass Density Research Office of the China Academy of Metrology, the device is mainly composed of an independently developed robot loading and unloading system, a temperature and humidity test chamber, and an electric pallet truck. The robot loading and unloading system can complete the 10-stage load process backhaul test (of a temperature or wet hot spot) in 12 minutes. Without the need for a tester to enter the temperature and humidity test chamber, the instrument can be adjusted under various temperature and humidity conditions. The scale evaluation test greatly shortens the test time of large scales. At the same time, the drive and electrical components are installed outside the temperature and humidity test chamber, which effectively avoids the influence and damage of temperature and humidity conditions on the long-term stability and reliability of the equipment.

Compared with similar technologies at home and abroad, the device adopts electromechanical integration design technology, the hardware structure is novel, the special-shaped weight group is designed with precision, the combination method is scientific and reasonable, and the software function is complete. At present, the test device system runs smoothly and reliably. It can provide a special temperature and humidity test environment for large-scale, special, and special-shaped weighing devices of 300 to 3000 kg to carry out type evaluation tests such as weighing performance tests, repeatability tests, and peeling tests. The uncertainty is better than 5 × 10-6.

According to industry insiders, the establishment of a large-scale weighing instrument automatic loading test device has improved China's weighing measurement and inspection capabilities, and has met the international legal measurement organization (OIML) international recommendations on weighing instruments and the OIML type evaluation multilateral recognition framework agreement (MAA) test technical requirements With China's weighing instrument measurement and testing capabilities entered the international advanced ranks.