Shanghai Automation Instrument No. 4 Factory was founded in 1950. It is a key enterprise of the Ministry of Machinery Industry specializing in the production of pressure detection instruments and pressure measuring instruments. There are currently 645 employees, including more than 180 professional and technical personnel and 12 senior engineers. The factory covers an area of ??more than 12,000 square meters and a building area of ??22,000 square meters. It is one of the largest production bases for pressure instruments in my country. The registered trademark "Baiyun Brand" ". Baiyun brand series pressure gauges are widely used in petrochemical industry, metallurgical mining, transportation, power stations, textiles, food, scientific research and other industries. The products are famous for their high precision, variety and excellent quality, and have won a high reputation. Exported to Europe, America and Southeast Asia. The products include six categories: special pressure gauges, pressure measuring instruments, pressure controllers, pressure transmitters, general pressure gauges and special pressure gauges, and computer real-time control systems, with more than 100 varieties and more than 4,000 specifications.

In recent years, with the development and application of high and new technologies, Shanghai Automation Instrument Factory No. 4 has been committed to the development of new products while upgrading old products. National-level new product - all-stainless steel series pressure gauges, with basic quality performance, function-price ratio, and variety range leading the country. In 1995 and 1996, it was continuously recommended as a famous brand product in Shanghai. The PM10 pressure transmitter and derivative products introduced from the UK quickly won the domestic market. The CY series of small pressure sensors produced by the Fourth Factory are key components of the Long March series and various types of rocket bodies. This component has been foolproof in the launches of previous satellites and strategic missiles, and has made great contributions to my country's rocket launch and missile research. For his contribution, he has been awarded many times by the Commission of Science, Technology and Industry for National Defense. Our factory has entered the high-tech industry in Shanghai and passed the ISO9001 quality system certification in 1996.