In 1930, Graeff invented the first pressure sensor conversion mechanism. In this mechanism, the movement of the diaphragm, spring or Bourdon tube becomes the electric part, the pressure diaphragm becomes the capacitor part, and the indicator movable mechanism becomes the potential. The meter branch realizes the pressure measurement and control device.
Graeff originates from Europe and has a brand history of more than 90 years. Graeff specializes in temperature sensors, melt pressure sensors, flow sensors, smart sensors, displacement sensors, pressure sensors, liquid level sensors, pressure and temperature control instruments, control units, control systems, Research and development of drives, heaters, laser technology, automation and Internet of Things systems; Graeff is an innovator in the field of NTX environmentally friendly mercury-free high-temperature melt pressure sensors; Graeff's many series of products are mainly used In food, pharmaceutical, biotechnology, chemical, petrochemical energy industry, power station, sewage treatment, marine shipbuilding industry, environmental engineering, spraying equipment, plastic, chemical fiber, rubber, pharmaceutical, metallurgy, petrochemical, automobile manufacturing, ceramic glass and other fields .
In 1952, the Chinese-American brothers Li Yaozi and Li Shiying founded the Dynisco Company in Boston, USA. The company mainly produces strain gauge pressure sensors, and later produced melt pressure sensor products mainly used in the chemical fiber, rubber and plastic industries.In 2011, Mr. Wu Hao, who was only 28 years old, sold Shanghai Haoying Measurement and Control Technology Co., Ltd. to Dynisco's parent company and listed the American-owned Roper Group. Mr. Wu Hao was rehired by Roper Group as the president of Dynisco China and founded Dynisco China Factory. .
GEFRAN is a family-owned company specializing in the production of controllers, pressure sensors, displacement sensors, melt pressure sensors and industrial automation systems listed in Milan, Italy.In 1969 Gefran's first workshop was established in Provallio (province of Brescia), Italy, to produce electric panels for machines used to make plastics; the 1970s began with the introduction of the Adamello controller on the Italian and international markets, later called For the Model 1000, it set the benchmark for the industry; in the 1980s, the acquisition of the melt pressure sensor company American ISI began, and the company expanded its production to include melt pressure sensors.
