The history of RMG begins at the end of the 19th century. Its origins lie in the "Morell'sche Fabrik" for rotary compressors, which was renamed Hessenwerke Maschinenfabrik in 1911. In 1931, Rudolf Majert took over all shares in the company and renamed it Hessenwerk Rudolf Majert. During this time, gas pressure control valves for the gas industry are also built for the first time.
After the Second World War, larger nominal sizes of gas pressure regulating valves and various safety devices with increased pressure ratings are developed in close contact with the gas industry. In 1964, the company became the property of an industrial group and was continued under the new name RMG Regel und Messtechnik GmbH. The roots of RMG are based on the gas technology coined by Rudolf Majert.