Mid-West Instrument

Mid-West Instrument, located in Sterling Heights, MI is one of the leading designers and manufacturers of differential pressure gauges and switches in the U.S.

Mid-West® Instrument was founded based on innovation back in 1958. At that time a customer approached Mid-West® Instrument with the need for monitoring pressure drop across a filter. The founders, a group of engineers, developed the model 120 differential pressure gauge. It was then a heritage of working with customers to solve their application needs was born. A second customer approached Mid-West® Instrument with the need for a leak detection gauge, the founders again developed a solution with the model 109 which was based on differential pressure. At this point Mid-West Instrument set out to find more customers with applications that required solutions.

Over the years the product line expanded and as applications warranted, the materials of construction expanded. Applications included all manner of monitoring pressure drop across filters from compressed air, water, lube oil, fuel oil to Natural Gas. Applications for simple indicators rather than differential pressure gauges led to a line of differential pressure indicators for direct mount onto filters rather than through instrument tubing. Complicated applications such as indicating flow from pressure drop across orifice plates, venturis and averaging pitot tubes as well as Liquid level indication were addressed and solutions were created. Hydronic balancing applications and the testing of backflow prevention assemblies led to the design and development of Portable Differential Pressure Instrument Test Kits.

The addition of alarm switches and transmitters to the product line led to the development of switch and transmitter designs to meet the needs of hazardous locations and explosion risk areas which bear national and international certification marks from CSA, UL, ATEX, IECEx, and/or KOSHA.

Primary Activity

Designer and manufacturer of pressure gauges and switches.