Electromagnetic flowmeter classification

　　1. General type: In metallurgy, petrochemical, papermaking, printing and dyeing textile, water supply, sewage treatment and other industries, separate medium and large diameter flange connection methods are generally used; in medicine, biology, fine chemical and other industries, micro-diameter and small-diameter instruments are often used, and integrated clamp connection or threaded connection is applicable to more places. 

　　2. Explosion-proof type is used in places with explosive and flammable atmosphere. Since most EMFs have large excitation current energy, they are usually designed as flameproof, sand-filled, cast-sealed and airtight types. However, some EMF excitation power is greatly reduced now, and there are also intrinsically safe types, which are previously called safe spark types. The flow sensor part and the conversion part are conditionally integrated and all installed in the hazardous area. 

　　3. Hygienic cheese, food, medicine, biochemistry and other industries require regular steam sterilization. The sensor should be easy to disassemble and clean. The connection parts with the pipeline should adopt the hygienic structure specified for quick loading and unloading. The materials in contact with the liquid should be non-toxic and harmless. 

4. Water-resistant type This type of sensor is used in manholes installed under the ground and can withstand short-term water immersion, which is equivalent to the shell protection level IP67 or NEMA6; there are also those equivalent to the protection level IP68, which can withstand long-term diving. 

　　5. Submersible type This type of instrument is used to measure the flow rate of waterways flowing naturally under the free water surface of open channels or non-full pipe culverts, such as industrial drainage and sewage. The sensor is installed under the interception baffle of the open channel and is immersed in water for a long time. When used for large flow, multiple diversion models with the same shape as the sensor can be installed to expand the flow rate.