LZ is the use of metal tube variable area measuring principle for continuous measurement of volume flow in closed conduits of liquids and gases. Metal tube with a rugged and reliable, using a wide temperature range, high accuracy, low price, can be applied to a variety of occasions such as flow measurement characteristics. This series of field intelligence indicating type, there is the next entry on the left and lower right out into the side three installation form. It can be widely used in liquid, gas flow measurement defense, chemical, petroleum, metallurgy, electric power, environmental protection, medicine and light industry and other sectors. ? LZ series of metal tube variable area flowmeter, namely in the vertical measuring tube flowmeter, when the fluid flows through the pipe up, the float moves up one position in the lift and float float suffered gravity reach balance, circulation annulus area at this time of the float and orifice (or taper pipe) between constant. Rise annulus area is proportional to the height of the float, which is highly representative of the size of a float flow. When the float moves up and down, in the form of magnetic coupling is passed to an external location indicator, the indicator follows the float moves a pointer, and with the cam plate so that the size of the pointer indicates the linear flow rate values. Electric remote type is a pointer while directing the flow through the angular displacement sensor and electrical transmission circuit, the flow value accurately converted into a standard 4-20mA signal.