What Is a Piezometer?
Pressure gauge is an instrument used to measure rolling pressure on the rolling mill of the metallurgical industry. It is a key device to realize the automation of the rolling mill and the automatic control of the thickness of the steel plate. device.
- A manometer is a component used to measure and indicate the rolling pressure. It can be placed between the depressing screw and the upper support roller bearing seat. Considering the effect of frequent movement on the fixed measurement circuit, some are installed under the lower support roller bearing seat. The manometer is sealed well to prevent corrosion by water and scale. It is also placed on top of the depressing nut.
- The pressure gauge plays an important role in the operation of the modern hot strip mill. It is an important parameter in the automatic thickness control system. According to the value of the detected value, the signal is input into the automatic thickness control system To adjust the reduction and control the thickness of the strip. It is also a safety indication signal for the rolling mill. When the indicated rolling force is greater than the specified load, the operator can take measures to prevent equipment accidents. [2]
- Pressure gauges are also commonly called indenters. There are many types, mainly due to the types of sensor elements that are converted from mechanical parameters to electrical parameters. In the measurement of rolling pressure, resistance strain type and piezomagnetic type are widely used. Species. The working principle of the resistance strain type is based on the strain effect of the metal conductor, that is, the resistance of the conductor changes with the amount of mechanical deformation, and the output power is small. Usually it needs to be enlarged to indicate, and the anti-interference ability is relatively poor. There are not many applications for indenters. Piezomagnetic sensor elements use the physical effects of ferromagnetic materials (magnetoelasticity): the effect of stress on magnetism, which converts the measured force into electrical parameters. Compared with resistance strain type, inductive type, capacitive type, voltage type and other sensing elements. It has the advantages of high output power, no amplifier, strong anti-interference ability, high accuracy, good linearity, and small dynamic response time (about tens of milliseconds). In particular, it can run for a long time in harsh environments such as dust, water, and corrosive gas, and is easy to maintain and have a long life. Therefore, it is widely used in rolling mill pressure measurement.
- Piezomagnetic force and load cells are based on the principle that magnetic materials have a magnetoelastic effect (that is, the permeability in the direction of the force will change), which converts force or weight into a primary and secondary transformation of electrical signals proportionally Device.
- For a manometer, the greater the pressure applied, the greater the induced electromotive force generated. By sending this induced electromotive force to a secondary meter, a linear relationship between force or weight and voltage (or current) can be established.
- Piezomagnetic sensor element is composed of many cold rolled silicon steel sheets, and the sheets are bonded with epoxy resin. The shape of the punch for measuring tens of tons to thousands of tons is shown in the figure below. It consists of four units, each unit has four small holes and two large holes. The large holes are used to pass the fixing screws and small holes. For winding coils.
- Large tonnage piezomagnetic pressure gauges mostly adopt the structure shown in the figure below. The pressure measuring element is placed in a rectangular steel casing, and it is separated from the casing by an epoxy phenolic glass cloth plate. The side of the case leads out. The upper cover plate and lower bottom plate, also called force transmission plate, should have a certain degree of hardness, strength and flatness in machining. The contact surface with the load cell should have a surface finish of 7 or more to make the contact uniform. The pins on the base plate are used to locate the manometer.