What is a horizontal rolling mill?2021-09-16
At present, the horizontal rolling mill is the main equipment of small and medium-sized steel rolling enterprises in China. It is mainly used to produce all kinds of section steel rebar, wire rod, deformed bar, angle bar, and small steel billets. Its main features are: 1) A set of rolling mills is driven by a motor. The roll speed of each mill is the same, and the rolling speed cannot be increased with the increase of the length of the rolled piece, so the output is low, and the labor productivity is low. 2) That structure of the rolling mill is generally three-roll type or two-roll alternating type 3) That operation mode of the rolling mill is shuttle rolling or loop roll. Each rolling mill can roll several passes, with flexible deformation, strong adaptability, a wide range of product varieties, and easy operation. 4) That mill has simple equipment, low investment, and fast plant construction
Importance of Cooling System for Medium Frequency Furnace2021-09-16
During the working process of the medium frequency furnace, the components carrying large currents, such as electric furnace coils, yokes, water-cooled cables and power cabinets, all need water cooling. The cooling water system is the key system in the medium frequency furnace device and an important component to ensure the normal operation and safe operation of the equipment. First, the equipment cooling requirements are as follows: 1, According to the equipment “instructions” provisions of the water supply pressure, flow water supply. 2. Use industrial demineralized water as far as possible-PH value: 7.2 ~ 8.0 3. It is better to supply water from special cooling towers for power supply cooling and furnace body cooling respectively. In particular, the power supply shall be cooled by a water-water exchanger or closed cooling tower. 4. As the acidity of water and the content of calcium and magnesium impurities gradually increase, corrosion or scale will occur, affecting the heat dissipation effect and service life of the heat exchanger. The cooling equipment should be cleaned in time. 5. Sensors and water-cooled cables are equipped with pressure gauges, temperature meters, water pressure regulating switches, and other components to monitor the cooling water system at the entrance and...
How does an intermediate frequency heating furnace work2021-09-15
Intermediate frequency heating furnace is induction heating equipment for the purpose of heating metal forging or tempering heat treatment. It is generally used for heating before forging and the heating temperature is 1200 degrees, while the heating temperature for tempering heating is generally within 1000 degrees. This intermediate frequency heating application determines that the heating principle of an intermediate frequency heating furnace is only for heating purposes and cannot melt metal. Therefore, if the heating furnace in the structure, in principle is different from other forms of heating furnace, next we will talk about if heating furnace principle. 1. The principle of intermediate frequency heating furnace is based on electromagnetic induction heating and follows the electromagnetic effect theory, such as electromagnetic ring effect, skin effect, sharp Angle effect, proximity effect, diathermy effect, conduction effect, etc. 2. intermediate frequency furnace is mainly composed of variable frequency device and induction coil, power frequency 50 Hz alternating current frequency conversion device would turn into intermediate frequency 100 Hz – 10000 Hz of alternating current, the three-phase alternating current into direct current (dc) after rectifying power frequency, and then laid adjustable intermediate frequency electric current, direct current supply by the capacitor and inductor in...
The fault analysis and maintenance process of medium frequency heating furnace.2021-09-14
When the medium frequency heating furnace is started, the given voltage is suddenly applied. Because there is no voltage feedback, the output of the voltage regulator increases rapidly. Due to the drift of control parameters, the current feedback coefficient is reduced. The same if the current is given, the instantaneous current of if the device is relatively large, resulting in impulse current. Only when the voltage loop is overshoot, the output current begins to decrease, which is finally determined by the load. Because of the large reactance in the medium frequency furnace, the system response is slow. With the increase of the given voltage, the impact current is larger, and the impact on the thyristor is also large, which accelerates the degradation of the thyristor, resulting in the fatigue breakdown of the thyristor. With the aging of components and the parameter drift of the analog control system, the lead angle triggered by thyristor in the inverter control circuit becomes larger (42.8 °), and the power factor is low (0.733). Even if the same intermediate frequency voltage and current are output, the active power output of the intermediate frequency heating furnace is not high and the heating effect is poor. Under...
What are the daily maintenance of medium frequency furnaces?2021-09-13
In order to ensure the working effect of the medium frequency furnace and prolong the service life of the medium frequency furnace, the medium frequency furnace should be regularly maintained and inspected. Daily maintenance can be carried out from the following aspects: 1. Check and clean the radiator to maintain a high-efficiency cooling effect, and carry out pickling when necessary; 2, Check whether the water cooling system is blocked and leaking phenomenon, whether the water pressure relay is sensitive, inlet water temperature difference should not be greater than 35 ℃; 3, Check the induction coil insulation and whether there is a water leakage phenomenon; 4, Check whether the wires and switches are damaged; 5, Check and clean the water tank, check the drain valve, and remove certain sewage to prevent scaling; 6. Clean the oil stains and dust of all electrical components and other equipment, and use fans or leather tigers to clean up the dust; 7. Check whether each wiring screw is tightened to ensure good contact. 8. Check thyristor, electrical circuit bus, transformer, and each line segment for overheating.
What energy loss is metal induction heating2021-09-13
Energy losses, during induction heating: 1, The energy loss is caused by the current flowing through the copper wire of the sensor. 2, heat loss from heated blanks and thermal insulation through the sensor; 3, heat loss from the heated blank into the surrounding medium. The energy lost in the first two forms is the main part of all the losses, which is taken away by the cooling water flowing through the sensor copper tube and can be obtained by calculation and test methods. The third form of energy is taken away by the flowing air. Its values are difficult to obtain by calculation and testing methods.