2 Caused by the help of magnetic flux, 5 is caused by the disturbance of the power supply system. 1 Analysis of the cause of the fault Both the power system disturbance and the excitation fault cause the synchronous motor to step out and then jump. After a step-out jump, it will result in the loosening of the stator lashing line, the pouring of hunger, the breakdown of the insulation, and the progress of causing the internal short-circuit and fire of the motor to cause theoretical analysis and practical experience. The cause of these failures is by no means the motor itself, but most of the current equipment used by our factory on the excitation device is a thyristor device. These decoration! There are many defects in the performance of dynamic performance and full-step excitation performance, resulting in many defects in the operation of the motor. For example, a detailed analysis of the shortcomings of its existing devices is used. 1.1 When the motor starts to rotate To achieve 5 off 8 synchronous speed to 1 machine will appear pulse vibration, and more and more intense and obvious, which is 10, the device asynchronous starting circuit design is not reasonable to cause the slip to reduce to a certain degree, the excitation loop induced current In the negative half cycle, the channel is not smooth, and it is in the off-time and on-off phase. It seems that the corresponding excitation winding around the asynchronous drive torque split test mode disappears. As a result, Tuning’s brother's stepping characteristic curves from jump to minute. Therefore, in the latter part of the motor's asynchronous start-up process, the motor reciprocates between them, forming a pulsating component of the torque characteristic, causing the motor to pulsate. In addition, the induced current in the excitation loop is at a constant slip. Under the condition of positive and negative half-wave asymmetry, it is equivalent to the emergence of a DC excitation current in the excitation circuit to make the motor produce a more intense pulse again, due to the poor control circuit design, often appear on the demagnetization silicon conduction value changes , start, resulting in the heart of silicon germanium with burning breakdown, or sudden loss of magnetization in the mustard operation, due to the various reasons mentioned above, making our plant synchronization failure to stop frequently, many motor damage. If the motor positioning pin is loosely displaced, the motor broom rotor asynchronously activates the copper strip to break loose; the stator coil tie-line loosens; the insulation breaks the coil damage and the phenomenon occurs when the excitation circuit induces voltage 12 When the motor has an internal fault or external fault Forced stop excitation devices require good demagnetization performance. The motor is protected from possible harm to protect the safety of the motor and the demagnetization measure adopted by the 101-type excitation device is inverter degaussing. Because its degaussing speed is inhibited by the inverter voltage and cannot be accelerated, the magneto Too slow. itSQ50.7s, KnJi is not reliable enough to play a corresponding role. Therefore, it can not meet the requirements, it is easy to make the motor caused by dark injury 13 when the high-voltage synchronous machine starts, especially the motor with 2500 or more, in the same time pulling the sound is often heard dull by the factory 1; type 1 excitation device full step excitation The circuit is designed to dispense a small number of 12 small 6 through holes to distribute the stress. The first layer of steel welding rods all use magic 08, the first weld between the steel plate and the cast iron, welding edge flute welding meat, after welding, with 0.5 pound hammer evenly hammered meat and steel plate, so that the steel is completely posted Together, and produce appropriate plastic deformation, re-welded between the weld between the steel plate and the plug steel plate on the dispersion of stress holes, the same choice of electrode 2308, edge welding edge hammered welding meat to eliminate welding stress. The welding of the first to the ninth layer of the steel plate is the same as that of the first layer, but the selected electrode is different. The 2308 electrode is used between the steel plate and the cast iron, the process is the same as above, and the welding between the plates and the plug welding are selected. 427 welding music, specification 3.2, welding current 94.2.4 layer welding. In the final layer welding, welding rod selection B308, the same process before, the welding height of about 5 or so, to be processed 5 After welding inspection Angle grinder Polished welding exposed metal luster, bleed test, especially cracks, 6 After the watts processing fuselage watts fracture repair welding, homemade processing equipment on-site processing, the effect of good pregnancy 7 repair effect of the repair of the nitrogen compressor for the factory to save costs 400,000 yuan The nitrogen press into the transport hall so far There have been many inspections of apricots on several occasions. The original cracks have not been expanded. New cracks and other defects have not been found at the repair welding site. The equipment runs smoothly and normally and has reached the designed production capacity. 8 Conclusions Large-scale cast iron pieces can be repaired by welding using cast iron. If the cracks cannot be completely removed, the most effective method for preventing residual crack propagation is to stop the crack arrest tube. It is an effective method to speed up the repair of cast iron to ensure the quality of cast iron repair welding. Then, the position angle of the page 37 is not consistent. 21 The centralized control unit such as the one produced in Changsha replaces the control part of the old device. This type of control unit invests in the water connection and is quick and easy to run. The performance is good, not easy to damage, minimal maintenance, 22 to modify the magnetic circuit to make it a capacitive magnetic flux control loop closed resistance and capacitance, so that the entire fire magnetic excitation circuit inductance 2 improvement and processing process Very reliable, magnetic, can be reduced to a small 12 23 to improve the start-up performance of the synchronous machine, the use of advanced technology means, a complete transformation of the original excitation ugly moving circuit, the secondary start-up circuit of the thyristor in the motor The turn-on voltage at start-up is reduced to the peak value 714. Since the power-frequency rms 5 minimizes the turn-on voltage, the induced current can go through the positive and negative half-cycles to eliminate the phenomenon of pulse wave. After the excitation and normal operation, the thyristor control circuit is completely shut off, thus solving the problem of misfiring caused by misfiring. Through the above technological transformation, the working condition of the synchronous motor has been improved to reduce the motor failure rate to a minimum. Amnesty supply coefficient greatly improved. The long-term safe operation of the device is effectively guaranteed and the country can recover 100,000 yuan for the country each year for millions of yuan to overcome the difficulties brought by the production of the old excitation device. Barbecue Grill Mesh is also called BBQ grill mesh. It is mainly welded by 304 Stainless Steel Crimped Wire Mesh . It has the features of high temperature resistance and easy to clear.
Usage: Filters ,sieve,chemical industry, mine industry, paper-making , etc
Material: SS 201,202,304,304L, 316,316L, 321, 430,ect
Woven style: plain,twill,dutch
Mesh:1-635mesh
Diameter: 0.0008"-0.08"
Packaging Details: inner kraft, outside plastic cloth, put into wooden pallet or case
Features and benefits:
Just wipe clean
Easily cut to fit any grill
Stores easily
Non toxic material is safe for all food
4 year warranty
Veggies won't fall down in the grill
Fish won't stick
BBQ more outside with the Grill Mat
FDA,LGBS approval Barbecue Grill Mesh Barbecue Grill Mesh,Ptfe Fiberglass Barbecue Grill Mesh,Crisp Bbq Cooking Grill Mesh,Stainless Steel Barbecue Mesh CSTAR WIRE MESH ENTERPRISES CO., LTD. ,