A grinding wheel is an abrasive tool with certain hardness and strength, which is usually round and has a round hole in the middle. Grinding wheel is mainly made of abrasives, pores and binders.
In recent years, we often see news about the fractures and injury of grinding wheel in use. Many enterprises will put the responsibility of grinding wheel fractures on the grinding wheel manufacturer. In fact, the reasons for the fractures of the grinding wheel are quality problems, but also related to storage, transportation and the use method of the grinding wheel. Here, we will explain in details the reason why the grinding wheel is broken.
Ⅰ. Grinding Wheel Quality and Inspection
1. Grinding Wheel Quality
To ensure the quality of grinding wheel production, we must use high-quality raw materials, binders and advanced production technology. At the same time, we should also pay attention to the production process and the quality of workers. Only when various problems are paid attention to can we produce high-quality grinding wheels.
2. Grinding Wheel Inspection
After the finished grinding wheel is discharged from the furnace, it shall be subject to balance detection, acoustic inspection for cracks, rotation test, etc., so as to ensure that the grinding wheel meets the requirements of the workpiece in use.
Ⅱ. Grinding Wheel Storage and Transportation
1. Grinding Wheel Storage
The grinding wheel shall not be stored in places easily affected by moisture, freezing and high temperature. The rubber grinding wheel shall avoid contact with oil. The resin grinding wheel shall be suitable for one year. The grinding wheel beyond the storage life shall be strictly inspected and confirmed to be free of problems before use.
2. Grinding Wheel Transportation
- The grinding wheel must be completely packaged and transported to avoid collision. It shall not be exposed to moisture for a long time and shall not be in contact with alkali;
- The grinding wheels shall be stacked neatly in a flat way, and shall not be placed obliquely and under pressure for a long time to prevent deformation;
- Avoid direct contact with the ground. It must be stacked on the ground with moisture-proof wooden pallets, 10-15cm above the ground, and the stacking height shall not exceed 1m;
- The product can only be used after it has been used for more than one year and its turning strength and appearance should be re tested.
Ⅲ. Use of Grinding Wheel
In terms of the use of grinding wheel, different grinding machines will have many different characteristics according to different industries, different processing methods and different grinding machines.
According to different uses, grinding methods and types of grinding machines, grinding wheels are made into various shapes and sizes. The commonly used grinding wheels include flat grinding wheels, cylindrical grinding wheels, double bevel grinding wheels, cup grinding wheels, bowl grinding wheels, dish grinding wheels, etc.
Causes & Solutions of Grinding Wheel Fractures
1. Fractures Caused By Crack of Grinding Wheel
- Problem ①: the grinding wheel is installed violently
Solution: the grinding wheel hole and shaft should be installed smoothly rather than rigidly.
- Problem ②: use flange only on one side
Solution: the size of the grinding wheel flange should be exactly the same on both sides and fastened evenly.
- Problem ③: uneven support of flange
Solution: the left and right sides of the grinding wheel flange shall be processed into correct and smooth dimensions, and the plane of the lead filling layer shall not protrude.
- Problem ④: flanges sizes on both side are different
Solution: the left and right flanges must be of the same size.
- Problem ⑤: the gasket is not used or the diameter of the gasket is too small or too thin
Solution: use gaskets with high strength and large diameter.
- Problem ⑥: there is no groove on the inner side of the flange or its diameter is small
Solution: the inner side of the flange must be provided with a groove of the specified size.
- Problem ⑦: the tightening force of the nut is too large
Solution: the excessive force of the fastening nut of the flange will skew the flange and increase the local force of the grinding wheel, so it should be tightened appropriately.
- Problem ⑧: only grinding power is considered
Solution: because the strength of grinding wheel with coarse grain size or low hardness is particularly small, attention should be paid to grinding.
2. Excessive linear Speed of Grinding Wheel
- Problem ①: the rotation speed of the grinding wheel shaft is too high and the diameter of the grinding wheel is large
Solution: change the rotation speed of grinding wheel shaft or use grinding wheel with small diameter.
3. Workpiece is Stuck Between Frame and Grinding Wheel
- Problem ①: poor alignment of workpiece support
Solution: the interval between the workpiece support and the grinding wheel working surface shall be less than 3mm.
- Problem ②: when side grinding is carried out without a workpiece frame for side grinding
Solution: flat grinding wheel is forbidden to be used for side grinding. Bowl grinding wheel shall be used for side grinding, and the workpiece support shall be set up correctly.
4. Inadequate Inspection of Grinding Machine or Improper Machine Tool
- Problem ①: the bearing is loose, the spindle is bent, and the accuracy of the grinder is significantly reduced
Solution: check and repair the grinder to improve its accuracy.
- Problem ②: the shaft diameter of the grinding wheel shaft is too small
Solution: try to use the grinding wheel with the same aperture as the shaft.
- Problem ③: rough grinding or wrong use of grinding wheel
Solution: carry out correct grinding operation by relying on professional guidance or grinding wheel operation manual.
5. The Unbalance of Grinding Wheel is Too large
- Problem ①: insufficient balance check of grinding wheel manufacturer
Solution: re calibrate on the balance frame.
- Problem ②: the grinding wheel contains some water
Solution: make the grinding surface idle when the water injection is stopped.
6. Side Grinding with Unsuitable Grinding Wheel
There are strict regulations on the use surface of the grinding wheel, and it is strictly prohibited to use the grinding wheel for side grinding at will.