Grinding machine is one of the most commonly used machines and equipment in machinery factory. Is its installation reasonable and meets the safety requirements? Whether its use method is correct and whether it conforms to the safety operation regulations. These problems are directly related to the personal safety of every employee, so we must pay enough attention to them in practical use. When installing, the safety and quality of grinding wheel should be tested first. Method: Tap the side of the grinding wheel with a nylon hammer (or pen), and the sound will be clear.
The positioning problem of where the grinder is installed is the first problem we should consider in the installation process. Only when a reasonable and suitable post is selected can other work be carried out. It is forbidden to install the grinder in a place facing nearby equipment and operators or where people often pass by. Generally, a special grinding wheel room should be set up in a larger workshop. If it is really impossible to set up a special grinding wheel room due to the terrain limitation of the workshop, a protective baffle with a height not less than 1.8m should be installed on the front of the grinder, and the baffle should be firm and effective.
Balance problem The imbalance of the grinding wheel is mainly due to the inaccurate manufacture and installation of the grinding wheel, which makes the center of gravity of the grinding wheel not coincide with the rotating shaft. The harm caused by imbalance is mainly manifested in two aspects. On the one hand, when the grinding wheel rotates at high speed, it causes vibration, which is easy to cause polygonal vibration marks on the surface of the workpiece; On the other hand, unbalance accelerates the vibration of the spindle and the wear of the bearing, which will cause the grinding wheel to break and even cause an accident. Therefore, it is required that the sand office building with a height greater than or equal to 200mm should be statically balanced after the chuck is installed, and the grinding wheel should be repeatedly statically balanced after dressing or finding imbalance during work.
Matching problem Matching problem mainly refers to the installation matching problem of chuck and grinding wheel. According to the standard requirements, the diameter of the grinding wheel chuck shall not be less than 1/3 of the diameter of the installed sand table, and it is stipulated that when the diameter of the grinding wheel is larger than the diameter of the chuck 10mm, a new grinding wheel shall be replaced. In this way, there is a matching problem between chuck and grinding wheel, otherwise such a situation will occur, and "big horse-drawn cart" will cause waste of equipment and materials; The "small horse-drawn cart" does not meet the safety requirements and is easy to cause personal accidents. Therefore, the reasonable matching of chuck and grinding wheel can save equipment and cut materials on the one hand; On the other hand, it meets the requirements of safe operation. In addition, a buffer pad with a diameter 2mm larger than that of the chuck and a thickness of 1mm~2mm should be installed between the grinding wheel and the chuck.
The protective cover is the most important protective device of the grinder, and its function is to effectively cover the grinding wheel fragments when the grinding wheel is damaged for some reason during work, so as to ensure the safety of personnel. The grinding wheel guard plate has two shapes: round and square, and the maximum opening angle is not allowed to exceed 90; The protective cover is made of steel with tensile strength not less than 4 15N/mm2. When replacing a new grinding wheel, the protective cover shall be installed firmly and reliably, and shall not be disassembled or discarded at will.
The baffle is one of the main protective accessories of the grinder. When the opening of the protective cover is greater than or equal to 30 (higher than the horizontal plane of the spindle), this device must be set. Its main function is to shield the flying noise during grinding, so as not to hurt the operator. Installed at the positive end of the protective cover opening, its width should be greater than the width of the grinding wheel protective cover, and firmly fixed on the protective cover. In addition, the clearance between the circumferential surface of the grinding wheel and the baffle is required to be less than 6mm.
Support problem Support is one of the commonly used parts of grinder. According to the regulations, grinding machines with grinding wheel diameter above 150mm must be equipped with adjustable supports. The distance between the grinding wheel and the bracket should be less than 1/2 of the minimum size of the workpiece to be ground, but the maximum distance should not exceed 3mm.
Grounding problem grinder uses power cord, so the equipment shell must have good grounding protection device. This is also one of the important factors that are easy to cause accidents. Side grinding problem:
In the daily use of grinder, we can often find that some operators grind the side of grinding wheel at will, regardless of the type of grinder or grinding wheel, which is a serious violation of safety operation regulations. According to the regulations, grinding wheels with circumferential surface as working surface are not suitable for side grinding. This kind of grinding wheel has great radial strength and little axial strength. When the operator exerts too much force, the grinding wheel will break and even hurt people. This kind of behavior should be prohibited in the actual use process.
Positive operational problems:
In daily use, many operators are always used to operating grinding wheels because they can work hard in this direction. In fact, this behavior should be explicitly prohibited in the operation of grinding machines. According to the operating rules, when grinding a workpiece with a grinder, the operator should stand on the side of the grinding wheel, not on the front of the grinding wheel, so as to avoid the grinding wheel flying out or the grinding wheel fragments flying out when the grinding wheel fails to hurt people.
Difficult operation problem:
When using the grinder, some operators, especially young operators, use too much force to grind quickly, which is an extremely unsafe operation behavior. The flat body of any grinding wheel has a certain strength, which is likely to cause the grinding wheel to break or even fly out to hurt people. It is also a prohibited act.
* * * Same operational problem:
In the actual daily operation, there are also some people who use a grinder to operate at the same time in order to catch up with production tasks and working hours. This is a serious illegal operation and should be strictly prohibited. When a grinder is not enough, you can add a grinder to solve it. It is absolutely not allowed to use the grinder at the same time. Wear problem:
Any grinding wheel has certain wear requirements. If the wear reaches a certain level, a new grinding wheel must be replaced. You can't use it just to save materials. This is a very unsafe violation. Generally speaking, when the grinding wheel is worn to a diameter larger than the chuck diameter 10mm, it should be replaced with a new grinding wheel.
Validity period:
The new grinding wheels brought out from the warehouse are not necessarily qualified grinding wheels, and even the new grinding wheels bought from manufacturers are not necessarily qualified grinding wheels. Any grinding wheel has a certain period of validity, and qualified grinding wheels are used during the period of validity; If it is used beyond the validity period, it may not be a qualified grinding wheel. The regulation stipulates that "grinding wheels should be used within the validity period, and resin and rubber bonded grinding wheels must pass the rotation test after being stored for one year, and qualified grinding wheels can be used".
Texture problem:
In the process of use, if cracks are found in some parts of the grinding wheel, it should be stopped immediately and replaced with a new grinding wheel to avoid damage to the grinding wheel. Environmental issues:
In general, the grinder should be equipped with a special grinding wheel room. It is forbidden to pile flammable and explosive articles in the grinding wheel room or near the grinder to avoid fire or explosion accidents, and other parts or articles should not be placed around the grinder.
Management issues:
There should be a special person in charge of the grinder. Any non-unit personnel who want to grind objects on the grinder must obtain the permission of the full-time person in charge and strictly abide by the safety operation rules. Without the consent of the person in charge, it is strictly forbidden for outsiders to use the grinder. In addition, a special person should be responsible for replacing the grinding wheel, and it is strictly forbidden for others to replace or install the grinding wheel without permission.
Car shutdown problem:
After the operator stops working, he should turn off the car immediately. It is strictly forbidden for the grinder to be idle or unattended. In addition, short-wave and medium-wave turbines should be kept clean after use.