What are the precautions for the lubrication and maintenance of the bearings of the ball mill?
Answer: Whether in cement production, mineral processing or coal mine processing, it is very necessary to do a good job in the protection of the ball mill production equipment. Especially before the start of actual production and during the production process, doing a good job in the lubrication and maintenance of the main bearing of the ball mill is quite important. For... The quality of brake fluid directly affects the braking performance of a car, relates to the safety of the car and the safety of human life and property. When selecting brake fluid, you can judge the quality of the brake fluid from the following several standards! 1. Impact on rubber. The bowl and gasket in the brake pump of the braking system are made of rubber parts. Their materials include EPDM, styrene-butadiene rubber, etc. Qualified brake fluid has good adaptability to rubber and will not cause rubber contraction. Compressed rubber bowls have a reduced root diameter, making it easy for brake fluid to leak out, causing brake failure. 2. pH value. Materials that come into contact with brake fluid include metals, rubbers, plastics, etc. To avoid corrosion or rusting of these materials by brake fluid, the pH value of the brake fluid in use should be greater than 7 and less than 11.5. The pH value is an important indicator of whether the brake fluid is acidic or alkaline. If the pH value 11.5, it is strongly alkaline, which also corrodes relevant components of the braking system. Good brake fluid has a pH value between 8.0 and 9.5 to ensure that active aluminum and other metal components are not corroded. 3. Dry and wet balanced reflux boiling point. The dry and wet balanced reflux boiling points of automotive brake fluid are important indicators to ensure effective braking. Due to frequent braking while driving, heat generated by the friction of the brake shoe causes the temperature of the brake fluid to rise. When low-boiling substances or small amounts of water are present in the brake fluid, gas bubbles or gases are easily produced. In this case, when stepping on the brake pedal, there will be a feeling of missing a step or feeling that the brakes are not working properly. Therefore, the national standard GB12981-2003 stipulates that the dry boiling point of brake fluid must be greater than 205℃ and the wet boiling point must be greater than 140℃. 4. High and low temperature kinematic viscosity. Good brake fluid can ensure reliable braking not only in high-temperature areas (above 30℃) but also in cold areas (below -30℃). According to the national standard GB12981-2003, the kinematic viscosity at 100℃ must be greater than 1.5mm2/s, and the kinematic viscosity at -40℃: HZY-3, HZY-4 grade must be less than 1500mm2/s; HZY-5 grade must be less than 900mm2/s. Brake fluid that meets national standards ensures that the brakes don't feel soft in high temperatures and don't lag in low temperatures. 5. Metal corrosion. Metals that come into contact with automotive brake fluid include iron, copper, aluminum, and alloys. Once these metals are corroded, the brake fluid is prone to leakage or causes rusting of the metal parts of the braking system, or leads to jamming situations, resulting in brake failure. Therefore, qualified brake fluids all contain corrosion inhibitors, antioxidants, and other additives. The national standard GB12981-2003 specifies the metal corrosion test index as: cast iron mass change ±0.2mg/cm2, aluminum mass change ±0.1mg/cm2 (100℃/120h). How to select? 1. Look at the price. Based on the current cost of brake fluid materials, assuming each bucket contains 1 kilogram of brake fluid, if the price is less than 10 yuan per bucket, it is difficult to confirm it as qualified brake fluid. 2. Look at the color. Good brake fluid is light yellow, transparent, and free of impurities. After opening the bottle, there is no strange smell. Unqualified brake fluid has a foul odor, is not transparent, is colorless or has strange colors. 3. Look at the packaging. According to the national standard GB12981-2003, the balance reflux boiling point and wet balance reflux boiling point must be indicated on the outer packaging of the brake fluid. Carefully check whether there is a production license number. Do not purchase brake fluid that does not indicate these three items on the packaging bucket. Do not select brake fluid without an XK18-001-00XXX license number on the outer packaging. Without a manufacturer, no production date, no sales service telephone number, or if the phone cannot be reached, it is not advisable to select such products. The above content is jointly released by the Sanitation Garbage Truck Official Website (http://www.clwlu.com/)|www_clwlu_com and Garbage Truck Manufacturer (http://www.clwwcw.com/)|www_clwwcw_com, for more wonderful content: