Lubrication tips for Swedish SKF bearings

Rust prevention performance

The grease used in SKF bearings must have an anti-rust effect, and the anti-rust agent should preferably be insoluble in water. Grease should have good adhesion to form an oil film on the surface of the steel, even if the grease is filled with water.

Mechanical stability

Grease becomes soft during machining and causes leakage. When there is a vibration application example, grease will be trapped inside the bearing by the bearing housing. If the mechanical stability of the grease is insufficient, the grease will be continuously thrown out of the bearing, which will cause mechanical collapse of the soap structure and destruction of the grease.

Oil seal

Oil seals are necessary to protect bearings and lubricants from external contamination, and no matter whether debris or moisture can penetrate into the bearings to prevent damage. Proper installation and maintenance is an important factor in the longest service life of the bearing. At the same time, attention must be paid to the cleanliness of the bearings, the correctness of the choice of bearings and the selection of appropriate installation and maintenance tools. Bearings must be protected from contaminants and moisture and must be properly installed and lubricated. The design of the bearing arrangement, the condition of the oil seal, the type of lubricant and the lubrication cycle, as well as the special maintenance play an important role.

Mixed grease

Never mix incompatible greases. If two incompatible greases are mixed, the consistency will usually soften and eventually damage may occur due to the loss of grease. If you don't know which type of grease the bearing originally used, you should first remove the old grease inside and outside the bearing to add grease.

Classification of oils and fats

According to temperature and working conditions: grease can be classified according to their allowable working temperature. The consistency and lubricating ability of grease are affected by working temperature. Imported bearings operating at a certain temperature must choose the correct consistency at the same temperature and A grease with good lubrication. Grease is manufactured in different operating temperature ranges and can be classified into low temperature (LT), medium temperature (MT) and high temperature (HT) greases. At the same time, there is a type of grease called EP (extrusion resistant) or EM (resistant to extrusion and added molybdenum disulfide), with additives to enhance the strength of the lubricant film.https://www.supplyforever.com/

45 steel hardness

Commonly used medium carbon quenched and tempered structural steel. The cold plasticity of the steel is generally good. The annealing and normalizing are slightly better than the quenching and tempering. It has high strength and good machinability. After proper heat treatment, certain toughness, plasticity and wear resistance can be obtained. Convenience. Suitable for hydrogen welding and argon arc welding, not suitable for gas welding. Preheating is required before welding, and stress relief annealing should be performed after welding.
Normalizing improves the cutting performance of blanks less than 160 HBS. After the steel is quenched and tempered, its comprehensive mechanical properties should be optimized for other medium carbon structural steels, but the steel has low hardenability, and the critical hardenability diameter in water is 12~17mm, and there is a tendency to crack when water quenching. When the diameter is more than 80mm, the mechanical properties are similar after quenching or tempering, and the medium and small mold parts can be quenched and tempered to obtain higher strength and toughness, while the large parts are treated with normalizing. Therefore, this steel is usually used in quenched or tempered condition.
Quenching and tempering has a range of hardness, generally between 225-297HB. 45# steel is quenched and tempered, that is, quenching + high temperature tempering, the hardness should be at 297HB, that is, 31 ~ 32HRC! This is the most ideal state. This value may not be reached in general.
45 steel quenching, if water quenching can generally reach 40----60HRC (according to water temperature and material size), quenching with oil is generally between 30----55HRC (depending on the thickness of the material and the type of quenching oil) https://www.supplyforever.com/