Customized Roller Bearing

Characteristics and causes of bearing grinding cracksGrinding is a common metal cutting process in the machinery manufacturing industry and is also widely used in the bearing processing industry. During the grinding process, heat-treated and quenched bearing parts may develop a network of cracks or regularly arranged fine cracks, known as grinding cracks. These cracks not only affect the appearance of bearing parts but, more importantly, directly impact their quality. This article discusses the characteristics and causes of bearing grinding cracks, as well as preventative measures.

The hidden truth behind the "abnormal sonata" of bearings1. Lubrication factorsLubrication is as important to bearings as blood is to the human body. When lubrication is insufficient, an effective lubrication film cannot be formed at key friction points such as between the rolling element and raceway, between the cage and the rolling element inside the bearing, and the metal surfaces are in direct contact, causing the friction coefficient to increase dramatically. This dry friction between metals will generate a lot of heat, accompanied by a sharp "squeaking" sound, like the sound of scratching a blackboard with fingernails, which is very irritating. For example, in some high-temperature, high-speed mechanical equipment, if the grease is not replenished in time, the lubrication state of the bearing will deteriorate rapidly, and abnormal rotation noise will also appear.2) Installation problemsInstallation is a key link to ensure the normal operation of the bearing. Any slight improper installation may become a hidden danger of abnormal rotation noise. Installation eccentricity is a common problem. When the bearing is not accurately aligned with the shaft or bearing seat during installation, the force inside the bearing will become uneven. Some rolling elements are under pressure, while other parts are underloaded. This uneven force state will cause the movement trajectory of the rolling elements on the raceway to deviate, generate additional friction and vibration, and emit an abnormal "clicking" sound.3) Quality defectsThe quality problem of the bearing itself is also an important reason for abnormal rotation noise. Material defects are a manifestation of quality defects. For example, during the production process of the rolling element or ring of the bearing, if there are defects such as pores, sand holes, inclusions, etc. inside the material, these defective parts are prone to stress concentration when bearing loads, resulting in a decrease in the strength of the local material. As the bearing runs, these weak parts will gradually develop cracks, peeling and other damages, resulting in abnormal rotation noise. In order to reduce costs, some small manufacturers do not strictly control the purchase of raw materials and use poor quality steel, and the bearings produced are prone to such problems.4) Overload operationBearings are designed with a rated load capacity. When the equipment is in an overloaded state for a long time, the actual load on the bearing far exceeds its rated load. This will cause excessive pressure on the parts inside the bearing, resulting in a sharp increase in the contact stress between the rolling element and the raceway, and increased surface wear. As wear continues to develop, the clearance of the bearing will gradually increase, the stability of the internal structure will be destroyed, and abnormal rotation noise will be generated. On the production lines of some factories, in order to pursue output, the equipment is in a high-load operation state for a long time. The bearing is subjected to excessive pressure for a long time, and abnormal noise will soon appear, shortening the service life of the equipment.

Choice between bearing grades P4 and P5: Which is better?When choosing a bearing grade, there are significant differences between P4 and P5 bearings in terms of dimensional precision, rotational precision, and surface quality.The dimensional precision and rotational precision of P4 bearings meet ISO tolerance grade 4. Compared with P5 bearings, P4 has stricter requirements in terms of dimensional requirements, rotational accuracy, surface shape, and surface quality.Specifically, P4 bearings have smaller dimensional deviations (such as inner diameter, outer diameter, ellipse, etc.), stricter rotational accuracy (such as inner radial runout, outer radial runout, end face to raceway runout, etc.), and stricter requirements in terms of surface roughness, circular deviation, groove deviation, etc. Therefore, if higher precision and performance are required, P5 bearings are a better choice.

Small bearings, big power: Uncovering the fascinating world of thrust ball bearingsThe secret of structure: Understanding the composition of thrust ball bearings(I) Three core componentsThrust ball bearings are mainly composed of three core components: shaft ring, seat ring and steel ball cage assembly. They are like a small team that works together tacitly, each playing a unique role to jointly ensure the efficient operation of the bearing.The shaft ring, as a component that closely cooperates with the shaft, is like a rider and a horse. The shaft ring closely follows the rotation of the shaft and accurately transmits the rotational motion of the shaft.When the motor's rotor rotates at high speed, the shaft ring is firmly mounted on the shaft and dances synchronously with the shaft to ensure the stability of power transmission. The seat ring cooperates with the housing, like a solid fortress, to provide reliable support for the entire bearing system. In the elevator's traction machine, the seat ring is firmly fixed on the machine base, bearing the huge axial pressure from the car and counterweight, so that the shaft ring and steel ball cage assembly can operate safely on it.The ball cage assembly is a smart dancer in the bearing. The steel balls roll happily in the raceway grooves, taking on the important task of reducing friction and transmitting loads. The cage is like a responsible leader, cleverly separating the steel balls evenly to prevent them from colliding with each other, ensuring that the steel balls can maintain a stable formation even when rotating at high speeds, and transmitting axial forces in an orderly manner.