Project background:
Bearing cage is important part of the use of it directly affects the bearing abnormalities, use of equipment will directly affect the service life of equipment.
Before the test questions:
1, the detection speed slow, unable to realize on-line detection;
2, artificial detection of subjectivity, personnel fatigue;
3, quality management difficult SKF Bearings Construction http://www.skf-ball-bearings.com/derby-bearings-uk.php.htm .
Second, the solution:
1, drect detection, will be deemed to be unqualified in advance;
Part 2, highlight the coaxial light to detect the image, through visual and geometric analysis tools.
3, equipment function and features: est content: cage abnormalities
2, precision: 0.01 mm
3, speed: 0.2 SEC/only
4, advantages: software automatic positioning system guarantee test point always mobile products in the area of image, so as to realize high repeatability, high measurement precision. Direct online detection and improves the production efficiency.
Bearing steel steel billet center segregation of overheat, drawing speed, electromagnetic stirring and temperature of the secondary cooling zone and the conditions of continuous casting machine equipment and other factors. Therefore, the prevention measures:
1. Steel overheating control in the middle
Molten steel overheating determine the immanent quality of continuous casting square billet continuous casting and the macrostructure of the billets, when the interior of the macroscopic crack defects such as steel, drain and shrinkage cavity appear, can be achieved by large compression ratio of the rolling process to improve and eliminate. So hot appear on the high side, the production is not stable, should be small steel continuous casting and rolling specification can solve this problem.
Bearing steel casting process, on the premise of guarantee the steel casting, should use the low superheat casting, usually in 10-20 ℃ overheating control of bearing steel.
2. Control of carbon, phosphorus, sulphur
Carbon, phosphorus, sulphur, three elements segregation coefficient is higher. Sulfur in steel on the high side, can increase the brittleness of steel especially, cause the center segregation and inner crack plate, greatly reduce the sulfur content, reduce the hot brittleness, steel also helps reduce defects such as center segregation and inner crack.
3. Secondary cooling control
Bearing steel crack sensitivity is strong, if increase the intensity of the secondary cooling zone, and increase the gradient of temperature in the plate section, to improve central segregation and cracking tendency. Therefore, use weak secondary cooling water distribution process, and ensure that the secondary cooling water distribution uniformity, can achieve the purpose of reduce the central segregation and fracture.