Slewing bearing housings are large and extra-large bearing housings with special structures capable of withstanding comprehensive loads. They are characterized by their compact structure, flexible rotation, and convenient installation and maintenance. Where there is a bearing, there must be a support point. The internal support point of the bearing is the shaft, and the external support is what is commonly referred to as the bearing housing.
Protection and maintenance of bearing housings:
(1) Application of bearing housing cooling system. When used correctly, bearing housing cooling water not only extends the service life of the bearing housing, but also improves production efficiency. The material of bearing housing is generally a special bearing housing steel manufactured through various processes. Even the best bearing housing steel has its limits, such as temperature.
If the mold temperature is too high during use, the bearing housing is prone to developing cracks on the mold core surface prematurely. Some bearing housings even show large-area cracks before exceeding 2000 molding cycles. In some cases, the mold core even changes color due to excessively high bearing housing temperatures during production, reaching over 400 degrees Celsius. Such temperatures, combined with the rapid cooling effect of the release agent, easily lead to cracking, and the produced products are prone to deformation, tearing, and sticking to the mold.
Using cooling water in the bearing housing significantly reduces the need for release agents, eliminating the need for operators to use them to lower the bearing housing temperature. This benefits include extending bearing housing life, shortening die-casting cycles, improving product quality, reducing sticking, scratches, and aluminum adhesion, and minimizing release agent usage. It also reduces wear on ejector pins and cores caused by overheating of the bearing housing.
(2) It is necessary to preheat the bearing housing during the initial production process to prevent cracks from appearing when the cold bearing housing suddenly encounters hot molten metal. For more complex bearing housings, a blowtorch or liquefied gas can be used, and a mold temperature controller can be used if conditions are good. For simpler bearing housings, slow injection preheating can be used.
(3) Cleaning the parting surface of the bearing housing is a very time-consuming and easily overlooked task. The operator should use kerosene to thoroughly clean the parting surface of the bearing housing. This will not only prevent the bearing housing from being damaged by squeezing, but also clear the venting grooves on the bearing housing that are blocked by the residue of the release agent or other dirt. This will help to release the gas in the cavity during the injection process and improve product quality.
(4) If the bearing housing is equipped with neutron control, be sure to absolutely prevent any joints in the signal line between the die-casting machine and the bearing housing. The reason is clear: in daily production, it is difficult to prevent water from getting on the signal line, or the joint may be easily broken, resulting in a short circuit with the machine tool. If a signal error occurs, at best it will cause an alarm and automatic shutdown, delaying the machine; at worst it will cause signal disorder, damaging the bearing housing and resulting in unnecessary losses.
