Reliable in extreme heat and dirt: linear guides for dental casting units

• What was needed: linear guide for the opening and closing mechanism of the pressure vessel
• Requirements: A durable and reliable product was needed that could withstand high temperatures and a high volume of dirt in the application.
• Industry: Medical technology
• Success for the customer: The drylin® W-linear guides used are 100% lubrication-free so that the bearing points do not become clogged with dirt. The loss of function and maintenance costs associated with potential clogging are therefore eliminated. The bearings run quietly and work perfectly in dirty, damp and high ambient temperatures.

The Heracast EC inductive casting unit is a laboratory unit for casting all precious metal and almost all non-precious metal and model casting dental alloys for dental applications with a liquidus point from 500 °C to over 1600 °C.

To minimize the risk of injury, the moving components of this casting unit have been moved to the interior, where a vacuum prevails. A durable and reliable mechanism was required to open and close the pressurized chamber in which the vacuum is created; however, the special nature of the application posed various challenges. For example, the tooth alloys that are cast in the device are extremely hot, so the mechanism must be able to permanently withstand high temperatures. There is also a high risk of contamination in the application.

The customer was looking for a solution that would permanently reduce the maintenance effort in order to make handling the device as easy as possible.

The design engineers at Heraeus Kulzer opted for drylin® W linear rails and linear housings. The linear system significantly minimizes wear on the safety-relevant closure system when opening and closing the vacuum pressure vessel. In addition, this system has enabled the rotational movement of the entire chamber to be decoupled and shifted to the interior, minimizing the risk of injury.

Unlike conventional linear guides with recirculating ball bearings, drylin® linear bearings glide on tribologically optimized sliding foils.

Thanks to the solid lubricants integrated into the plastic , there is no need for no external lubricants that could become clogged with dust and dirt. This improves the service life and reduces the need for maintenance. The linear bearings also run particularly quietly and have high wear resistance. They are unaffected by moisture and high ambient temperatures.