General | 23. July 2021 Maintenance the easy way with DIAMANT moglice

In our extensive product portfolio, the sliding lining moglice has a high priority. This polymer, which has proven itself in mechanical engineering for slideways, is now also being used by a very large customer for the repair of printing cylinders.

In addition to the usual can containers, moglice is also available in the user-friendly 2-component ready-to-use cartridge system, which ensures ease of use, eliminates mixing errors and protects the user from contact with the polymer.

In the application described here, the repair store is coating the inside of cylinder tubes of hydraulic cylinders used on core shooters for foundry technology. The cylinder tubes have an inner diameter of around 200 mm and a length of around 600 mm.

In everyday operation, the running surfaces for the piston in the cylinder barrel wear, so that regular maintenance is necessary.

To reduce manufacturing costs, the repair store decided against conventional repair methods and opted for coating with moglice. Conventional repair methods require high-precision, time-consuming and expensive reworking of the worn cylinder barrel.

For coating with the sliding coating moglice, the inner surface of the cylinder is only roughly spindled out and cleaned. For the simple application of moglice, the injection technique with the ready-to-use cartridge was chosen. In this process, the 2-component epoxy sliding coating is automatically mixed correctly in a static mixing helix during squeezing out and pressed into a prepared cavity in the still liquid consistency. The cavity was prepared in such a way that a gap of approximately 2 mm was set between the master piston and the spun-out inner surface of the cylinder barrel by means of a precisely manufactured master piston, which was inserted into the cylinder barrel and sealed. The master piston is coated with a release agent before insertion into the barrel to ensure that the polymer moglice does not adhere to the piston but only to the clean, grease- and oil-free inner surface of the cylinder barrel.

To fill the gap evenly, the sliding coating polymer is injected through 3 prepared holes. The pot life, i.e. the processing time window, of approx. 45 min is more than long enough for the gap between the master cylinder and the cylinder barrel to be completely filled. The injected polymer is cured after 24 hours, so that the master piston can be pressed out, i.e. demolded, with a hydraulic press.

Since the surface of the master piston is now mirror-image molded with high precision, no reworking of the surface is required. The cured moglice sliding lining system can be machined conventionally, so that necessary grooves for a lubrication system can be easily inserted.

For the repairer, the clear cost advantage of using moglice is a significant factor in the satisfaction of the end customer and his long-term loyalty to the company.