Development of Impregnation Technology

Recycling Sealant

Development of Impregnation Technology

Recycling Sealant

Recycling sealant machine
Sealant recycling process plant
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During the 10 year development programme in Guernsey, the Vertical Transfer System (VTS) Patents: UK Feb 1984. No: 8402770. USA Feb 1988. No: 4,620,991, was introduced into normal batch processing equipment, followed by rotational cascade washing and curing. The first of such machines was installed in a new job shop at Ultraseal’s factory at Coleshill. This development was significant in the build up to producing the first process plant for recycling sealant.

During traditional impregnation practice almost all the sealant used in the impregnation cycle went down the drain as effluent. This wasn’t so with recycle technology, making it a major landmark of achievement. Statistically, barely 0.5% of sealant is absorbed in even the most porous component, except sintered parts.

At one stage in sealant development, the Guernsey laboratory embarked on developing new and interesting monomers by esterification and trans-esterification reaction. It was through this work that it was realised that recycling of sealant was a real possibility. The research laboratory was well equipped and produced 10 years of valuable information to further develop the impregnation process.

Front Load Processing

Front load impregnation plant
Front load impregnation plant
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In the mid 80’s, the next major step in Ultraseal’s development programme was the introduction of ‘Front-load’ processing which added an important touch to impregnation process application. One important feature was to allow rotation during the impregnation cycle. Until this point in time, the process was carried out in the impregnation chamber with the components held in a stationary position. This process was fine if the position of the porosity was known and allowed for, but in the majority of cases it was not known and subsequently air locking in the vicinity of the porosity could inhibit the sealing process. Little was understood about this phenomenon although correct positioning of the component was found to play an important part in impregnation efficiency. With the advent of Front Load Technology it became possible to rotate about a horizontal axis. This released any air locking at a critical part of the process and allowed the sealant unimpeded access to penetrate the porosity.

Today Front Load Technology (FLT) is having an increasing impact on production line impregnation processing, because it can be installed in the manufacturing facility. No longer is it necessary to move components to a remote impregnation machine, risking damage and loss of identity, and increasing the cost of work in progress. FLT continues to be developed with the aim of completing the full cycle of impregnation in one chamber.

With the possibility of using fast cycles it is conceivable that a bank of several modules could satisfy the needs of a high volume production environment, whilst providing the confidence that even if one machine went down, production could at least continue at a lower level until repairs were made.