Rebuilding Of Power Blocks
UPS 320 EG '80' Elastomer (TR320)
The following ThistleBond section is concerned with the rebuilding of power blocks and should be read in conjunction with the Technical Data sheets of the following ThistleBond Products: 80 Durometer Elastomer Paste.
COMMON DEFECTS
Mechanical damage to lining material caused by wear and abrasion.
PREPARATION
All work should be carried out in strict accordance with the relevant ThistleBond Technical Data Sheet. Repairs to the power block can be carried out in situ, but it may be necessary to construct a suitable tented work space in order to protect the power block and working engineer from adverse weather conditions. To obtain optimum results, it will be necessary to pre form a suitably rigid template, shaped to give the desired final contour of the power block.
SURFACE PREPARATION
Thoroughly fry the repair area and cut away all loosely adhered material using a sharp knife. Undercut existing rubber covering at the extremity of the repair area. Roughen the exposed power block carcass using an angular grinder, fitted with a cutting wheel, or a similar tool capable of roughening the surface. The surrounding rubber coating should also be roughened using a roughing brush to produce a woolly surface. If an entire new coating is to be applied, then the metallic carcass of the power block should be roughed by grit blasting to Swedish Standard Sa2½ ensuring a minimum profile of 75 microns, using an angular abrasive.
PRIMING SYSTEM
Apply the ThistleBond Primer supplied with the 80 Durometer Elastomer product in a thin film using a stiff bristled brush to the entire prepared area. All surfaces to which the material is to bond to must be treated.
APPLICATION TECHNIQUE
Mix the selected ThistleBond product in accordance with the Technical Data Sheet. Using a short Bristled Brush or the flexible applicator provided, apply a thin layer of product to wet out the prepared surface. Ensure that this material is pushed well into the prepared profile. Using a suitably shaped rigid template, apply further product whilst the power block is slowly rotating, until the original profile has been restored.
TECHNICAL SUMMARY
PRODUCT ABRASION WORKING FULL CURE
RESISTANCE LIFE (20°C) (20°C)
80 DUROMETER
ELASTOMER PASTE EXCELLENT 15 MINUTES 72 HOURS