Creating Irregular Shims
Common Defects
Incorrect lead transition due to misalignment or distortion of mating faces. Damage caused by abrasion due to differential movement between mating faces.
Preparation
All work should be carried out in strict accordance with the relevant ThistleBond Technical Data Sheet. The product selection and application techniques should be based on the nature of the equipment, the environment and the time available to carry out the work. Specific consideration should be given to achieving correct leveling and alignment of the equipment.
Surface Preparation
All mating surfaces should be washed with UPS TAC 883 Universal Cleaner in order to remove all dirt and grease, loose paint flakes and scale. The irregular shim maybe bonded to either face and therefore should be Grit Blasted using an angular abrasive to give a surface finish of Swedish Std Sa2½ ensuring a profile of 75 microns minimum. Any surfaces to which the material should not be bonded must be treated with UPS TAC 872 Release Agent. Alignment and leveling of the equipment should be achieved using either jacking bolts or shims. Wherever possible a minimum clearance between mating faces of 1/16” should be achieved.
Application Technique
The edges of the mating faces should be sealed using (please use appropriate product depending on enviroment) UPS 105 EG Metal Repair Paste (TR1025, UPS 115 XL Extended Life Metal Repair (TR115), UPS 200 EG Ceramic Repair Paste (TR200) or UPS 230 EG Urethane Ceramic Paste (TR230). Injection holes should be carefully positioned, together with the vent holes to prevent the formation of air traps. Ideally injection points should be spaced no more than 24” apart. The selected material should be loaded into disposable injection cartridges and injected using pneumatic equipment. The application should progress along until it is exuded from the next injection point. When the first hole should be sealed with a suitable bung and injection commenced at the next hole. Continue until all the voids have been filled. The product should then be left undisturbed to fully cure before the equipment is returned to service. Where equipment can be readily maneuvered and realigned, a paste grade ThistleBond material may be used (use one of the above). This should be applied to both mating surfaces ensuring that an excess of product is applied and that it is in a peak towards the centre, so that when the faces are brought together the product is exuded out, preventing any air entrapment. Check that the equipment is accurately located. Any material exuded out should then be removed and the product allowed to cure before returning to service.
Recommended Equipment
Mixing and application tools are included in each pack of ThistleBond Product. Prior to carrying out the repair however, it is important that all necessary tools and equipment are available on site. These could include the following – Grit Blasting equipment, UPS TAC 883 Universal Cleaner, UPS TAC 872 Release Agent, Protective Clothing, Polyethylene Tenting.