When a valve stem suffers a strain, you can follow the steps below to ensure that the stem is restored to its original function and performance.
I. Preparation Stage
Deburring: First, use a file to gently remove burrs from the stem strain to smooth the surface. For shallow pulls, a flat spatula can be used to a depth of approximately 1mm and sanded with an emery cloth or angle grinder until a new metal surface is exposed.
Cleaning the Surface: Next, use TL-700 Metal Cleaner to thoroughly clean the surface being repaired, making sure there is no oil, dust, dirt or other impurities left behind. This is to ensure that the patching agent can firmly adhere to the metal surface.
Second, applying repair agent
Preparation of Patch: Prepare the wear-resistant patch in the ratio of 3.8:1 by volume. Make sure to measure accurately to obtain the best repair results.
Initial application: Apply the prepared adhesive evenly on the strained surface. Apply the first coat as sparingly as possible, working from the top down to ensure that no air bubbles are created.
Second coat: Wait for the first coat of adhesive to initially cure (after about 1 hour), reconstitute the patch and apply a second coat. When applying this time, the layer of patching agent should be 1~2mm above the original size to ensure that the repaired valve stem has sufficient strength.
Curing treatment: After waiting for the patch to cure naturally for 1 hour, use a tungsten iodine lamp at 80~100℃ to heat the repair area for 3 hours. This will help the patching agent adhere more firmly to the metal surface.
Third, fine repair
Remove excess material: Use tools such as files, scrapers and emery cloths to remove any adhesive higher than the original size. During the operation, measure at any time to ensure that the adhesive layer is not lower than the original size, and reserve 0.5 mm as the amount of fine trimming.
Grinding: When the size reaches the amount of fine finishing, use the pre-prepared grinding tire tool for finishing. Put 80-mesh abrasive cloth on the abrasive tire for preliminary grinding.
Precision Adjustment: When the size is 0.2mm above the original size, replace the emery for grinding until the actual size accuracy is reached. This will ensure that the repaired valve stem has precise size and smooth surface.
IV. Precautions
Clean environment: Since on-site restoration is adopted, please ensure that the environment around the restoration (especially the upper part) is thoroughly cleaned of dust, oil and other impurities. This will help improve the quality of the repair.
Patching: If there are any defects (e.g. small air holes, etc.) after the repair, please carry out the patching process in time. The process of patching is the same as the above steps of applying patching agent.
By following the above steps and precautions, you can successfully repair a strained stem and ensure that it regains its original function and performance.
