Repair method for valve stem scratches

What to do if the valve stem is scratched?

    ①Use a file remove the burrs from the scratched part of the valve stem; for areas with shallow scratches, use a flat chisel to process to a depth of about 1mm and then use sandpaper or an angle grinder to rough it up, at which point a new metal surface will appear.

    ②Clean the surface with TL-70 metal cleaner to ensure that the repaired surface is free of oil, dust, and other contaminants.

    ③Apply wear-resistant repair compound.

    Fine detail adjustment.

    Mixing and application process for wear-resistant repair compound:

    ①Mix the repair compound in a volume ratio of 3.:1;

    ②Scrape the adhesive onto the scratched surface, applying as little as possible for the first time, from top to bottom, and ensuring no air are present;

    ③After 1 hour of the first coating (i.e., when the adhesive has initially cured), remix the repair compound as required and a second coating, which should be 1~2mm higher than the original size;

    ④After natural curing for 1 hour, heat with an iod tungsten lamp at 80~100℃ for 3 hours.

    Fine detail adjustment process requirements:

     ①Use tools such as, scrapers, and sandpaper to remove the adhesive that is higher than the original size. Measure frequently during operation to ensure that the adhesive layer does not go below the original size and leave a margin of 0.5mm for fine adjustment;

    ②When the size reaches the fine adjustment amount, use the pre-processed grinding fixture for adjustmentwith 80-grit sandpaper on top);

    ③When the size is 0.2mm higher than the original size, change the diamond sand and until the actual size precision is achieved.

    Precautions:

    Since on-site repair is used, in order to ensure the quality of the repair, the, oil stains, etc. around the repair (especially the upper part) must be cleaned up; if there are defects (such as small air holes, etc.) after the, additional adhesive should be applied, and the operation process is the same as above.