① Use a file to remove the burr on the strained part of the valve stem; for the shallower part of the strain, use a flat shovel to process it to a depth of about 1mm, and then use an emery cloth or an angle grinder to roughen it, and a new metal surface will appear at this time .

②Clean the surface with TL-700 metal cleaner to make the repaired surface free of oil, dust and dirt.

③Apply wear-resistant repair agent.

④ detail trimming.

Preparation and coating process of wear-resistant repair agent:

① Prepare the repair agent according to the volume ratio of 3.8:1;

② Apply the adhesive to the scratched surface. The first time should be applied as little as possible, and the adhesive should be applied from top to bottom, and no air bubbles are allowed;

③After 1 hour of the first glue application (that is, after the initial curing of the adhesive), reconcile the repair agent according to the requirements, and carry out the second application, which is required to be 1~2mm higher than the original size;

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

Detailed finishing process requirements:

① Use tools such as files, scrapers and emery cloth to remove the adhesive that is higher than the original size, measure it at any time during operation, do not make the adhesive layer lower than the original size, and reserve 0.5mm as the finishing amount;

②When the size reaches the finishing amount, use the pre-processed grinding tire for trimming (pad with 80-mesh emery cloth);

③When the size is 0.2mm higher than the original size, replace the corundum and grind to the actual size accuracy.

Precautions:

Due to the use of on-site repair, in order to ensure the quality of the repair, the dust and oil around the repair (especially the upper part) must be cleaned; after repair, if there are defects (such as small air holes, etc.), glue must be added, and the operation process is the same as above.