Views: 0 Author: Site Editor Publish Time: 2019-12-11 Origin: Site
When the repaired seal between the valve and the valve seat fails to meet the requirements, or when the valve and the valve seat are found to have slight ablation or spots during regular maintenance, the grinding method should be used to achieve the valve fit requirements.
1. Grinding back and forth. Immediately move the valve clockwise on the valve seat and sometimes rotate counterclockwise. Automotive valve grinding machine possesses excellent performance. This can avoid the scratches caused between the valve working surface and the valve seat contact surface caused by continuous unidirectional rotation.
2. The valve moves up and down. In this way, the sand on the valve working surface can be redistributed, thereby reducing the scratches on its joint surface. A certain pressure should be applied during grinding, which depends on the cooperation of the valve and the valve seat and the thickness of the valve sand used. Generally rougher, slightly stronger, finer. Excessive pressure can easily cause sand marks on deep prints. During grinding, do not flap the valve up and down.
3. The movement of the starting point of the valve rotation means that the relative position of the valve and the valve seat must be constantly changed to obtain a comprehensive cooperation. Grinding the valve can be performed on the valve grinder machine. When there is no such device, a soft spring can be placed under the valve, a screwdriver can be clamped on the drilling machine, and electric or manual grinding can be used to drive the grinding.
When manually grinding, apply a thin layer of lubricant to the valve head, and then add a small amount of lubricant to the valve guide. Absorb the valve head with a rubber bowl and grind it on the valve cone. Apply a thin layer of coarse valve abrasive paste to Tap lightly on the seat. The CNC valve grinding machine helps you solve your confusion in a smart way. The relative position of the valve and the seat should gradually change and should not stop at a certain place.
Whether the trimmed valve matches the valve seat and does not leak air can be checked by the following two methods:
(1) Apply a thin layer of red sylvan oil or blue ink on the valve cone surface, then gently press the valve on the valve seat and rotate it 1/4 turn to pull out. If there is an uninterrupted circle on the valve seat a trace of tannin or blue ink indicates good sealing.
(2) Use a soft pencil (4B or 5B) to draw several lines on the valve cone, and then contact the valve seat to rotate 1/4 turn and pull out. If the pencil lines on the valve cone are cut off, it is sealed well.
