We know that the operating conditions of the engine valve seat are extremely harsh. In addition to the effects of abrasive wear and impact load, the exhaust valve is also subject to wear and deformation due to corrosion and ablation of high-temperature combustion gases, when such wear and deformation exceeds When the value is certain, it will seriously affect the engine work function. At this time, it is necessary to maintain and maintain the valve arrangement, and restore the excellent sealing of the valve and the valve seat to restore the excellent technical condition of the engine. The reaming and rectification work of the valve seat is generally carried out by means of the technique of reaming. The specific technical process is: selecting the appropriate arbor; removing the hardened layer; rough reaming, fitting; fine reaming; sealing inspection.

     When the valve seat of the valve device and the valve seat contact belt are worn wide or have ablation marks, they should be reamed. The valve seat reamer should be used for reaming. The following emphasis is placed on the process of reaming the festival as follows:

1. Select the appropriate reamer guide according to the inner diameter of the valve guide. The reamer guide rod should be able to tumbling inside the intake valve, but it should not be loose.

2. Select the air inner seat reamer according to the different angles of the inclined surface of the intake and exhaust valve seat, and fix the reamer on the guide rod.

3. The sanding valve seat contacts the hardened layer on the belt. Reaming generally causes the reamer to slip if there is a hardened layer on the valve seat contact ring. In this case, the hardened layer should be worn off under the reamer with a coarse sanding pad.

4, thick hinges. Use a thick reamer to ream the sealing bevel, apply even force to both hands, and roll gently until the defects such as ablation and mottle are hinged.

5, fine hinge. Use a fine reamer with the same angle to quietly tilt the bevel.

6. Reaming the width of the bevel. In order to reduce the width of the seal ring and adjust its precise orientation, the upper and lower ports of the valve seat can be reamed with 15° and 75° reamer respectively, so that the seal ring on the valve head is located in the middle or middle of the slope of the valve head.

The department is slightly inclined to the valve stem. When the valve seat seal has a tendency to the outside of the valve head, use a 15° reamer to hinge the mouth; if the seal ring is inclined to the valve stem, use a 75° reamer to close the mouth until it is suitable for suspension. Finally, the contact ring is hinged with a fine reamer, and the width is 1.5 to 2.5 mm.