Grinding is a method of finishing, and grinding waste are rarely seen. Due to the dimensional accuracy of the valve sealing surface, grinding waste is even rarer. Frequent occurrences of sealing surface grinding are irregularities in geometry, surface scratches, and grooving. Common defect forms, causes, and prevention methods are as follows.

List of content for this article：

1. Difference defects form for industrial valves,

2. Prevention methods and maintenance for different defects.

Defect form: scratched, napped

Cause one: the abrasive is mixed with individual coarse abrasive grains.

Prevention Method 1: The abrasives can be sorted by adding water precipitation method, and the maintenance of abrasives can be strengthened.

Cause 2: Dust, iron filings or other debris in the abrasive

Method 2: Containers containing abrasives should be covered and kept clean during configuration

Cause three: the part is not clean or has burrs

Prevention Method 3: The sealing surface should be deburred and cleaned before grinding.

Cause 4: Grinder or lap is not clean

Method 4: The first research machine is best separated from the fine grinding machine, and the cleaning machine and the rig are cleaned.

Cause 5: excessive dust in the workshop

Prevention Method 5: Establish a closed grinding chamber and keep the room clean

Defect form: knife mark or pull groove

Cause one: the quality of the previous process is not good, the luminosity is too low

Prevention method 1: The part should be ground before grinding, and the luminosity should not be lower than ▽6 when using the finishing vehicle.

Cause 2: Abrasive material is too thick

Prevention Method 2: Use fine abrasive

Cause three: the cutting heat generated during grinding is too high

Prevention Method 3: Reduce the grinding pressure, reduce the grinding speed and often add abrasive

Defect form: geometry is incorrect

Cause one: improper grinding movement

Prevention Method 1: Improve the grinding movement

Cause 2: The abrasive is too thick or unevenly coated

Prevention Method 2: Use a thinner abrasive and pay attention to a uniform coating

Cause 3: uneven grinding pressure

Prevention method three: the force should be uniform when grinding by hand

Cause 4: Poor precision in the previous process

Prevention Method 4: Improve the machining accuracy of the previous process and pay attention to prevent the part from deforming

Cause 5: Grinding time is too long

Prevention Method 5: Reduce the grinding allowance, try to use coarser abrasives or increase the grinding speed and increase the grinding pressure

Cause 6: The rig is not accurate

Method 6: Check and repair the rigs frequently. When the lap is too fast, you can use other wear-resistant materials.