There are several surface treatment methods for CNC precision machining

CNC precision machining is a technique for precision machining with computer digital control, and the machining range is wide. CNC precision machining will occasionally carry out surface treatment according to the environment, so let's take a look at the surface treatment skills of CNC precision machining.

First, manual punishment: such as scraper, wire brush or grinding wheel. The rust and oxide skin on the surface of the workpiece can be removed by hand, but the manual treatment is labor-intensive, low in production efficiency, poor in quality, and not thoroughly rinsed.

Second, chemical treatment: The main purpose is to use acid-base solution to react with workpiece, oxides and oil on the surface, and then dissolve in acid-base solution to remove oxides and oil on the surface of workpiece. Then wash with nylon cloth and stainless steel wire brush.

Three, machine punishment: mainly including wire brush roller polishing, shot blasting.

1. The polishing technique is that the brush roller is driven by a motor, and the brush roller is twisted at high speed on the high and low surfaces of the belt in the opposite direction to the action of the rolling piece. The washed iron oxide flakes are washed away by the closed circulating cooling water flushing system. Shot blasting is a technique that uses centrifugal force to accelerate a projectile and radiate it into the workpiece to remove rust.

2. Shot peening is divided into shot peening and sandblasting. The surface treatment of shot peening has a great influence, and the flushing effect is obvious. However, shot peening is easy to deform the thin plate workpiece, and steel shot peening will affect the surface of the workpiece and deform the metal base. Since Fe304 and FE203 are not plastics, they will peel off due to cracking, and the oil film will deform with the workpiece. Shot peening cannot completely remove the oil from the workpiece.

1. Benchmark first. The datum surface is processed first. During the machining process of the parts, the appearance as the positioning reference must be processed first, so as to provide the reference for the processing of the subsequent process as soon as possible.

Second, separate processing stages. The appearance with high precision machining quality requirements is divided into processing stages, which are generally divided into three stages: rough machining, semi-finishing and finishing. The key is to ensure the quality of processing, the placement of the heat treatment process that is beneficial to the scientific use of equipment, and the discovery of blank defects.

Three, face first and then hole. Box, bracket, connecting rod and other components should be machined flat first, and then machined holes. In this way, the processing hole can be positioned by the plane, which ensures the positional accuracy of the plane and the hole, and facilitates the processing of the flat face.

Fourth, finishing. Light processing of the main surface, such as fine grinding, rolling and other processing. Should be placed at the end of the craft path. The general guidelines for defining the machining process of tight parts, and the specification for the machining process of tight parts can be roughly divided into two joints. First, the process path for parts processing is determined, and then the process size, equipment and process equipment used, cutting standards, working hours quota, etc. of each process are determined.