Processing Small Screw Thread Problems and Solutions
Small screw thread machining is an important part of machining and assembly. With the increasing complexity of small screw threads, problems are becoming more and more common. This article will discuss some of the common problems encountered in small screw thread machining and their solutions.
Firstly, unqualified surface quality. This is the most common problem encountered in the machining of small screw thread, which will increase the difficulty of the insertion process, and the threads are easily blocked during the processing. The main reasons leading to this phenomenon are: improper choice of cutting tools, which cannot guarantee the cutting speed and surface finish; excessive cutting speed, resulting in poor surface finish; unsuitable cutting parameters;uneven wear and tear of cutting tools, causing ununiform cutting pressure, resulting in uneven surface properties of the thread surface.
In order to solve the problem of unqualified surface quality, for the choice of cutting tools, it is necessary to choose suitable cutting tools according to the material and process parameters of the parts, and the reasonable cutting speed should be observed in the cutting process. If too much cutting is caused by unreasonable parameters, reasonable parameters should be selected again according to the shape, size and material of the parts. At the same time, the wear and tear of cutting tools should be checked and replaced in time.
Secondly, the machined thread has too large size. Since the manufacturing accuracy of the parts is limited, the thread cutting machining process can not guarantee the machined thread size. The main reasons are too small cutting force, which will cause too small size; the curvature of cutting edge is too small, resulting in insufficient cutting force, which will also cause the thread machining too big; the guide deformation of rotary motion parts will also cause the machined thread too large; the wrong gap size or inaccurate positioning of the tool holder, or the wrong choice of the cutting tools and so on.
To solve the problem of too large machined thread, it is necessary to select the cutting tools which is suitable for the material and shape of the parts. All machining parameters should be optimized to ensure the cutting force, while the curvature of the cutting edge should be adjusted properly. In addition, inspection should be added after each positioning of the guide and tool holder, and regular inspection of the tool holder accuracy.
Finally, the thread tool is easy to break. This is mainly related to the strength of the cutter body and the selection of cutting parameters. Low strength of cutter body will easily cause the tool to break; and improper cutting parameters may result in high cutting force and vibration force, resulting in the breakage of cutter body.
To solve the problem of easy breaking of thread tool, it is necessary to select the thread tool with high strength and reasonable parameters. At the same time, the cutting speed and feed rate should be optimized according to the material of the tool and the machining requirements, and pay attention to the effect of cutting fluid and coolant.
