Monthly Archive November 24, 2021

Method for removing side burr of CNC machining parts

In the process of machining precision mechanical parts, there are often burrs on the side of the parts to be removed. If they are not removed in time, the machining accuracy of the parts will be affected, and the side burr jaws will not be clamped, resulting in danger. There are many ways to remove the burr on the measuring surface of parts. Let’s see how to remove the burr on the side of precision mechanical parts

The choice of deburring tools will be different when machining precision mechanical parts with different materials. General aluminum processing can directly remove burrs with a sharp knife; Special chamfering machine can be selected for steel processing, and chamfering knife can also be used for deburring on the machine tool; The deburring of POM material is more convenient because the material has no hardness and can be completed with a special saw blade. Many precision parts have special requirements for deburring, and the surface of parts cannot be scratched, so special attention must be paid to deburring!

The above is how to remove the burr on the side of precision mechanical parts. Thank you for sharing!

ken. tang@chengcg.com

Introduction to CNC machining accuracy

In the machining process of precision mechanical parts, the following points are introduced to control the machining accuracy: geometric accuracy refers to the accuracy of geometric shapes such as surfaces or axes of parts, such as whether the line is straight, whether the surface is flat, whether the normal sections on the cylinder are round, etc. The allowable variation range is represented by “geometric tolerance”. The smaller the geometric tolerance number, the higher the shape accuracy; Dimensional accuracy: dimensional accuracy refers to the accuracy of the dimension of the part after machining, expressed in “dimensional tolerance”. When the dimensions of parts are the same, the higher the accuracy, the smaller the tolerance number; Positional accuracy: positional accuracy refers to the accuracy of the mutual position between the surfaces of the parts, such as whether the two planes are parallel, vertical, coaxial, etc., expressed in “positional tolerance”. Holding these points, the machining accuracy of precision mechanical parts is easier to control.

The above is a brief introduction to the machining accuracy of precision mechanical parts. Thank you for sharing!

ken. tang@chengcg.com

Introduction to CNC machining auxiliary fixture

In the field of machining industry, some complex parts are difficult to process, and auxiliary fixtures will be used to process them. There are many kinds of auxiliary fixtures to see the difference:

First, understand the general fixture: the general fixture refers to the fixture that has been standardized and can be used to process different workpieces within a certain range. For example, three jaw chuck and four jaw single action chuck on lathe, flat pliers, indexing head and rotary worktable on milling machine, etc. This kind of fixture is generally produced by professional factories and often provided to users as machine tool accessories. It is characterized by wide adaptability and low production efficiency. It is mainly suitable for the production and processing of single and small batch parts; Special fixture: special fixture refers to a fixture specially designed for a certain process of a workpiece. It is characterized by compact structure, rapid, convenient and labor-saving operation, which can ensure high parts processing accuracy and production efficiency, but the design and manufacturing cycle is long and the manufacturing cost is high. When the product is changed, the fixture will be scrapped because it can no longer be used. It is only applicable to production and processing with fixed products and large batch; Universal adjustable fixture and group fixture: it is characterized in that some components of the fixture can be replaced and some devices can be adjusted to adapt to the processing of different parts. The fixture used for group machining of similar parts is called group fixture. Compared with group fixture, the machining object of universal adjustable fixture is not very clear, and the scope of application is wider.

There are also combined fixtures: combined fixtures refer to fixtures assembled from a set of pre manufactured standard components and parts according to the machining requirements of mechanical parts. Manufactured by professional manufacturers, it is characterized by flexibility, versatility, short manufacturing cycle and repeated use of components. It is especially suitable for trial production of new products and single piece small batch production and processing. Traveling fixture: traveling fixture is a fixture used on automatic line. The fixture should not only clamp the workpiece, but also be integrated with the workpiece, move from one station to the next along the automatic line, and process different processes.

In the process of machining mechanical parts, they are classified according to the machine tools used: due to the different working characteristics and structural forms of various machine tools, different requirements are put forward for the structure of the fixtures used. According to the different machine tools used, fixtures can be divided into: lathe fixture, milling machine fixture, drilling machine fixture, boring machine fixture, grinder fixture, gear machine tool fixture and other machine tool fixtures. Classification by clamping power source: according to the different clamping power sources used by the fixture, it can be divided into: manual fixture, pneumatic fixture, hydraulic fixture, gas-liquid fixture, electric fixture, magnetic fixture, vacuum fixture, etc.

The above is the introduction of auxiliary fixture for machining mechanical parts. Thank you for sharing!

ken. tang@chengcg.com