Why Lathe Machines Need To Release Mechanical Stress

MAXNOVO MACHINE Tips :  Machining is the general term of turning, milling, drilling, planing and grinding. Common point of these applications is the cutting process that heats the surface of the material due to the friction and forms chips. As a result, in the machinery industry, it's widely acknowledged that releasing stress in machine tools is crucial, especially for high-precision models. There are many kinds of lathe machine, they include the CNC Lathe, Metal Lathe, Conventional lathe, horizontal lathe, vertical lathe, bench lathe, engine lathe, heavy-duty lathe machine and etc. All these lathe machines all needs to Release Mechanical Stress.

This article delves into why stress release is necessary, the duration required, and the methods employed to achieve it.  

1. What is Mechanical Stress ?  

Stress occurs when an object deforms due to external factors like force, humidity, or temperature changes. The internal forces within the object interact to counteract these external influences, striving to restore the object to its original shape.

In the machinery industry, stress release is crucial for high precision lathes and machine tools. During the hot forming process of components like the bed, mechanical stress can develop. High-precision machine tools require accuracy at the micron or nanometer level, making it essential to release stress to prevent deformation errors that can impact accuracy. In simpler terms, stress release is necessary to maintain the accuracy and stability of high-precision machine tools by preventing deformation caused by internal stress during hot processing.

2. How Long Should Stress Be Released ?  

Traditionally, it is often to use static methods to release stress.

Some manufacturers would submerge castings underwater or bury them to ensure complete stress release.

The duration for stress release varies, ranging from several months to several years, depending on the metal components, their volume, and shape. The release environment must be carefully considered to avoid extreme conditions that could compromise the process. With technological advancements, new methods have emerged, significantly reducing the time required for stress release.

3. How to Release Stress ?  

Static Method is one of the methods for releasing stress, but this method is now used less and less. The reason is that static method release of stress takes too long time.

Some new techniques have been developed to release stress more efficiently. Stress release is generally performed before assembly, with the assembled machine allowed to rest for 10 to 20 days.

High-precision machine tools often use materials like marble, which are less prone to stress, for their beds. Metal machine tools now utilize methods such as shot peening, vibration, and rolling. 

• Shot Peening :  Pellets bombard the work-piece surface, implanting residual compressive stress.

• Vibration :  A vibrator creates resonance with the work-piece to eliminate stress.

• Rolling :  Rolling tools apply pressure to the workpiece surface, reducing stress.

• Other methods include heat aging, explosion techniques, thermal shock aging, and acoustic wave aging. 

In conclusion, releasing mechanical stress in machine tools is very important for maintaining high precision and high stability. With various methods available, the process can be tailored to the specific requirements of the machines and its components, ensuring better performance. 

For more than 35 years, our company of MAXNOVO MACHINE (www.maxnovocnc.com) is always focused on the development, design and production of high precision CNC Machine and Metal working Machinery. Feel free to contact us to get your Professional Solutions .