The Causes of Trim Box Stickiness in Shear Cutting of Cold Coil
Trimming boxes are vital tools in cold-rolling process. It is a special cutting tool used to reduce various widths of material and cut off excessive wide materials as scrap. Shear cutting of cold coil with trim boxes is a vital process used in the production of cold roll steel. Unfortunately, operators may experience a problem known as ‘trim box stickiness’ during shear cutting. In such cases, the roll material can become stuck to the the cutting edge of the trim boxes, making it impossible to continue cutting without further work. Trim box stickiness can cause undue time delays and affect productivity.
The causes of trim box stickiness can be complex and vary depending on the processing conditions and/or the material being processed. Generally, trim box stickiness can be caused by one or more of the following factors:
1. Operating Conditions – Potential causes of trim box stickiness may include excessive cutting speed, inadequate lubrication, poor quality of the start components (e.g. tools, dies), and inadequate trim box clamping force.
2. Material Properties – In some cases, the material being processed itself may cause stickiness. Steel of excessively low relative hardness, different dimensions of raw material, or presence of impurities (e.g. sulfur and carbon) on the surface of the material can all cause trim box stickiness.
The effects of trim box stickiness can be costly and may lead to unfinished work, machine error and potential failure, production line delays, and costly repairs or maintenance. It is therefore essential to identify and troubleshoot the root causes of trim box stickiness in order to prevent further production issues.
The primary way to prevent trim box stickiness is to improve operating conditions and/or the material being used in the cutting process. Adjustment of cutting speed and lubrication can prevent the material from melting or rubbing on the cutting edge of the trim box “stickily”. Quality examination and maintenance on the start components can also reduce the possibility of stickiness. Moreover, chemical composition examination and fatigue tests of raw material should be carried out before production starts.
In addition, the need to ‘pick-off’ melted material from the cutting edge of trim boxes should be minimized. This can be done by implementing a curve cutting operation, which reduces the possibility of residual material being left on the cutting edge as it lessens the cutting time.
In summary, trim box stickiness can be caused by several factors including operating conditions, material properties, and insufficient pick-off operations. To ensure production efficiency and minimize the potential of trim box stickiness, operators should properly review and manage the cutting conditions, monitor the start components, regular maintenance, and closely examine the material being used.
