Shibata Satoshi
Mesh belts used in heat-treatment furnaces are exposed to severe operating conditions, including high temperatures, repeated heating cycles, the weight of conveyed parts, and continuous tension inside the furnace.
As a result, damage caused by heat and tension can occur after a certain period of use, making belt replacement necessary.
There are two main approaches to extending the lifespan of a heat-treatment mesh belt.
The first approach is to examine the damage condition of the currently used mesh belt and improve its specification accordingly.
A heat-treatment mesh belt is mainly composed of two types of wire: spirals and connecting rods.
The strength and durability of the belt are affected by specifications such as:
By examining how the belt has reached the end of its lifespan, it is possible to identify which parts should be reinforced.
The rods may become curved in a bow shape or deformed into a wavy shape. This may indicate that excessive load or tension is being applied to the rods.
Possible improvements include:
Reinforcing the rods may help reduce deformation of the entire belt and contribute to more stable conveying.
If spiral breakage, such as breakage from the belt edge or holes developing in the center section, is the main reason for the belt reaching the end of its lifespan, the spiral specification should be reviewed.
Possible improvements include:
However, simply increasing all wire diameters will increase the total weight of the belt.
A heavier belt may place additional load on the drive system and increase the tension applied to the belt itself, which could create other problems.
Therefore, it is also possible to adjust the strength balance between the spirals and rods while minimizing changes to the total belt weight.
Mesh belts are available in various constructions, including single spirals, double spirals, crimped rods, and straight rods.
The most suitable specification is not determined by operating temperature alone.
It is necessary to consider multiple factors, including:
At TWC, we inspect used mesh belts and damaged sections to identify the main factor limiting belt life.
We then review the wire diameter, pitch, weaving structure, and other specifications by referring to our past manufacturing experience with mesh belts used in a wide range of heat-treatment and conveying applications.
Based on this evaluation, we propose a mesh belt specification better suited to the actual operating conditions.
The second approach is to change the belt material to one that is better suited to the operating temperature and furnace atmosphere.
Heat-resistant stainless steels such as SUS310S and AISI 314 are commonly used in high-temperature heat-treatment processes.
However, when higher heat resistance or oxidation resistance is required, changing to a nickel-based alloy such as Inconel 601 may help extend the lifespan of the belt.
The most suitable material depends on factors such as:
Rather than simply selecting a higher-performance material, it is important to choose the most appropriate material by considering both the actual operating conditions and cost.
There are two main approaches to extending the lifespan of a heat-treatment mesh belt.
The first is to examine the current damage condition and review the wire diameter, pitch, weaving structure, and other specifications of the spirals and rods.
The second is to change from a heat-resistant stainless steel, such as SUS310S or AISI 314, to a material with higher heat and oxidation resistance, such as Inconel 601.
The key is not simply to make the belt stronger, thicker, or heavier.
It is important to identify the current failure mode and reinforce the necessary areas while also considering the total belt weight and the load placed on the equipment.
Selecting an appropriate material according to the operating temperature and furnace atmosphere can also contribute to a longer belt lifespan.
When you are experiencing lifespan or damage issues with a heat-treatment mesh belt, TWC can review the used belt condition and operating environment and discuss possible specification improvements.