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Stainless steel mesh belts are widely used in the glass manufacturing industry for use as mesh belts in annealing furnaces and firing furnaces. Food processing industry, dehydrated vegetables, frozen foods, pre-treatment conveyor belts for single-freezing machines, chain nets. Powder metallurgy, metal heat treatment, quenching, sintering, brazing, roasting, brightening, blackening, bearings, carbonitriding high-temperature furnace mesh belts, baffle-type mesh belts, conveying mesh belts for painting and drying lines, mesh belts for nickel foam reduction production lines, washers, elevators, dryers, curing furnace mesh belts. Various conveying process chains and conveyor belts. Structure of the mesh belt: A regular mesh belt consists of a mesh surface and shafts, while another type equipped with chains is made up of chains, support shafts, and the mesh belt itself. The production process of mesh belts: The equipment mainly consists of three machines – a wire-winding machine, a embossing machine, and an TIG welding machine. Ready-made materials of various thicknesses are available for use. Generally, the thickness of the wires used to form the mesh belt differs from that of the belt axis. The number of turns required for the axis is determined based on the width of the mesh belt, after which the wires can be wound around it. This allows for simultaneous production; once both components are ready, they are assembled by workers through spot welding, and the finished product is completed. Main factors affecting the service life of the mesh belt: 1. Material of the mesh belt (original Japanese materials offer a longer service life). 2. The purpose of the mesh belt furnace is for quenching or carburizing; the service life for carburizing is relatively short. 3. The quenching medium used generally results in a shorter service life for the salt bath conveyor belt. 4. There are mechanical issues with the design of the equipment itself. In the use of stainless steel mesh belts, ordinary belts begin to crack after 8 weeks of operation due to nitridation and carburization. Taking the traditional 314 stainless steel mesh belt as an example, a quenching and preheating treatment is generally carried out first: it is operated under normal conditions in flowing air at 870°C for 28 hours, after which the atmosphere is changed to N2-3%H2; the temperature is maintained at this level for 2 hours. Subsequently, the temperature is increased gradually over 14 hours to 1120°C, where it is held for 8 hours before the parts begin to be sintered. At this time, the atmosphere contains about oxygen, with a dew point corresponding to approximately 20 ppm of water vapor. But about 8 weeks later, the strap began to break. This is because the thin layer of chromium oxide on the surface of stainless steel is in an oxidized state in the preheating zone; once it enters the high-temperature zone, it becomes reducing, causing the surface oxides to be reduced. However, upon entering the cooling zone, although the atmosphere remains the same, the decrease in temperature causes it to become oxidizing again, leading to further oxidation of the conveyor belt. This cycle of oxidation and reduction results in damage to the material. Furthermore, in high-temperature areas, the graphite and lubricants present in the components of stainless steel decompose to produce CO, which leads to carburization. This CO reacts with the Cr in the stainless steel mesh to form chromium carbide, while nitrogen in the atmosphere also reacts with chromium to form chromium nitride. Both of these compounds are hard and brittle, which reduces the lifespan of the stainless steel mesh belt. The solution is as follows: if the dew point of the atmosphere is raised to 34°C, that is, to 260 ppm in terms of water vapor, the stainless steel mesh belt can still maintain a slight oxidizing property in the high-temperature area, and the oxides on its surface are not reduced. Furthermore, no decarburization occurred on the surface of the workpiece either.