Causes And Solutions For Sintering Furnace Mesh Belt Deformation

Minor thermal elongation of stainless steel mesh belts during high-temperature sintering is a normal material property and does not belong to abnormal deformation. In actual production, irregular deformation including bending, distortion, unilateral stretching and fracture severely affects the stability and service life of sintering furnace conveyor belts. This article summarizes the key causes and practical optimization solutions for such failures.

Improper material selection is the primary cause of premature mesh belt deformation.

Many manufacturers adopt common 304 stainless steel with a temperature resistance of 870°C for high-temperature working conditions above 1000°C, instead of high-temperature resistant 310S, 314 or Inconel alloys. This leads to rapid grain growth and sharp strength decline, causing irreversible plastic deformation.

Besides, raw materials with excessive carbon content and impurities weaken grain boundary strength at high temperatures. Unqualified wire processing without double drawing and double annealing fails to eliminate internal stress thoroughly, resulting in insufficient toughness and poor flatness of the mesh belt.

Uneven furnace temperature is another critical factor.

Though over-temperature operation is rare in modern factories, inconsistent heating element arrangement and poor furnace insulation create alternating high and low temperature zones. The unbalanced thermal expansion generates internal stress beyond the material's yield strength, triggering local bending and distortion, especially in gas-fired sintering furnaces.

Mechanical and physical errors also account for most operational deformations.

Excessive tension during installation causes over-stretching under high temperature and load. Asymmetric tension adjustment and uneven material distribution lead to unilateral sinking and stretching deviation. In addition, mismatched pitches of spiral strips and cross rods cause irreversible one-sided deviation that cannot be corrected by tension devices.

Harsh sintering atmospheres accelerate belt aging and deformation.

In nitrogen-based environments, carburization and nitriding reactions precipitate chromium carbides and nitrides, embrittling the material and reducing structural strength. Repeated oxidation-reduction cycles destroy the protective chromium oxide layer, while high-temperature alloying reaction with copper materials and corrosive gas erosion further harden and damage the mesh belt.

Improper model selection, non-standard installation and insufficient daily maintenance exacerbate failures.

Professional specifications including K2, F2, RRW and A4 must be selected according to material size and load capacity. Standard operating procedures for installation and heating commissioning are essential. Regular cleaning of oxide scale and inspection of belt joints are also required.

To extend mesh belt service life, enterprises shall select matched high-temperature alloys based on working temperature, stabilize furnace temperature uniformity, standardize installation tension, ensure uniform material feeding, and implement routine maintenance and deviation monitoring.