1. Check the mechanical properties of the tuyere before installation.

a) The movable parts of the tuyere are required to move freely, with uniform damping, and without jamming and loosening.

b) Products with adjustable or detachable guide vanes require convenient and reliable adjustment and disassembly, and no looseness after positioning.

2. The external decorative surface of the tuyere should be flat, the distribution of the diffusion ring should be even, the color should be consistent, and there should be no obvious scratches and indentations.

3. The allowable deviation of the tuyere should meet the requirements of Table 2.