The acceptance of the processing and manufacturing quality of ventilation ducts shall be carried out according to their materials, system category search and different places of use, mainly including the material, specification, strength, tightness and appearance quality of finished products of air ducts.
The acceptance of the processing and manufacturing quality of ventilation pipes shall be carried out in accordance with the provisions of the design drawings and this standard. The purchased air ducts selected in the project must also be provided with corresponding product qualification certificates or verified for strength and tightness. Only those meeting the requirements can be used. Allowable air leakage of system air duct: the large allowable air leakage per unit area and per unit time specified by the air duct system category.
(1) Air leakage rate: the ratio of air infiltration or leakage under working pressure of air conditioning equipment, dust remover, etc. to their rated air volume.
(2) Purifying air conditioning system: used for air conditioning and air purification systems in clean spaces.
(3) Light leakage detection: use a strong light source to conduct light transmission inspection on the seam, joint, flange and other joints of the air duct, and determine the leakage position and quantity of holes, gaps, etc.
(4) Working pressure of air duct system: it refers to the large working pressure designed at the main air duct of the system.
For the acceptance of the specifications of ventilation ducts, the outer diameter or outer side length shall prevail for air ducts, and the inner diameter or inner side length shall prevail for air ducts. The specification search of ventilation pipe should follow the regulations of. The basic series shall be preferred for round air ducts. Irregular oval air duct refers to rectangular air duct, and the side length of long diameter plane and short diameter dimension shall prevail.
The air duct system is divided into three categories according to the working pressure of the system. The classification shall conform to the surface galvanized steel plate and various steel plates with composite protective layer. Seam connection or riveting shall be adopted, and welding connection methods that affect the anti-corrosion performance of the protective layer shall not be adopted.
The sealing of air duct shall be mainly based on the sealing of plate connection, which can be sealed by sealant caulking and other methods. The performance of the sealant shall meet the requirements of the use environment, and the sealing surface should be set at the positive pressure side of the air duct.