Problems and solving problems in the manufacturing process of the ventilation

(1) phenomenon: sheet surface is not smooth, uneven thickness, there are significant indentation, cracks, trachoma, scarring and rust, etc .; duct surface sinking, lateral protruding prominent deformation.
  (2) Hazard: When the system is running, the air duct leaks, resulting in undue air conditioning load loss, and affect the life of the duct; duct surface shaking, resulting in noise.
  (3) Analysis: Before the production of air duct, there is no quality inspection of the materials used; no measurement of steel plate thickness.
  (4) control measures: first check the material factory certificate of authenticity and material quality, and then check the material appearance; measurement of steel thickness.
Duct angle, twist and elbow angle is not correct
  (1) phenomenon: rectangular air duct is not parallel to the two planes, both ends are not parallel; angle is not straight; diagonal unequal; bite lax.
  (2) Hazard: the air duct will not connect the force, after the installation of the duct is not straight, the flange gasket is not tight, the system air leakage, resulting in air conditioning load loss, and shorten the service life; The air outlet is installed correctly.
  (3) Reason analysis: board laying is not correct; ducts parallel to each other, the opposite side of the sheet length and width are not equal; duct at the four corners of the mouth width is not equal; bite the mouth set up parts of the error, manual Biting strength is not the same as the mouth; did not take the appropriate reinforcement measures.
  (4) Control measures: start the cutting, the sheet should be strictly square, the length of each sheet, width, and maintenance diagonal, so that their deviation in the control of the agreed range; , The pipe should be opposite the surface of the two sheets together, repair size correctness; sheet bite mouth reserved size must be accurate to ensure that the bite width consistent; bite seam located in the four corners of the site, When the seam, with a wooden hammer first bit at both ends of the central part of tighten, and then along the whole length of the average play; the implementation of national standard "ventilation and air conditioning construction and acceptance of norms" of the delineation.