The utility model relates to a mechanical self-supporting device, which is suitable for ventilation and air conditioning systems requiring a fixed air volume. The air volume control of the constant air volume valve does not require external power, and it relies on the air force in the air duct and the valve disc, air bag, spring plate and CAM of the valve to control the position of the valve blade and keep the air volume constant.

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  CCCF certified products

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  CMA metrological certification

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  National quality supervision, inspection and certification

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  China recognizes the joint symbol of international mutual recognition

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  China recognizes the joint symbol of international mutual recognition