A novel range of automatic relief valves from Brownell can prevent vacuum or pressure build-up in sealed containers. Even slight variations in ambient temperatures can result in excessive vacuum or pressure generation, and in some cases the vacuum will prevent opening of the container. Deterioration of gaskets used for sealing is also increased. This variation in pressure should not be underestimated, for example a surface area of 0.5m2, with applied pressure of 0.07kg/cm2, will result in a loading of 350kg – the equivalent of seven bags of cement. The pressure and vacuum build-up is automatically equalised using the Brownell relief valve. The standard opening pressure and vacuum is 0.07kg/cm2, with s nominal flow rate of 0.5m3/min. Installation is quick and simple by using a locking ring or pipe mounting interface adapter supplied.
