Snyder Mushroom Vent
Proper venting of polyethylene storage tanks ensures safe operation and also extends the useful life of the tank. Excessive pressurization of a polyethylene tank can lead to tank damage and can create an unsafe working environment. In many cases people simply put a vent on a tank that is the same size or one size larger than the fill or discharge line as a standard venting practice. That works fine if the tank is being filled or emptied by a mechanical pump. However, tanks are often being filled by a tanker truck pneumatically (using air pressure). When this happens, the chance for a surge of pressurized air entering the tank increases which can result in over-pressurization when the vent is undersized. Snyder offers U-Vent assemblies up to 6” size. This works fine for many cases and multiple vents can be added if more venting is required. However in some cases, depending on fill line size and the psi used to offload the tanker, a 6” vent is not adequate to evacuate the ACFM (Air Cubic Feet per Minute) entering the tank and multiple vents may not be a viable option.
As a solution to the undersized venting problem, Snyder has developed a rotationally molded 18 inch Mushroom Vent that can be installed on the top of new or existing tanks. This vent attaches to any polyethylene tank that has at least 19” diameter of flat area simply by cutting the hole and attaching it with 8 screws and sealing it with silicone. The underside of the vent comes standard with 1/8” mesh poly insect screening. The 18” Mushroom vent ensures that your tank will not be excessively pressurized in the event of an air surge during normal pneumatic filling.