Double-opening valves are commonly used sampling valves, typically consisting of two connected ball valves. Their advantages include safe and stable sampling. During sampling, first close valve A (closest to the equipment and pipeline), then open valve B to allow the medium to flow into the space between the two valves. Next, close valve B and open valve A, placing the sampling container in the sampling port to collect the sampled medium.
Classification of Sanitary Sampling Valves
Flanged Jacket Valves: The principle of a flanged jacket valve is that it seals through the cone at the top of the valve stem and the conical hole in the valve seat. During sampling, the valve stem is lifted using a handwheel to separate it from the conical hole, allowing the medium in the conical hole to flow into the external sampling container.
Sampling Valves with Insulated Jackets: When using sampling valves with insulated jackets, it is crucial to avoid forcibly opening the valve before the medium has completely melted. The valve must be opened only after the crystals inside have dissolved; otherwise, it may cause a safety hazard.
When using sampling valves with insulated jackets, it is also important to avoid forcibly opening the valve. If the valve cannot be opened, never use an extended lever, as this will cause excessive force on the valve, potentially leading to the valve core and stem detaching, or damage to the sampling components, resulting in a safety hazard.
