three-way valve

Guarantee?

Not possible with only a single isolation.

What's the issue here?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

Flow will go from higher pressure of the 2 input streams to the lower pressure system.

I am afraid that the valve symbol does not explain what kind of valve I have in mind. I am therefore attaching a link to this type of valve.

My case starts from 1 minute.
From 1.13 starts another example, but here it is a little better, because the blind flow is to the lower port which is basically just a pipe.
For the 1 minute situation, the flow reaches the ball casing. There is a risk of milk retention when the flow is stopped. Valves are also mounted horizontally.

The issue is whether this is acceptable? What is general practice? Butterfly valve assembly in front of blind flow? I would be grateful for all replies and technological clarification. Maybe some answers from people who have worked in the food industry?
I rule out opening the valve due to high pressure.
I know the risk about accidental opening.

It seems that the vendor is to show the operation of the various type of valve products for the possible process applications. If a concern of the contamination due to the two possibly mixed flow, a double block and bleed valve (video @2:25) may be used to mitigate the issue.
For the process safety management, the operation needs to consider the event likelihood and possible consequences for the process design and determine the number of the safety guides as required for it.

In the food, beverage and medical industries the design of the piping around the valve is as important as the valve itself because you need to eliminate dead pockets where contamination can develop. This would include the orientation of the valve itself and if you are paying the premium to purchase sanitary valves you should follow the manufacturer's guidance on the installation - including orientation.

In the video you linked there are nozzles on the lower section of the valve that are probably aimed at facilitating draining and flushing the valve cavity. This type of operation is usually driven by a control system that will automatically drain and/or flush the valve after a particular operation.

The degree to which you need to provide draining and flushing facilities will of course depend on the actual product that you are processing. Some applications require extreme care and can involve multiple flushing cycles to ensure sanitary conditions.

Katmar Software - AioFlo Pipe Hydraulics

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