I just want to know if indeed valves used on fire fighting pipelines or fire hydrant pipes have left hand threads so have to be opened clockwisely as against regular valves which are opened anticlockwise. And the reason for this.
In a career over 25 years dealing with fire equipment, almost all fire equipment valves are 1/4 turn ball valves. The chief exception to this is valves that are larger than 2.5". These are designed to open and close slowly to prevent water pressure spikes from destroying things. All of these valves have handle systems that open counterclockwise.
Why? Because many firefighters just ain't that smart at mechanical things.
Yes, as said by Bob, universally opening the valve is 'counterclockwise'. This has to be more so for fire fighting equipment/valves, else there is possibility for the valve getting jammed on trying to open by counterclockwise, habitually.
Rightly said, lager valves need finer control, hence use to be globe valve. Angle globe valves are suitable for most locations.
Hope 'guest' is not confused by looking at some valve spindles which are 'left hand threaded'. Raising spindles have 'right hand threads' and 'non raising valve spindles' are 'left hand threads'. By so only, counterclockwise rotation will open and clockwise will shut any type of valve as to avoid confusions...
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A picture worth thousand words: needless to say if it is animated.
For Facilities that have firefighting equipment installed in them, you don't want someone checking the valve to ensure it's closed and inadvertently open it instead.
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Why is there never enough time to do it right the first time but always enough time to do it over?