The removal method decides the price. Cutting a stem to save ten minutes costs more than the ten minutes are worth.
Isolate, drain and decontaminate first
Every removal starts with isolation and decontamination, both for safety and because a valve full of process residue cannot be assessed. A valve that arrives with product in the body has to be cleaned before anyone will look at the trim.
Keep the decontamination record with the valve if your site produces one. It is part of the paperwork a buyer wants to see.
Unbolt, do not cut
Flanged valves come out by unbolting. Cutting the pipe either side of a valve destroys the spool pieces and often damages the flange faces, and it saves very little time on a planned removal.
Where a valve is welded in, cut the pipe well away from the valve body and leave a stub on each end. A valve with weld stubs is still a valve; a valve with a gouged body is not.
Never cut the stem
The stem is the most commonly damaged part in a rushed removal. Cutting it to free a seized actuator converts a complete valve into a body and bonnet, and removes most of the value.
If an actuator has to come off, unbolt it from the yoke and keep the coupling. If the stem is seized, leave the actuator on and tell the buyer. A seized assembly is a repair job; a cut stem is a loss.
Handle the flanges
Flange faces are machined sealing surfaces. Do not drag valves across concrete on their flanges, do not drop them, and do not use a flange face as a lever point. Fit plastic or timber caps if the valve is going into storage for a while.
A single deep gouge across a raised face can require re-machining, which changes the value of a large valve significantly.
Store it the way it will be sold
Valves stored closed keep their seats protected. Butterfly valves stored slightly open keep their liners from taking a set. Actuated valves stored upright keep water out of the instrument.
A little care at the point of storage is the cheapest value protection available, and it costs nothing but a decision.
Questions sellers ask
Can a cut stem be repaired?
Sometimes, by replacement, but the cost usually exceeds the value difference. It is better not to cut.
Should valves be stored open or closed?
Closed for gate, globe and ball valves. Slightly open for butterfly valves to protect the liner.
Do you buy valves with damaged flanges?
Yes, as body and bonnet, at a reduced price.