Dummy Valves are utilized in production tbg for the purposes of having a plug or blank till the operator knows the flow conditions and surface components to size down hole GLVs.
If you are looking for a remedial gas-lift method, consider to punch a check valve in the tubing using conventional slick-line. It delivers a reliable gas-lift valve and don't require to re-complete the well.
To add to dalbo comment
punching tubing will not allow us to prorperly desgin the unloading valve
my experience: we have to install a gas lift pack off in front of hole for th unloading valves. Problem: wireline restriction , can not access deeper tubing without pullling the pack off. Moreover after some time it would be difficult to pull out the pack off
But for last sollution (before recomplete the well) punching tubing would be a option
To clarify dalbo and nasution comments....
Punching a check valve in the tubing is not punching THE tubing. The check valve is an actual one way valve with retaining ball that can be of a number of dimentions. Although you have to consider it a temporary solution, we use it to gather real infos on well behaviours prior to pulling the completion and in some istances tey lasted years!!
1-)initially in a system will produce natural flowing for a certain long time / then later replaced with active valves allready designed initially and spaced but replaced temporary with dummies
2-)used when you get wash out for mandrel holes and less cost than pst valve or get cut for pst rubber
3-) used when you replace your turbine with higher discharge gas pressure, so a selective valves in system will be replaced with dummies and other will replace with higher setting pressure
4-) in some cases upper valves suffering from reopening problem as the people try deepining p.o.i and not care with design operating pressure, so upper valves reopening and they solve this problem by replacing upper valves with dummies to avoid drop in production or circulating lift gas.
