Replacement time of gate valve after life time over ? But my question is normally with in how many years we replace gate valve.

If a gate valve is used properly, it will outlast u and possibly your children.

If a gate is not opened all the way, water passing gate will wear a groove in it. This will cause the valve not to shut off.

If valve is installed with handle down and rod attached to gate separates, gate will still operate. If rod separates and handle is above pipe, gate will drop and not be able to raise when valve is opened.

I know that plumbers do not normally install the way I do, but everyone needs to work. Unless this is against code this is way I would install a gate valve. And remember always open all the way.

Good luck

Chuck