You carefully cut the pipe, then if you can push it apart enough to fit one nut and one'olive on each end of the pipe. Now seat both ends in the union. At this point you hold the centre of the union with a wrench and tighten each end nut while pushing the pipe in towards the union. When both ends feel tight, hold each end nut with a wrench and give one final 1/4 turn. That was with a standard brass union, now you can also fit a 'sharkbite' with no wrench, just firmly pushing each end in. With 'sharkbite', however you MUST make sure the pipe ends are smooth and have no sharp edges.
You need at least a 3 in. pipe -- shower is 2 in. pipe
Call a pumer
Yes you do and it needs to be inspected.
Install an automatic air vent on the line
Install a ty fitting on the stack in the basement then run it to the sink. Put it low enough to account for a fall in the pipe, to allow proper drainage. Be sure to install a waste and vent pipe to code for both fixtures.
WeldBrazeTap and plugCut out and install a union
It joins two pipes together, never install one where you cannot get to it latter if you have too.
Start with one of the pipes you are connecting together. I usually start with the female half of the union. The half that has the nut on it. Slide the nut over the pipe first so you don't forget it. Use pipe dope or teflon tape on the threads of the pipe. Screw on the female half of the union and tighten it with two pipe wrenches, holding the pipe with one of them. Put the other half of the union on the second piece of pipe you are connecting and tighten it. Now bring the two halves of the union together and screw on the union nut. Do not put any pipe dope or tape on the union itself. It is a dry fit. Tighten the nut while holding the male half of the union. The second half of the union. -- I always put pipe dope on the union, it helps the union tighten more and it helps keep the threads from corroding together over time, making taking it appart easier.
on a hoist
No. Australian pipe threads are metric and the US is not.
You need at least a 3 in. pipe -- shower is 2 in. pipe
The pipe usually goes under the slab.
Union pipe layer makes $22/hr
Yes
Call a pumer
Cut it in the middle and replace it with 2 pieces with a union connecting them together.New answerIf the galvanized pipe is used for Vent or waste and your local codes permit YOU can cut the pipe remove it and install a shorter piece connected with a NO HUB Coupling. If the pipe is used for potable water cut out the galvanized pipe use a dielectric nipple then use a female x copper adapter to prevent electrolytic action
I would install studs, or struts, on each side of the pipe in question.