I'm assuming you mean house pipe joints. Start at the pipe union, using a bigger pipe wrench if necessary. If the joint breaks you will have to replace the pipe. Unfortunately there aren't any real good tricks, it just takes a lot of force. you can try draining the pipe and adding heat, but don't get it hot enough to melt the galvanized coating otherwise you'll NEVER get the pipe off. If it's a gas pipe don't try putting heat on the line. That wouldn't be good.
You need a pipe wrench. Try to borrow-they are pricey.
Rusted cast iron.
If it is "rusted out" you do not repair it, You do replace it with XHCI
Hacksaw
first of all its wheel. and STRENGTH!
It can be. It is the past tense and past participle of the verb "to rust." Examples: Rusted steel is not as strong as the original steel. The Tin Man's joints were rusted, so he could not move.
The best method for sealing pipe joints is using Teflon tape.
Water constantly exerts pressure on pipe joints. I have seen old soldered joints flying apart when subjected to extreme pressure or trains passing nearby. This sometimes happens with plastic pipe also if joints are not thoroughly set .
The best type of pipe dope recommended by plumbers for sealing pipe joints effectively is a high-quality thread sealant compound.
With a wrench
Using a rusted galvanized pipe in a plumbing system can lead to potential risks such as water contamination, reduced water flow, leaks, and pipe corrosion. This can result in health hazards, damage to the plumbing system, and costly repairs. It is important to address and replace rusted pipes to maintain a safe and efficient plumbing system.
belt it with a slege hammer to see if that will loosen it up failing that it needs to be heated with a torch, to burn the rust then hit with a hammer to loosen