Many years ago we would freeze water lines with potato sacks (burlap bags) and dry ice. We have come a long way since then.
I can remember some of the first freeze kits that where introduced on the commercial market place. They had foot long bags that used liquid nitrogen. The problem with this method is, if you had a broken valve on a long run you could easily use the device because of all the room you had to work with. If you had to freeze the line in closer quarters you had to turn off the main water line and complete the task without freezing.
In the last few years many companies have introduced a variety of freeze kits that work great with practice. I have tried the Portable freeze kit with C02, and the liquid nitrogen freeze kit. I was not pleased with them because of longer and wider bags you had to wrap the line with.
The one I was most comfortable with is the cold-shot pipe freeze kit with carbon dioxide (C02). See picture.
When you use this kit to freeze lines insure you have your safety equipment ready to go. See pictures.
Don’t forget your tools.
With any freeze kit certain industries and the men working in those industries may use different freeze methods because of the type of material they are freezing.
My work was mainly freezing lines in hospitals because that is where I mainly worked. Freezing water and steam lines was the only way to repair a broken valve without shutting down a hospital wing or the entire hospital.
How to freeze a water line:
The first step before you begin to freeze any water or steam line is to know what type of material your freezing. With the cold shot pipe freeze kit you can freeze steel, copper, cast iron, aluminum, and plastic. I have never needed to freeze cast iron or plastic.
The second step is to insure you know where the main valve is located. Either a branch valve or a main valve in case you did break the line when freezing.
The third step is to find out when the best time of day would be best for the department your effecting to freeze the water or steam line, just in-case you were to break something. You may not have the luxury to determine the best time of day because you probably will need to do the work (ASAP) as soon as possible.
The fourth step is to use the buddy system which is having two trained plumbers who know what they are doing.
The next steps require you to prefab as much as you can before you cut the line. This could be soldering a valve with two pieces of pipe at each end and slipping into place after freezing, or threading a valve on a piece of pipe to connect to the water or steam line after freezing.
One other item I like to have handy is a flood bucket with accessories. See picture.
You should have everything in place before you begin like safety equipment, prefabbed piping, extra bottle of C02, location of shut off valve in case of an emergency, tools and a good partner and your ready to begin.
Follow the instructions on the freeze kit in regards to distance you must place the cups away from were your soldering. Normally you want to be at least 18 inches away from the joint your going to solder and this also depends on the size of pipe your soldering.
One person is doing the repair and the other is controlling the freeze operation by monitoring the color of the pipe once it begins to freeze. Make your cut, install your new piece of piping while maintaining constant vigilance that the pipe is frozen and not over frozen where it will break.
Once you have your piping material back on line slowly turn off the C02 and allow the frozen line to thaw while maintaining vigilance that there are no leaks.
Your know back on line and you’ve made a repair saving thousands of dollars for your employer. Great job.
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