Copper L pipe going bad after 20 years?

[ultrarunner]

I have a lot of copper pipe at the Hospital in the 1995 addition

The steam lines are all copper L and sizes range from 3/4 to 1 1/2" and brazed joints. The pressure is 65 psi which provides the 60 psi needed to run the sterilizers...

First 20 years zero problems...

The last 24 months I have had 6 pin hole leaks develop at various locations... only one was an elbow... so 5 of the leaks were simply in the pipe with nothing around...

Just seems odd for copper L to fall apart... the pipe is stamped made in USA

Anyone care to speculate?

 

[bcp]

My house has the same problem, after about 40+ years. All leaks have been pinhole leaks between joints. Some is now so thin a pipe cutter won't cut it. Sinks not scoured out often turn copper green. Gradually replacing with PEX.

Neighbor had to replace all the copper pipe in his house at about 10 years old. He used PEX, too.

I've heard it is slightly acid water, but I haven't checked.

Bruce

 

[RNeumann]

Copper doesn’t last like you think it should. I did plumbing repairs for years and fixed a lot of copper! The hardness or minerals in the water seemed to make things worse. It’s the turbulence and abrasiveness of the water/steam that is causing this.

I’d be letting the hospital know it’s time to budget a repipe! I guess the price of bandaids and Advil will need to go from $10 each to $15 each at your hospital.

 

[ultrarunner]

Yep... spoke with the original plumber today... he suggested budgeting for replacement... running parallel lines and making the cut overs on the weekend or after hours... it will be a job as I have already had to cut access holes just to get to some of it.

At the time... copper with brazed fittings was considered the best and cleanest for sterilizing instruments... have plenty of 1950 copper in the area with few issues... and when I have them it has always been at a fitting...

All of the medical gas lines are type K and so far so good...

 

[Tractor Seabee]

Yep... spoke with the original plumber today... he suggested budgeting for replacement... running parallel lines and making the cut overs on the weekend or after hours... it will be a job as I have already had to cut access holes just to get to some of it.

At the time... copper with brazed fittings was considered the best and cleanest for sterilizing instruments... have plenty of 1950 copper in the area with few issues... and when I have them it has always been at a fitting...

All of the medical gas lines are type K and so far so good...

Just think of all the copper that has been deposited on those sterile instruments. Is that medically a problem? Time to re-evaluate. During my Steamfitter career I never saw steam run through copper. How do you control the purity of your steam? Maybe the water/steam injected treatments don't match your conditions. What about your testing program? Low PH can wreck havoc with copper, brass, and steel. Is your plant automated or manned? An auto plant still has to have water chemistry manual checks, automated equipment gets out of calibration quickly w/o checking. Had one job where the owners maintenance crew (unlicensed) operated and maintained the boiler. Schd 40 pipe condensate lines started to pinhole, they replaced with copper, same thing, replaced with brass, same thing. Finally called us. First thing we called in a licensed boiler tech and a water treatment specialist. One month, all new piping, steam line (sched 80) were over half thickness, a water treatment system and a maintenance contract for treatment and they were back up and running. Turns out the system had leaks, make up water added every day, no chemistry tests, no treatment. Lucky the boiler was not severely injured but its life was shortened so the had a plan in place to replace it in the near future. They had a clean steam requirement so all new pipe was pickled steel, solvent cleaned, TIG welded, and fine strainers ahead of the condensate pumps. 5 years later we were still their service contractor of choice when I left the company.

Ron

 

[ultrarunner]

All great questions...

Boilers are 23 years old... one was re-tubed last year... others are original and opened/inspected annually.

Lots of make up water as all steam produced is consumed.

Water chemistry is tested monthly and treatment adjusted as needed.

Our water is very good for our region... in the valley the water causes problems all around for our sister hospitals...

In addition to the sterilizer steam feed line steam traps... each sterilizer has a manufacturers "Steam Conditioner" filter fitted with another small steam trap that runs to the floor drain under each machine... it sounds like a toilet flush when the machines are on standby... about every 8 to 10 minutes.

 

[dfkrug]

At the time... copper with brazed fittings was considered the best and cleanest for sterilizing
instruments...

Do you mean "silver-soldered"? I used that for liquid nitrogen copper lines back in the 70s. I don't
know about steam, but acidic liquids will eventually eat away your pipes, prob most at the
soldered joints. I imagine that TIG welded joints would last longer (no electrolysis), but that
would be a crazy amount of work.

I used corrugated stainless steel for all my gas lines....maybe there is a stainless solution
for steam? What do all the semiconductor factories around here use? I have some
really nice SS pipe scrap I have picked up from time-to-time.

 

[Tractor Seabee]

Do you mean "silver-soldered"? I used that for liquid nitrogen copper lines back in the 70s. I don't
know about steam, but acidic liquids will eventually eat away your pipes, prob most at the
soldered joints. I imagine that TIG welded joints would last longer (no electrolysis), but that
would be a crazy amount of work.

I used corrugated stainless steel for all my gas lines....maybe there is a stainless solution
for steam? What do all the semiconductor factories around here use? I have some
really nice SS pipe scrap I have picked up from time-to-time.

I worked as a pipe fitter in several chip plant in OR & WA. Those plants all had hot water for building heating systems, no steam boilers. Miles of SS tubing and pipe for process gasses which you do not want to know the contents as many are very dangerous. "Silver Solder" is one of those terms that is used interchangeably with "Silver Brazing". Soldering implies a low temp alloy that forms its bond through capillary attraction into the joint. Soldering has no inherent strength w/o having a close tolerance fit that prevents movement or some type mechanical fastener to keep the parts together first. Brazing is a high temp alloy (lower than the base metal) that can work same as soldering or into the joint with the capillary attraction into the joint surfaces. All depends on the type of joint. Brazing alloys have inherent strength in the material.

Ron

Ron

 

[dfkrug]

Miles of SS tubing and pipe for process gasses which you do not want to know the contents
as many are very dangerous.

Yeah we had a lot of cool chemicals in the semiconductor biz; my fave was an etchant called "piranha", a mixture of sulphuric
acid and hydrogen peroxide.

Anyway those miles of SS tubing and pipe can be picked up cheap, as salvage. Most of the semiconductor factories are
gone here in the "Silicon" Valley.

 

[Diggin It]

My house has the same problem, after about 40+ years. All leaks have been pinhole leaks between joints. Some is now so thin a pipe cutter won't cut it. Sinks not scoured out often turn copper green. Gradually replacing with PEX.

Neighbor had to replace all the copper pipe in his house at about 10 years old. He used PEX, too.

I've heard it is slightly acid water, but I haven't checked.

Bruce

Bunch of years ago when I still lived in a big city (good tasting water), I went in the basement one day and found water on the floor. Started looking around and found a 1/2 copper line leaking. Turned the supply off and went to check it closer. The pipe collapsed in my hand. It wasn't much more than copper foil. I can't remember now if I replaced it it with PVC or copper, but this house I'm in now has all PVC.