Copper Riser Anchors

Have you considered checking the alloy content of the copper that failed compared to that which has not?

We have checked the alloy content of the failed anchors, we are using the same copper for each anchor. The main problem is the field fabrication quality is not consistent, each tab needs to be bang on even to distribute the load, if they're not even, one by one each tab will fail.

You're right, the current methodology does sound pretty Mickey Mouse.

Have you checked with any plumbing supply houses or manufacturers as to whether there is a piece designed to do this?

If it doesn't exist, one thought that comes to mind would be to use adaptor fittings, the flared pieces that adapt whatever your pipe size is to the next size up in diameter.

Use 2 fittings, big end to big end, with a gap in between to accomodate the clamp. You could still use ≈6" pieces of pipe as spacers between the small ends if there is any concern as to strength.

You could fabricate pieces that are more reliable than what you are using now by flaring the ends of the 6" sections rather than notching and bending. This may not be a field fabrication, but probably cheaper than fittings, even having them made for you.

Some solder built up between the pipe and the inside of the flare (or folded tab) would likely help prevent either from folding back.

If you want to discuss this further, let me know. I'm local, and this is what I do (mechanical/product design).

grkadisch@rogers.com

Copper coated riser clamps. Use one at every floor. Should be available at local plumbing dist.

Where do you install expansion joints?

How long of continous vertical pipe and how many branches?(floors) Also highest and lowest temp seen on the pipe? The greater the delta of the pipe the more it grows and shrinks.

It's a 40 storey condo, fan coil riser, 2 pipe system. Approx 50F in summer, 160F in winter. The design calls for 4 anchor points with expansion compensators in between.

You could cut a ring from a sheet of copper and attach to tube instead of the bent tabs...

Go with the engineers design. Also if the expansion joints are installed, were they installed properly? Check your local codes and the installation info that came with the expansion joints. Info should be with submittals or O&Ms.

We have followed the engineers design and the expansion compensators are installed in the correct location, we even had the manufacturer on-site to confirm this. The problem is the current method of anchoring the risers as described previously is not "engineered" to handle specific loads, it's more or less trial and error and is highly dependant on quality of workmanship. We are using a bellows type expansion compensator as opposed to the traditional loop type expansion joint. These compensators create substantially more pressure thrust than a traditional loop. I have design in mind that is basically a copper or brass coupling that is more or less shaped like a spool fitting that the riser clamp would be fastened between and the riser clamp welded to angle iron imbedded in the slab. I'm thinking there has to be something like this on the market already somewhere.

Should work

Hi, hope you are still around...

I too live in a large condo hi rise in toronto.

We may be having similar issues. We hired a consulting engineering firm to look into failures of loop type expansion joints. As a result, we are replacing many components of out 2 pipe HVAC.

When we went to tender, at least one of the contractor requested the riser pipe anchors be replaced. From your experience that sounds like a good idea, but the recommendation did not come from the consultant but the contractor.

Could you please explain what you used to replace the original anchors? also did you have any issues with the Tee's that lead to and from the fan coils. I hear they flex and eventually fail.

I have low confidence in the consultant since he didn't put anchors in the bid spec, but think the contractors know what they are doing.

I think, we will peek in the walls soon, have a two part bracket clamp, which may or may not have a rubber insert. The suspicion is that the rubber deteriorates and the riser slips.

The building is 30 years old and 30 stories high.

Hope this reaches you

Thanks

Barry