Pressing Or Pushing In The New Year
Julius Ballanco, PE
At last year's ISH North America show in Boston, I noticed the buzz around three booths. These three booths equally intrigued me. The booths were promoting the latest technology in joining copper tubing.
Nibco and Viega were promoting press fittings. While press fittings are not new, what is new is the introduction of press fittings by Nibco. It had a major roll-out of its press fitting line, which includes fittings from 1/2 inch through 4 inches. At the same time, Viega was introducing its new line of press fittings.
The other booth with the buzz was the joint venture between Nibco and Victaulic, a new company called NVent. NVent will be producing push-fit fittings for copper tubing.
Of course, when I went by the Ridgid booth, it was heavily promoting its tool for joining press fittings. I especially liked the new smaller, less expensive tool for pressing fittings 1/2 inch through 1 1/4 inches.
The Nibco press fittings looked very similar to the Viega press fittings. The O-ring is located in the middle of the joint socket. It also has a similar EPDM O-ring for sealing the joint. Nibco plans to introduce its press fittings the end of the first quarter of this year. That means within the next month or two.
Of course, I asked about the tool. I knew the standard response was going to be that there are separate jaws for each manufacturer's fittings. The real question was, will the tool and jaws work on both fitting systems? Officially no, unofficially, well, you void the warranty if you don't use the correct jaws, so why even worry about the unofficial response?
The tool and jaws for the Nibco fittings will be manufactured by Ridge Tool Co. It also makes the tool and jaws for the Viega fittings. Each manufacturer will add a mark to the jaws that shows up on the fittings. This will indicate if the proper jaws are used.
Nibco will include a full line of ball valves for its press fitting system. It emphasized that the ball valves will have union connections on each end to facilitate repair or replacement.
The Viega booth introduced its new gas press fitting system, ball valves and leakage path fittings. The gas fittings have a different O-ring - yellow in color, plus a yellow mark for the inspector to identify that the correct fittings were installed.
The leakage path fitting was a new and interesting fitting for water and hydronic systems. If the press joint is not pressed (with the tool), the fitting will leak during testing. This new design was in response to some contractors that claimed the fittings were pushed together, and the hangers and O-rings did such a wonderful job that the fittings passed the water pressure test. However, after a period of time, or perhaps higher pressure, the fittings would blow apart and leak. The leakage path will immediately uncover an unpressed joint and avoid future problems for the contractor. The ball valves exhibited were standard-type ball valves with press-fitting ends. They ranged in size from 1/2 inch through 2 inches.
You DecideThe NVent fitting system takes on a different approach. Rather than requiring a tool, the push-fit fitting simply requires you to push the fittings together.
The first thing I noticed about the push-fit fittings was that they were the same wall thickness as wrought-solder fittings. Press fittings have a much heavier wall. As it turns out, the fittings are standard wrought fittings that are finished off with an enlarged end. The enlarged end accommodates a gasket and stainless-steel grabber ring.
Two of the major concerns with the push-fit fittings are the proper end preparation and the insertion depth. NVent requires the outside end of the pipe to be chamfered with a tool they supply. The beauty of the tool is that it marks the tubing at the specific distance that it must be inserted into the fitting.
If you don't chamfer the tubing, you risk damaging the gasket. Since the gasket is making the seal, you don't want to damage the surface. If you fail to fully insert the tubing, the joint could eventually leak. Hence, the marking clearly identifies the distance you have to push the tubing into the fitting.
Once the fitting is pushed onto the tubing, it will not come off. Like press fittings, you cannot remove and reuse the fittings.
I did notice that it took some oomph to push the tubing into the fitting. Once joined, the fitting can rotate; however, it is not that easy to rotate. You need to put a little muscle into rotating the tubing in the fitting. Of course, on longer lengths of tubing, the torque will allow the fitting to rotate more easily. Hence, you need to properly support the tubing as required by code to prevent inadvertent movement of the tubing after installation.
The push-fit is only being introduced in smaller diameters - 1/2 inch through 2 inches. These fittings also will reach the market the end of the first quarter of this year.
Many have asked me if I think push-fit copper fittings will catch on. I don't know; that is up to you. Some push-fit fittings for other piping materials are used on a regular basis. Others never caught on with the plumbing industry. I would encourage all of you to investigate both push-fit and press-fit, if you have not already done so.
The introduction of these new copper-joining methods has validated that the industry is going in a new direction for joining copper tubing. The future is not with soldered fittings; it is with these faster, more efficient joining methods.
I don't think soldering will ever disappear from the plumbing profession. But, it may go the way of lead and oakum joints for cast-iron.
The key will always be the cost of installation. These new fittings are more expensive than solder fittings, but the labor savings more than makes up for the cost of the fittings.
Who knows, in 10 years, your torches may be sitting alongside the lead pot in your shop. I wouldn't be surprised.