View Full Version : PEX fastener terms -compression ring, crimp,clamp...

10-23-2008, 01:05 PM
The terminology for the piece which is used to fasten the fitting to the tubing does not seem to be standardized amongst retailers. I'm confused by the non-standardized usages of the terms crimp and clamp; sometimes phrased as "crimp ring" and "clamp ring," as opposed to "compression ring."

Omitting the fitting that is inserted into an expanded tube which then shrinks back around it:

AFAIK there are:

1 COMPRESSION RINGS; made of copper, which use a unique tool and a gap gage to verify adequate compression. The ring is a solid band. Some are colored black to mark them as being for use with the obsolete polybutylene (PB) pipe.

2) CLAMPS, made of stainless steel, which use a different unique tool that ratchets until it is tight enough. See


3) Oetiker Stainless Steel Crimp Ring, which might use the same tool as 2 or not, I'm not sure. See:


Does "SSC" (stainless steel clamp) refer to just 2) or both 2) and 3) ???

I have also come across references to a fastener/tool where you have to "snip" a tab before using the tool to tighten it.

Using all 3 items (pipe, fitting, fastener) from one manufacturer is prudent, but since I have not decided which brand to use, I'd really like to see a table showing various manufacturers stuff, with the trade name they use, divided into the categories of fasteners.

Does anyone make plastic fittings usable with the clamp type fastener? Looks like Watts "Poly-Alloy" plastic fittings are only to be used with the Compression Rings. Their brass fittings can be used with either.

My acid water makes me want to go all plastic, but I think the skill level of the crimp fastener is easier to succeed with than the compression rings. And the tool is much cheaper.

10-23-2008, 01:45 PM
I'm only concerned with potable water plumbing, not radiant heat, so I will not include those parts and trade names.

tube: WaterPEX

Brass Insert Fitting, no special trade name
1) compression ring -- "CrimpRing"
2) clamp --"CinchClamp"

Plastic Insert Fitting "Poly-Alloy CrimpRing Fittings"
Fastener: usable only (?) with compression ring -- "CrimpRing"

ALSO have a quick connect design:
Plastic "Quick-Connect Series 35" fittings. Merely insert the pipe to the stop (no tightening of compression rings). Similar to SharkBite, which are metal.

1) copper, plain tubes with stubs, optionally valves included
2) The Quick-Connect line has pieces designed to assemble a manifold of any configuration


tube: Zurn PEX

Insert Fitting, brass -- QickSert 1
1) copper crimp rings (no special trade name, compression type)
2) stainless steel crimp rings (no special trade name, but are a CLAMP design)
3) QickClamp; uses a go/no go gage like compression rings. But one tool does all sizes.

Insert Fitting, plastic -- QickSert CR
Fastener: not stated in the catalog. All 3 fastener styles are listed within the brass fitting section. The rep on the phone says it can use all 3 of their fastener styles.

ALSO have a quick connect design:
Plastic "QickTite Fitting System" which uses a compression nut/ring/cone.

1) "QickPort" is plastic, various sizes and some modular features
2) copper manifolds - plain tubes with stubs

10-23-2008, 01:52 PM
Notes from a phone conversation:


FLAIR- IT FITTINGS all plastic, traditional plumbing compression ring style.

BESTPEX TUBING recommended for compression fittings (white flair-it fitting)

FLEXPEX TUBING recommended for crimp style fittings which includes the Oetiker clamp SSC

rep says poly alloy insert fittings can use copper compression rings or the SSC CLAMP by Oetiker

10-23-2008, 01:56 PM
From some phone calls tracking down divisions of bigger corporations:

website is h-a-s.com
a division of Hydro-Air Systems Inc .

manufacturer of:
Hydro-Flex -- PEX-AL-PEX tubing
Hydro Qual -- PEX tubing; designed for radiant heating and potable water
Hydro-Plumb -- PEX tubing; designed for potable water systems

master plumber mark
10-23-2008, 02:48 PM
It looks like you have done your homework,

Why worry about all of it....cause it is a hopeless cause.

none of this crap is standardized and its the wild west out there.....

So if the Expert at Lowes or Home Depot says its ok and is compatable with
what you want to do , you should listen to the experts...

Of course Zurn has a lawsuit going on right now....

and when it all falls apart in a few years it will be some one
elses problems.....

its gonna be the plumbers problem.......

10-23-2008, 06:57 PM
The problem with buying at a Box is that you don't know if you are mixing & matching. That's the reason for creating this list.

Zurn's problems are with brass fittings, which I am not going to use.

10-24-2008, 06:04 AM
Pig slops gonna run amok when the big boxes start selling PEX and PEX fittings. Smirking as I'm typing this. Gonna need a machete to get through crawls in the future.

10-25-2008, 09:01 PM
I was many years ago a plumber in Terry's neck of the woods in King and Pierce Counties in Washington. We replaced many poly butyl installations with copper. My boss contstantly preached the virtues of sch L copper and that nothing else would ever be acceptable for residential/small commercial potable water supplies.

For the past 5 years, he has largely switched over to PEX. I am building my own residence and he has almost talked me into installing an all-home-run PEX system with a single manifold in the laundry room. His pro-pex position stems from no fittings in the walls and no bursting when pipes freeze.

I was looking at the Zurn compression ring fittings using the proprietary crimping tool with the go/no-go gage. Am I heading down a path of future destruction?

AcidWater, how are you going to install a workable system without any brass fittings? I know you can use copper for some fixtures, but how would you connect the inlet side of your shower valves if you do not use brass? But since acid is an issue, you cannot use copper anyway. How are you going to transition to your fixtures? Are you going to use compression angle stops with an insert directly on the PEX stubouts?

You all have piqued my curiosity. Better now than later...

10-26-2008, 07:58 AM
One thing you may need to realize is that replacing all your pipes with PEX does not eliminate the need to treat your water. The acid water will still cause harm to the fixtures, valves, brass connectors used etc.

I would strongly consider installing an acid neutralizer which may also bring with it the need for softening. The PEX is merely a means of replacing the pipes which have been ruined by the acid water.

10-26-2008, 08:25 PM
Not worried about taps, they are really thick and easy to replace if necessary. PEX to the tap hookup end.

It took 40 years to eat thru the pipes. Investigating the costs & PIA factor of acid neutralizers is something I might get around to doing when I have some time & energy.

10-26-2008, 09:49 PM
Actually it may have been a recent change,,,
Acid water with a small PH change like down to mid 6's can eat through pipes in no time at all...

Sometimes your water which was fine for years can change into a foul pipe eating brew...

10-26-2008, 10:15 PM
So the Search function will be useful -- hydro-pex seems to usually be spelled HydroPEX.

11-16-2012, 04:49 PM
Try just dumping 10 pounds of baking soda in your well.
Run a hose down into the well and circulate for an hour or so.

The PEX industry i very highly regulated and I know of no incompatibilities with the different manufacturers.
Therefore, the fittings and connectors are inherently universal (in theory).

Compression rings are cheaper and don't have the ugly crimp, but need a larger tool which is increasingly difficult to use in even slightly small places.
Crimp rings are stainless steel, which won't corrode in damp locations like copper compression rings.
Crimp rings are much easier to remove.

11-17-2012, 07:21 AM
If you do not use brass fittings, then you use the plastic ones, and they have an even smaller opening, because of their thicker walls, than the brass ones. Compound that with the smaller i.d. of PEX initially, and you see IMMENSE flow resistance. Your #2 and #3 are the same. I call them "cinch" connectors because you cinch them closed with the tool. The only reason for using a ratchet tool with them is if you have limited space to squeeze the handles, or you need additional mechanical advantage. I have not had that happen yet.