Hello,
Does it matter which way a plastic ferrule used in a compression fitting faces; that is, should the wider end face towards or away from the nut, or doesn't it matter?
Thanks,
Bill
Compression Fittings
Originally Posted by bsquared18
Hello,
Does it matter which way a plastic ferrule used in a compression fitting faces; that is, should the wider end face towards or away from the nut, or doesn't it matter?
Thanks,
Bill
Yes, it matters. The wider face goes towards the nut.
Thanks, Furd.
Pulpo, I'm afraid your link wasn't helpful because it focuses on metal ferrules, which, as far as I can tell, are symmetrical rather than having one end wider than the other.
Interesting that on that link it says you can use metal ferrules with plastic, whereas a plumbing expert at the local hardware store and a forum writer I saw online both said emphatically that metal ferrules tend to cut into a plastic line, eventually causing a leak in many cases.
That's why I'm going with plastic ferrules.
Bill
As long as you use a metal ferrule inside of the plastic..you CAN use a metal ring...but it depends (IMO) on whether its soft or hard tubing. You have to tighten it til it's snug..then apply pressure and check for leaks. You can't just torque it to the max and call it good. With swamp coolers that use a sort of hard plastic tubing, I've found metal rings (using the ferrule) are better, with soft lines I always use plastic rings and a ferrule.
Notice in the tips in the link..it does say a plastic ring is better than a metal one.
All depends on the application...which we don't know what yours is. Hopefully not an icemaker? Never ever use plastic for an icemaker.
GungGuy,
It's probably not important, but I'm a writer and former English instructor, so words matter to me.
Correct me if I'm wrong (which I often am), but I thought that a ferrule was the metal ring, and the piece that goes inside the tubing was called simply an insert.
One online dictionary has the following definition for ferrule:
1. A metal ring or cap placed around a pole or shaft for reinforcement or to prevent splitting.
2. A bushing used to secure a pipe joint.
(On a Britsh YouTube video, that ring is called an olive. On another video, it is called a pearl ring.)
Anyhow, to be on the safe side, I'm going with the plastic ring/ferrule and the insert. I was told that the insert is intended to keep the tube from collapsing, not to keep the ferrule from cutting into the tube.
Bill
Ahh...yer probably right....it just seems like I always heard them called ferrules when I first started DIY stuff.
Check the last part of my prior post...I was called away while editing..
Whats the usage of the fitting?
It's for the line from the cold-water pipe to an under sink filter and for the attachment between the line coming out of the filter and the separate faucet for the filtered water. The filter itself uses push-in quick-connects, which seem to be working fine.
I had used metal ferrules before learning about the potential problem. Since I'm adding a flow-meter to the line anyway to tell me when to change the filter, I decided I might as well remove the metal ferrules, check for any line damage, and replace them with plastic ones.
Bill
As someone that has used literally thousands of compression fittings I will state emphatically that you do NOT want to use a metal ferrule on a plastic tube unless you have no other choice AND you can replace it soon with the proper plastic ferrule. This especially true if you are using the common double-ended brass ferrules available from any big box or hardware store.
Thanks, Furd.
Am I correct that I can use the same brass fittings and metal inserts, as long as I replace the ferrules?
Also, I assume that if a line was damaged at all by the metal ferrule, I should snip off that part first. Correct?
Bill
I would advise you to not mix and match different materials and different manufacturers. Different manufacturers may use different angles on the ferrules. While it might work there is no guarantee.
I suggest using push-in fittings on both ends of the tubing or replacing the push-in fittings on the water filter.
Absolutely, if the tubing has been damaged by the ferrule you need to cut off the damaged area.
Tags: does, matter, plastic, ferrule, faces, metal ferrules, with plastic, metal ferrule, metal ring, plastic ferrule
