OK Old Timers! I am too young for this crap! Got four cylinders with rope style packing in the gland, was leaking profusely and shamelessly! Tell me should I continue on with this, or order to make a new gland with contemporary seals in the groove! And how do I go about calculating diameter of the packing?! It’s not so much packing it’s self as another press in style seal inside of the packing tightening nut ( whatever you call that thing). I don’t like press in seals in cylinder glands! I like in groove seals. Moreover one of that is already popped out of its place on one of the cylinders! So what say you?! Leave it like it is or make new glands?!?!
What nappy cheaper quicker and easier to find and off the shelf cylinder was similar dimensions with modern seals. Just asking
Can’t do cheap and low quality! This crane have big job coming up in few months, owner specifically asked to make sure it will be running smoothly, will be some hired help depending on it! But!!! Cheap and high quality is always welcome around here!!!
Cheap and high quality......two things that are never in the same place at the same time.....
Well that is old school, old technology, but hell of high quality! I love how gland is separate from the cap! First it’s a lot easier to screw and unscrew, second you not tuning outside O-ring with a gland, you just slide gland in once, tighten the cap on top of it, and secure the cap with set screw with a BRASS BUNG ( so the set screw do not mess up the threads on barrel)!
We always called these Chevron seals. They can be order from seal suppliers.
You can also use a poly-pack or quad seal in there. You can make spacers in the seal chamber that hold the ring in place. We used to lots of them that way back in the late seventies. Actually, the chevron packing works real well also if you can get the rings. Check a local hydraulic shop for a source. I'm sure its an old machine and what is in there lasted this long.
Looks like the adjustable V packing to me. As said above, you can get new ones from most seal suppliers. Did you try to tighten the internal gland? The seal don’t look too bad from the picture. They usually can be tightened to stop rod leaks until the gland bottoms out. You also have to make sure you don’t overtighten the gland as it will burn/scar up the rod over time.
Thanks John! Gonna talk to local cylinder rebuild shop about options, they have their own machines and manufacture stuff in the house! Just wanted to know any pros about leaving it like it is!
The tightening nut was bottomed out! The outside O-ring on the gland was blown. This cylinder was the worst out of four. I like that you can periodically tighten the packing, just not sure the practicality of it, and like I said I really don’t like drive in seal on reciprocating rod!
Did this type of seal came with chevron style piston seal? I never actually worked with chevron seals before, only saw them on pictures and videos. But piston is a three peace with massive brass wear ring or I would say “slider guide” ( I will post pictures later ) in the middle of two opposing piston halves. Which kinda looks like was designed to accept sets of those chevron seals. Right now it has really thick loaded u cups in them. And the rope is one piece spiral, and not individual rings!
Anyone has formula how to select rope diameter by the size of the clearance?
I'm not sure what "rope" your talking about. A Pic maybe once it is out? Its not uncommon that people stuff something foreign at the top of the packing to gain more compression avoiding replacement of the packing. Normal ones I see will have a press cup on the top that is usually solid and made of plastic. I puledl a gland out in the past that someone had made a compression piece out of leather.
Those would be piston cups. Back in the day you would buy the cup and have to have the hole size for the piston piece pressed out of the center. You should be able to buy those cups also.
Well! Stupid me !!! You right! I was hurried up to another machine ( #4 winch on Ascom stopped working) and didn’t have time to remove all of it, just pulled the one on very end that actually got extruded between the gland and the rod! After being done with travel lift I was tired and went home. The one I pulled started unwinding, and that’s why I thought it was a packing like the one on the pump or old school rear main bearing on older engines!
You will want to check the support bushing inside that gland assembly as well, as those wear will allow the cylinder rod to sag against the packing and offset it in the bore, will hold awhile as replace it but over time will just return to leaking.
That’s what I am sitting and thinking about, there is a reason why that last one got extruded!
But on the other hand, the press cup made out of bronze and acts as slide bearing and sits there pretty tight. And there’s no pressure from that end beside press cup, so I think last v seal got extruded because of over tightening. Isn’t the last one on the barrel end supposed to be some kind of a pressure ring with square bottom, and just another V seal?!
That drive in seal is the dirt wiper, and is still the same design today. It doesn't hold oil, it prevents dirt and water entry to the chevron seals. If it's under pressure, the chevron seals are passing oil.
The big question here is how are the rods. Any blemishes in the chrome will tear up any type of seal put i there. Get new chevron seals mae sure the rods are i good shape ad put it back together. It will outlast us both.
Eah! I figured that! About the design - on today’s stuff wiper is usually “in groove” and sometimes require special folding tool to put in.
Rods have very little putting, but I think staying with chevrons will be better for that, then a single lip seal! It might “sweat” a little but for machine which was made in 50-60s it’s no biggie!
The dirt wiper on every cylinder I've touched has been drive in, from the outside. You're thinking of the U cup seal, which is the rod oil seal. From here https://www.flowcontrolnetwork.com/hydraulic-cylinder-seal-basics-design/
The very previous, right before this one I’ve touched!!! Took a picture of pitting inside the seal groove ( first is a wiper groove), to show it to the owner. Second picture is proof that I was right, it’s started seeping very next day! Even got and air bubble, although beside the pitting it had brand new rod machined that machine shop swore on everything holy to them, that that’s a crome plated rod! But you could have taken a fingernail, run it along the rod, and all the cats in one mile radius would pounce on top of your hand . Also they machined the coned shoulder where piston butts up to rod! And I swear, it is almost seven years since I moved from PNW to Gulf Coast - but the way people do things down here, and then look you innocently in the eyes and say “it’s fine, my Pa and Grandpa did it this way” - makes you wanna bang your head on concrete wall and roar at the top of you lungs!!! And when they crimp you brand new hose, they don’t clean them, and don’t plug them, and freshly rebuild cylinders, rotary manifolds, helical rotary actuators, delivered to you rolling around in the trash, on the back of the pick up truck, under open sky, without single plug ( even piece of rag ) in any port! And I remember seeing the whole Ultra Clean set up on the back wall of that shop all covered in black rubber dust! Rant is over!!!
And BTW I’m not cylinder guy! I’m more diagnostics guy! So forgive me for not knowing a lot about cylinders!!!
Chevron seals need to "sweat" a little. If not they dry out and get extruded. When you assemble one, soak the seal rings in oil before installing them, tighten the packing nut just past snug and stroke the cylinder a few times and watch the leakage, adjusting a bit at a time. Never choke it off completely, that will burn them out. That is the real truth with chevrons. They HAVE to leak a bit.
Run a thin film of lock tight around the wiper seal before you install it. I use bearing retaining compound. Helps to hold them in and will seal a bit of pitting.
Thank you! Thank you very much!
Thank you sir! I will do that!
I actually like 518 flange sealant, that stuff holds good. again, just a thin film.
Thanks!!!
Agreed that wiper seals need some form of retaining compound on them to keep them in place. In extremis I've seen the head of the cylinder drilled and tapped for something like 1/8" or 3/16" screws with large thick washers on them to guarantee that the wiper seal won't move. In fact some of the larger cylinders I've been around were designed that way.
Gland Packing even in the steam industry seeps, that keeps it moistened and lubricated so will slip not drag, a little wet is not a bad thing.
Did you actually mean it like that or do I just have a dirty mind.?
Thanks everybody!!! I wish everyone nice Labor Day weekend. I will be working Monday, baby sitting travel lifts and other equipment. We expect whole lot of work because of hurricane! Not sure though! Weather people constantly changing its path!
Good luck weathering the storm! Stay safe!!
518 is like Dave's hot sauce, I put that **** on everything
There are Other instances I am well and Dirty mindedly aware!!!! Kind of like Flat Washers and Sex, from a OLD man years ago: ALWAYS Face Up(the rounded edges of a Washer!) unless Greek then some can be Face Down!!!(IE Male!) And YES He was a Greek, his other favorite was Nothing better than a Fine young Woman, other than a Fair Young Boy. ICKY but was stated!!