seals , chevron type, paulson cylinder

ejensen

Well-known Member
I replaced the seals in one of the
lift cylinders on my Paulson loader. Cylinders are hydraulic up gravity down. 4 chevron type seals are used. 4 5/16. bolts are used to hold the end flange rot the cylinder. I just pulled the bolts up snug. Looks like this type sealing on a hydraulic cylinder Has to be checked and tightened as necessary. Is this correct? Reminds med of the stuffing box on the propeller shaft on a boat. You tighten but not over tighten as it is possible to lock the shaft
a153770.jpg
 
Bob,
Than you for the information. I really didn't know just proceeded in the way I have worked on other equipment boat shafts, pumps with turning shafts and packing
 
(quoted from post at 00:20:13 04/12/14) I replaced the seals in one of the
lift cylinders on my Paulson loader. Cylinders are hydraulic up gravity down. 4 chevron type seals are used. 4 5/16. bolts are used to hold the end flange rot the cylinder. I just pulled the bolts up snug. Looks like this type sealing on a hydraulic cylinder Has to be checked and tightened as necessary. Is this correct? Reminds med of the stuffing box on the propeller shaft on a boat. You tighten but not over tighten as it is possible to lock the shaft
a153770.jpg

I don't see any gland "lock nut" type of arrangement on that cylinder. I would think you adjust the number of packing rings until you reach the point where you can fully tighten the bolts shimming as required and get a seal without binding the rod.

TOH
 
There were 4 chevron seals in the cylinder
have a parts diagram for the cylinder which shows
4 seals. Replaced with 4 new seals
 
Cylinder would not retract. Seals were deformed and were locking the cylinder. Works good now. Cylinder was very difficult to get apart.Used a pipe vice, heat, large pipe wrench and hammer
 
Hokie, the 4 bolts perform the same function as a "gland nut.

NOT sure what he has , but it looks very similar to the cylinders on the old Johnson loaders I grew up around. Every now and then we would have to snug the 4 bolts up a bit when they started weeping a little.
 
(quoted from post at 23:31:59 04/12/14) Hokie, the 4 bolts perform the same function as a "gland nut.

NOT sure what he has , but it looks very similar to the cylinders on the old Johnson loaders I grew up around. Every now and then we would have to snug the 4 bolts up a bit when they started weeping a little.

I am suggesting shims on the bolts to allow you to properly tension them without crushing the packing. With no tension on the bolts they are prone to loosening and when that happens the gland leaks. I think you will find that properly torquing the gland bolts will significantly reduce the frequency with which you need to "snug them up".

TOH

[b:301d71d7f7][u:301d71d7f7]Adjustable Gland Installation Guide from Garlock[/u:301d71d7f7][/b:301d71d7f7]

ChevronPacking.jpg
 
TOH,
I think the seals were binding the shaft. Problem started when the loader would not lower
When replacing the seals and tightening the bolts
around the seal retainer noticed it was possible
to tighten too much which would prevent movement
of the shaft.
 
(quoted from post at 08:41:06 04/13/14) TOH,
I think the seals were binding the shaft. Problem started when the loader would not lower
When replacing the seals and tightening the bolts
around the seal retainer noticed it was possible
to tighten too much which would prevent movement
of the shaft.

I understand the binding issue. Chevron packing uses the internal hydraulic pressure to effect the seal. You don't need to compress them much at all to get a high pressure seal. You just need to compress them enough to produce uniform contact around the rod and that won't be enough to properly tension the cap screws. Without the proper tension (torque) the bolts are going to keep loosening up in use. If you put shims on the bolts you will be able to torque them nice and tight without crushing the packing. Here is a suggestion:
  • [*:de3f1841f6]Use a feeler gauge to measure the clearance between the cap and gland as you currently have it[*:de3f1841f6]Remove the cap and and place enough shim washers on the bolts to make up that clearance[*:de3f1841f6]Reinstall the cap.and evenly torque the bolts to the value recommended for the bolt grade and thread size[/list:eek::de3f1841f6]The rod won't bind, the gland won't leak, and the bolts won't work loose in service.

    TOH
 
TOH
Outstanding information , thank you. I am curious,
Knowledge you have only comes from years of experience or some type of specialty work experience such as a design hydraulic engineer. Maybe both. Would you mind sharing how you acquired the knowledge you have?
Knowledge I have regarding repairing equipment had come through 60 years of learning by doing and and learning from other people
such as yourself
 
(quoted from post at 09:32:10 04/13/14) TOH
Outstanding information , thank you. I am curious,
Knowledge you have only comes from years of experience or some type of specialty work experience such as a design hydraulic engineer. Maybe both. Would you mind sharing how you acquired the knowledge you have?
Knowledge I have regarding repairing equipment had come through 60 years of learning by doing and and learning from other people
such as yourself

My Professional Resume:

My formal college education started with a brief two year stint in the Physics curriculum at VPI before I switched my major to Mathematics in order to get a job as an intern at the David Taylor Naval Ship Research and Development Center in Bethesda MD. My focus as a math major was on topics in abstract algebra, topology, and numerical methods and I graduated with a BS in 1973. After graduation I worked at DTNSRDC for another 15 years and I did a bit of post graduate work in computer science but it was the roaring 70's and I liked to party more than study so I never completed any advanced degrees. :shock:

My work at DTNSRDC exposed me to a number of engineering disciplines - principally ship hull and piping design, submarine and surface ship silencing, numerical hydromechanics, super computing, and the birth of the Internet. I was a "software engineer" working with naval architects and engineers of all types, a world class collection of mathematicians, and the hands on manufacturing folks at the Norfolk News and Groton shipyards. Digital computing was just getting off the ground and we had the best machines money could buy. We were designing high performance computer systems and networks and developing computer codes to automate the design, manufactuure, and performance analysis of submarines and surface war ships. I learned a little bit about a whole lot of stuff far removed from my specialty area of mathematics and computer science. All I had to do to learn was listen.

The next 25 years were spent at the National Bureau of Standards (now NIST) where I did some Internet development work, managed their Experimental Computer Facilitiity, and participated in the development of various IT technical standards. designed and coded some reference implementations for those standards. I also worked on a couple of software conformance testing projects and did a certification test design and testing of some DHS computer forensic software. I ended my career working on a two year long medical imaging project that took me into the previously unknown world of bio-chemistry. Again - all I had to do was listen and learn.

So I am a 'quick learner" and reasonably handy with math, a pretty good programmer with modest experience and expertise in operating systems and networking internals. I know just a little bit about a whole lot of other technical stuff, I am a voracious reader, I like to get my hands dirty doing creative things, and my goal is to still be learning and/or creating something new the day I go to my grave.

In summary - a jack of many trades - master of none

TOH
 
TOH ,

S very impressive work [email protected] you very much. My work experience for 34 years
was as a teacher and vice principal in several middle schools. Received a BA in education from Western Wa. State University and MA degree from Seattle Pacific
I enjoy fixing up older farm tractors.I prefer ones with 3 point
 
i hate taking large cyls apart. i usually run them down to the hyds shp where they are better suited with a large heavy table.
 
Soundguy,

I was able to reseal one of the main lift cylinders.
Have the bucket cylinders apart now. I'll be going to skagit hydraulics tomorrow, want to get an estimate for them to reseal the bucket cylinders.
 
Soundguy.

Skagit Hydraulics gave me an estimate of 1hr per cylinder plus parts. $85/hr
I left the cylinders with thrm
I had the cylinders disassembled
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top