can I use pipe tape and thread sealant on hydraulic fittings?

[sawkiller]

If you still are having the leak and haven't found or got either the gasoila or the loctite curing sealant mentioned above (both work very well). Then you should look at a couple of things obviously you threads are not perfect or it would not be leaking. No offense just how it is and believe me there are no perfect threads but some are better than others.

Take it back apart and put a rag in the pipe and take a wire brush and clean up the threads and inspect them closely then pull out the rag. On the female threads to keep the system clean I would use a copper fitting brush and basicly unscrew all the tape and dope on the threads and once again inspect closely. Then in a pinch go to the hardware store and ask for teflon tape for gas lines it is usually a bright yellow color. It is a much thicker and heavier teflon or PTFE and if three wraps of that properly applied (if it all rolls up and balls when you put it together then pull it apart and wrap the other way) don't fix it then try getting a new piece of pipe!

 

[100 Watt]

Plumber here as well.

Let's not forget, "don't bite your finger nails"

Personally, I like TU-555 pipe dope.

 

[BlueRidgeMark]

Once again if it is standard pipe thread you need some sort of sealant

But then, if it's standard pipe thread, it doesn't belong on a hydraulic system in the first place!

 

[radroy92]

Formula-8

This stuff will work on tapered threads up to 10,000 psi and hydraulic fluids. +500 degrees F on hydraulic systems.

Fluoramics Inc.

Part # 4538K1 McMaster-Carr McMaster-Carr

Roy

 

[tanker]

But then, if it's standard pipe thread, it doesn't belong on a hydraulic system in the first place!

Funny,alot of cylinders and valves for hydraulic are NPT Scott

 

[MH49]

That is true for log splitters and old farm tractors and is fine for low pressures (Approximately 2500 psi and down.) However 'modern' equipiment uses O-ring boss, JIC and O-Ring face seal as others have noted. All these are much better for higher pressures than a connection designed primarily for water. Keep in mind that a heavy duty hydrostatic transmission will run up to 6500 psi and implement circuits can run up to 3600 psi and higher.

 

[radroy92]

PTFE locknut seals

Anybody ever use these??

Roy

 

[firewood guy]

Just say no to N.P.T. Thats for plumbers!!

Probably restating the obvious, but modern HYD systems don't use NPT fittings except.. maybe.. the return / suction side. Almost all MFGrs use STOR fittings ( straight thread O-ring), and some still use the old JIC 37 degree tapered-seat stuff. Not a good idea to use teflon anywhere it could be introduced into the hydraulic circuit. It voids medium and heavy duty const equipment warranties if they find it in the system when making a claim. This info comes from CAT and TEREX employees that are personal friends in the biz for lots of years. Get the best.. use STOR fittings.. that way you can index the hose/ fitting alignment anywhere you want it w/o fear of leaks or having to use sealants that have no business of being anywhere around a HYD system. Hope this helps.

 

[radroy92]

Stuck with NPT

Probably restating the obvious, but modern HYD systems don't use NPT fittings except.. maybe.. the return / suction side. Almost all MFGrs use STOR fittings ( straight thread O-ring), and some still use the old JIC 37 degree tapered-seat stuff. Not a good idea to use teflon anywhere it could be introduced into the hydraulic circuit. It voids medium and heavy duty const equipment warranties if they find it in the system when making a claim. This info comes from CAT and TEREX employees that are personal friends in the biz for lots of years. Get the best.. use STOR fittings.. that way you can index the hose/ fitting alignment anywhere you want it w/o fear of leaks or having to use sealants that have no business of being anywhere around a HYD system. Hope this helps.

Those fittings are great I agree but.... the old Miller cylinder ports are 3/4 NPT. So I have to use a fitting with pipe threads.

Roy

 

[firewood guy]

Those fittings are great I agree but.... the old Miller cylinder ports are 3/4 NPT. So I have to use a fitting with pipe threads.

Roy

There are adapters available to go from a NPT to a STOR. I would suggest using Loctite sleeve retainer sealant to make the leak-proof connection @ the NPT fittings. Have had great success w/ this in the past, providing you have the room for that extra 1" plus of adapter!! Good luck.. Mike P.S. Make sure you have ample cure-time for the Loctite @ good ambient temp before you put the unit back in service....

 

[firewood guy]

:agree2:

Gotta agree... Rectorseal products are some of the best! Never had a failed pressure test inspection in 20 years. Oh, also a GC and a plumber!!!

 

[Dimwitted redneck]

I am installing fittings on my splitter build.
the manual for the hyd valve does not recommend using pipe tape on the hydraulic fittings. I'm looking at pics of log splitters on this web site and I clearly see pipe tape. what's up with that?
would it be ok to use tape on the final few threads?
also, they recommend not using thread sealant with Teflon.
why is that?
thanks for your help,
topo

Hello All,
I have read the first few replies below........few are fact, most are misguided opinions. The one that stands out as the best response, or the mostly accurate response to your question, is from SAWKILLER (congrats, you win).
In my words: The JIC fitting has 2 sets of threads, on the tubing/hose side of the fitting, you have the JIC threads; which, typically should be installed dry, or "metal on metal". However, In some applications, the nut can have a tendency to vibrate loose, and allow the connection to leak. looking at the function of the individual "components" of the fitting, The angle on the end of the fitting, is one of the two parts that compose the "Sealing Surface", and this section of the fitting is intended to be installed, metal-on-metal.....end of conversation, no exceptions. Now, the thread section of the JIC portion of the fitting, is one of the two parts that has one function, and that is to "maintain or hold the seal". On this section, I will use the LOCTITE brand threadlocker (not to be confused with sealant). I have used the Loctite thread locker, to prevent the connection from becoming loose, due to vibration, many, many, many times, and have to date, experienced a 100% success rate.
Now, the other side of the fitting (with the exception of a JIC union, or JIC "T", etc...) can be a multitude of different types of threads, to include, but not limited too: NPT (National Pipe Taper), BSPP (British Standard - Parallel threads), BSPT (British Standard - Tapered threads), O-ring face seal, etc.... With the other side of your fitting being NPT, then YES, you should use a sealant, (i.e. Loctite sealant, paste sealant, tape sealant, etc...) because on NPT, the threads are creating the seal (my personnal, unproven, unfacted, OPINION is: the biggest advantage offered by the sealant is that it lubricates the mating surfaces of the threads, allowing the connection to be tightened further, in which decreases the area between the two surfaces (it's tapered) increasing the resistance to leaking). Now, if the other side of the fitting is BSPP, then NO you SHOULD NOT use a sealant.
Gotta go, so in summary,
- USE SEALANT ON thread to seal fittings (such as NPT). (THE THREADS CREATE THE SEAL OF THE CONNECTION)
- DO NOT USE SEALANT ON JIC SEALING SURFACE (ANGLE), BSPP, O-RING FACE SEAL, ETC (THREADS DO NOT MAKE UP THE SEAL OF THE CONNECTION)

sealant tape is not recommended, because if you are careless, or do not know any better, you can tape past the lead threads, or worse, over the end a bit.....the tape will shear and take a ride on the oil river to the next component and reak havac on tightly toleranced parts in motion (spool valves, pumps, proportional valves, etc...).

 

[turnkey4099]

If you are talking a standard national pipe thread joint then yes a good qaulity teflon tape and a good qaulity thread compound is in order. The reason the manufacturer says not to use it is they do not want it in their pump or valves causing damage. My sugestion is do not tape the first thread and this will eliminate the above problem. Also read the directions on the thread compound that you get and it will tell you what it is good for and how much pressure. Gasoila compound comes to mind and with it no tape required but still keep the first thread clean.

Exactly. I worked builting parts for agricultural sprayers. Lots of hydraulic pumps. Had failures traced to shreds of tape in the pumps.

 

[GVS]

I am installing fittings on my splitter build.
the manual for the hyd valve does not recommend using pipe tape on the hydraulic fittings. I'm looking at pics of log splitters on this web site and I clearly see pipe tape. what's up with that?
would it be ok to use tape on the final few threads?
also, they recommend not using thread sealant with Teflon.
why is that?
thanks for your help,
topo

You can use tape on pipe threads BUT don't over torque and as stated above don't start the tape on the first thread.When starting the tape go the OPPOSITE direction from tightening.No more than 2 wraps around.On flared fittings use no tape or dope of any kind!The 2 flares mating are what keeps it from leaking.

 

[Wow]

I'm replacing

You can use tape on pipe threads BUT don't over torque and as stated above don't start the tape on the first thread.When starting the tape go the OPPOSITE direction from tightening.No more than 2 wraps around.On flared fittings use no tape or dope of any kind!The 2 flares mati are what keeps it from leaking.

I'm replacing the Hydraulic cylinder on my Huskee 22 ton Splitter.
This thread had helped me a lot. I removed the Elbow on the high pressure end of the old cylinder very carefully checking for any signs of Pipe thread sealant. Where the Elbow entered the Cylinder there was a chalky substance in some threads but not near the end. Where the High Pressure line attached is the "0" ring seal BUT to my surprise there was residue on the threads but well back from the tip.
Before I remove the Control Valve off the old cylinder I'm considering marking it and counting the rounds to use as a rough guess giving me some Idea about what to expect.
The Hydraulic Filter on my Huskee Splitter is a Speedco 390601AO. The parts house crossed it to a Wix 51249. When I got home I ran the Specks and learned that Speedco actually makes that filter for Wix and it's a 10 micron. Thinking that I'd need 30 micron filteration I checked the Specks on the Speedco. I was expecting something near 30 micron AND, I learned that BOTH the Wix and Speedco are 10 micro. In fact the Wix 51249 IS actually the Speedco 390601AO under a different name.
Now that I have the correct filter all I needed was the correct pipe thread sealer. For that I bought Permatex High Heat Thread Sealant. Wish me luck with the new cylinder. It was scary cheap 219 bucks from the River AmZone plus free Shipping. These cylinders look like twin sisters. Black paint on the push rods right up to the Glad nut wiper seal. I think a paint chip is what caused the old seal to leak. IMHO painting a chrome actuator rod isn't smart. Good day.

 

[muddstopper]

I doubt Speedco makes any filters for anybody. Wix on the other hand makes filters for most everbody. Second, a 30micron filter has less filtering capacity than a 10micron. If you want a finer filter you would need to go to a 5 micron. A 1 or 2 micron filter will take the red out of transmission fluid,, as well as most of the special lubricating additives used when the oil is made.
Oring fittings and jic fitting use no thread sealants. With pipe threat, use a sealant made for hydraulics, not plumbers tape.

 

[dmb2613]

People that don't use tape or sealer on NPT fittings are fools and have leaks
David

 

[lone wolf]

If you are talking a standard national pipe thread joint then yes a good qaulity teflon tape and a good qaulity thread compound is in order. The reason the manufacturer says not to use it is they do not want it in their pump or valves causing damage. My sugestion is do not tape the first thread and this will eliminate the above problem. Also read the directions on the thread compound that you get and it will tell you what it is good for and how much pressure. Gasoila compound comes to mind and with it no tape required but still keep the first thread clean.

Can tape and the compound be used together?

 

[Wow]

I doubt Speedco makes any filters for anybody. Wix on the other hand makes filters for most everbody. Second, a 30micron filter has less filtering capacity than a 10micron. If you want a finer filter you would need to go to a 5 micron. A 1 or 2 micron filter will take the red out of transmission fluid,, as well as most of the special lubricating additives used when the oil is made.
Oring fittings and jic fitting use no thread sealants. With pipe threat, use a sealant made for hydraulics, not plumbers tape.

Well here is what I found after hours of searching. I'm not going to look for the site don't have time. Maybe I misinterpreted who made what but somewhere I read this.
Wix filters:
Speedco 51249 sold as Wix.
Huskee 51553 Sold as Wix.
Husee 33 micron
Speedco 10 micron.
My Stump Grinder came with an oil filter that has Speeedco 390601AO written on it
Info states 10 micron.
The Wix (Speedco) states 10 micron. Exactly the same and Wix may have made it or Jesus, all I know is what it said. In the meantime somewhere, sometime someone put that 10 micron filter on my Huskee. I bought it slightly used so there is no telling but my gut feeling is go back with what came off. The Specks of the Speedco (Wix ) 51248 match exactly. Could be that the previous owner put the Speedco on. The Wix that states Huskee 51553 has 33 micron. Maybe the 10 micron created the leak and i may be messing up going back with Speedco - Wix 51249. Thanks.

 

[lone wolf]

Well here is what I found after hours of searching. I'm not going to look for the site don't have time. Maybe I misinterpreted who made what but somewhere I read this.
Wix filters:
Speedco 51249 sold as Wix.
Huskee 51553 Sold as Wix.
Husee 33 micron
Speedco 10 micron.
My Stump Grinder came with an oil filter that has Speeedco 390601AO written on it
Info states 10 micron.
The Wix (Speedco) states 10 micron. Exactly the same and Wix may have made it or Jesus, all I know is what it said. In the meantime somewhere, sometime someone put that 10 micron filter on my Huskee. I bought it slightly used so there is no telling but my gut feeling is go back with what came off. The Specks of the Speedco (Wix ) 51248 match exactly. Could be that the previous owner put the Speedco on. The Wix that states Huskee 51553 has 33 micron. Maybe the 10 micron created the leak and i may be messing up going back with Speedco - Wix 51249. Thanks.