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Do Zerk fittings have pressure ratings?

Rubycon

Rubycon

Madame President
A tapped 1/8" NPT fitting in a well at 6-10k psig. Fluid on high side would be equivalent of 90 weight gearbox oil but synthetic.
 
I'm positive they do, but I couldn't tell you what. I've seen so many blow out before over the littlest of pressure and I've seen others stand up to hell.
 
Rubycon said:
Drink your Ovaltine but not from the tap! 8,000 psi will rip your lips off! 😉



Contamination?
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Could of been, but when installing or replacing them I tried to keep the site as clean as I could. Don't need particulates etc getting down into bearings and what not. I tried looking up some pressure ratings and I haven't found any. It's been a few years since I've worked aroudn them though.
 
Actually Rubycon now that I think about it, it could of been contamination over the course of it's life that caused them to blow out. I still haven't found any pressure ratings though.
 
Ok I did a little research and I found some 1/8" NPT, 30degree, fitting rated up to 3k psi as leak proof. I saw others that were rated around 6k psi.
 
Typical high pressure lever guns are rated at 15,000 PSI.
All the track drive construction equipment I have used employs a grease cylinder with a standard zerk to adjust the tracks.
 
Evadman said:
My pneumatic one is rated at 10k psi, the run of the mill ones are rated at 6k psi.
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With the hose blocked off (using a 1/8" coupling or nipple depending on your gauge) what kind of pressure would you see while pumping it hard?
 
Rubycon said:
With the hose blocked off (using a 1/8" coupling or nipple depending on your gauge) what kind of pressure would you see while pumping it hard?
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Geez I like it when you talk dirty...😛

Quality grease guns have a built-in pressure by-pass so they don't overpressure.

It's easy as hell to blow seals (no, it's just ice cream) by putting to much pressure into the cavity with a grease gun. (grease guns can put out up to 15,000 psi while seals are usually good for up to 500 psi...the extra pressure may be required to force the grease through hoses and into tight bearings. (bearings that have a load against them may be nearly impossible to lubricate with a "normal" grease gun)
 
BoomerD said:
Geez I like it when you talk dirty...😛

It's easy as hell to blow seals (no, it's just ice cream) by putting to much pressure into the cavity with a grease gun.

the extra pressure may be required to force the grease through hoses and into tight bearings.

(bearings that have a load against them may be nearly impossible to lubricate with a "normal" grease gun)
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:hmm:
 
This is like the first time I've ever seen someone bring up this subject online. Pretty awesome there are other people on here that actually know what a zerk fitting is.
 
I've known what they are (imagine, they used to be on CARS!), but had no clue what the ratings were.

Auto manufacturers stopped putting them on in favor for sealed bearings. Anecdotally speaking, sealed bearings don't last as long as a maintained greasable one. However since nobody ever greased them, manufactures save warranty claim money by putting sealed ones that last as long as the warranty period. For every one person bitching that they should put greasable joints on there are 100 that never would've touched it anyways, and would've bitched when it broke because of it.
 
The overpressure mechanism (aka relief valve) is built into the pump I presume?

Oh and if you're aren't foaming you're not pumping hard enough! 😛

Oh and three words: pillow block bearing!

BoomerD said:
Geez I like it when you talk dirty...😛

Quality grease guns have a built-in pressure by-pass so they don't overpressure.

It's easy as hell to blow seals (no, it's just ice cream) by putting to much pressure into the cavity with a grease gun. (grease guns can put out up to 15,000 psi while seals are usually good for up to 500 psi...the extra pressure may be required to force the grease through hoses and into tight bearings. (bearings that have a load against them may be nearly impossible to lubricate with a "normal" grease gun)
Click to expand...
 
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Rubycon said:
Anyone put a gauge on a grease gun to see how much pressure can be developed?
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Yes, we've hit over 20,000 with some electric ones. hand levers are usually 10-15k, depending on model/brand and grease used.

Also, isn't "Zerk" a brand name like "weed-eater"? The generic term is just grease fitting. I've never seen a rating on the fittings, not saying it doesn't exist I just haven't seen it.
 
Just like we blow our nose with a kleenex and then grab a crescent wrench. 🙂

"The patent for the Zerk fitting was granted to Oscar Zerk in January 1929." <-- where the name caught on.
 
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