Do Zerk fittings have pressure ratings?

[Rubycon]

Named after the inventor.

Sorry about that I could not hear over the screech of a leaking Schrader valve overhead.

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.

 

[Dirigible]

I've known what they are (imagine, they used to be on CARS!), but had no clue what the ratings were.

Cars, shmars. I've got zerks to grease my mountain bicycle pivot bushings.

 

[bfdd]

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.

i love calling them adjustable spanners just to fuck with people.

 

[venkman]

zerk rush. g g g g g

 

[bobdole369]

Those jerks at Chrysler broke off my zerks. PT Cruiser has a "non-serviceable" chassis. One greasing is meant to last forever..... They are incorrect. My (and every other PT owners) worn bushings speak volumes.

 

[herm0016]

i do not think the grease fitting is the thing that is susposed to be holding the pressure back. in a wellhead valve ( gas well) rated at 15k there are zerks that are there to pack the threaded shaft but there are o ring seals inside that actually hold the pressure of the well back.

 

[Fritzo]

They used to, but everytime someone would try to mark them, they would get eaten by a grue.







Oh wait...sorry...sorry....those were Zork fittings. I always get those confused.

 

[Tsavo]

Named after the inventor.

Sorry about that I could not hear over the screech of a leaking Schrader valve overhead.

Step into a Jefferies tube for some much needed silence.

 

[Tsavo]

Step into a Jefferies tube for some much needed silence.

Scan it with a Geiger Counter first to ensure there's no dangerous radiation.

 

[Tsavo]

Scan it with a Geiger Counter first to ensure there's no dangerous radiation.

Jefferies Tube has a built in Faraday Cage, so she will not have to worry about stray radio waves.

 

[Tsavo]

Jefferies Tube has a built in Faraday Cage, so she will not have to worry about stray radio waves.

That's true, but don't bring your Tesla Coil into one...it will sound like a Theremin when exposed to the gamma suppressors inside the unit.

 

[Rubycon]

Jefferies Tube has a built in Faraday Cage, so she will not have to worry about stray radio waves.

Conjugate matching takes care of the strays.

 

[bfdd]

I'm so fn confused right now. Where's my bong?

 

[Rubycon]

I'm so fn confused right now. Where's my bong?

Mr. Mazzei has got a good kynar eductor waiting for you! Very smooth and absolutely inert!

 

[Greenmtn]

Maximum pressure observed was 7400 psi without failure. Most common equipment in our industry produces 3,000 psi max.

Maximum pressure has been addressed. Anyone knowledgeable regards minimum pressure? What does it take to open the check ball?

 

[herm0016]

holy necro batman

in my experience, it depends on how much dirt is in the ball and seat and how thick the grease is. if its clean and its a normal grease i would go for just a few psi to overcome the spring pressure.

Its hard to quantify.

what is going to be a larger contributor to that number is the pressure behind the ball. if you are greasing something that is at a working pressure it will be the few for the spring + the working pressure.

also, the area of that ball is tiny, so even at 10kpsi its not that much actual lbf.

 

[Greenmtn]

holy necro batman

in my experience, it depends on how much dirt is in the ball and seat and how thick the grease is. if its clean and its a normal grease i would go for just a few psi to overcome the spring pressure.

Its hard to quantify.

what is going to be a larger contributor to that number is the pressure behind the ball. if you are greasing something that is at a working pressure it will be the few for the spring + the working pressure.

also, the area of that ball is tiny, so even at 10kpsi its not that much actual lbf.

Thank you. This is very helpful. Assuming no back pressure and pumping at 3000psi, would you take a stab at GPM through a standard 1/4 x 24 zerk? Material is 600 to 800 cps.

 

[skyking]

fluid dynamics is a black art. I would not venture a guess on that.

 

[herm0016]

it is a black art, dimensionless numbers and coefficients that some dude figured out.

like a 30 wt grease? some "back of the envelope" calcs would call it .05 in^3 per s for a basic flow through and orfice calc. but its probably less than that. i would say could be different by 30% or so.

what the hell are you greasing? its a stab in the black arts. its been a min. from my fluids class. its going to be a small number. and small things have more variation from a calculation ime.


you can always measure it. get a zerk and a pressure gauge. hook up the guage to the output of the grease gun and put the zerk on somthing. pump to maintain constant pressure and use a stopwatch to measure 10 sec of it. measure the volume of grease. you can drop it into a known amount of water and measure the displacement or look up the density ( api standard charts, ex 30 wt or whatever it is on the can) and weigh the sample.

 

[Greenman]

it is a black art, dimensionless numbers and coefficients that some dude figured out.

like a 30 wt grease? some "back of the envelope" calcs would call it .05 in^3 per s for a basic flow through and orfice calc. but its probably less than that. i would say could be different by 30% or so.

what the hell are you greasing? its a stab in the black arts. its been a min. from my fluids class. its going to be a small number. and small things have more variation from a calculation ime.


you can always measure it. get a zerk and a pressure gauge. hook up the guage to the output of the grease gun and put the zerk on somthing. pump to maintain constant pressure and use a stopwatch to measure 10 sec of it. measure the volume of grease. you can drop it into a known amount of water and measure the displacement or look up the density ( api standard charts, ex 30 wt or whatever it is on the can) and weigh the sample.

He could just ask Ruby, she knows everything.

 

[Captante]

In Zerk, go you get eaten by a Gruo?

Not if you manage to kill the Wumpus first!

 

[herm0016]

Maximum pressure observed was 7400 psi without failure. Most common equipment in our industry produces 3,000 psi max.

Maximum pressure has been addressed. Anyone knowledgeable regards minimum pressure? What does it take to open the check ball?

He could just ask Ruby, she knows everything.

HA. i thought you were the one asking. i see now its your very similar named blue G avatar friend.

 

[Greenman]

HA. i thought you were the one asking. i see now its your very similar named blue G avatar friend.

An obvious imposter.