Nitrogen rig question

[avbug]

Also not particularly relevant. Further, if you think you're successful because the local FSDO doesn't bust you, remember that whereas the FSDO doesn't have the authority to interpret regulation or grant liberties not available from the manufacturer or national, another FSDO certainly has the right and opportunity to pursue enforcement action or declare a repair unairworthy...an important point during a sale, later inspection, or in the event of an incident involving any legal action (such as an insurable event).

Simply substituting something because you think it's "better" is isn't bright, nor legal. The subject is a whole lot more complex than such simplistic thinking.

 

[erj-145mech]

My point was they, Piper and Cessna really messed up in the old days when they chose inferior materials in certain areas. 1960's and 70's mostly.

Do you think that Cessna and Piper built thousands of aircraft inferior materials, and the Federal Government turned its back?

The materials and the processes met the standard at the time. Just like your private pilot checkride, it also met the standards at the time. Now a days, the applicant must be proficient in radio communications and VOR navigation.:laugh:

The Volkswagon Beetle, thousands were sold in the US in the 60's and 70's. Until recently, they were built in Mexico and Brazil, but none were sold in the US. Do you know why? Answer is that they didn't meet the current standards. If the new Piper company were to certify your J-3 under the current standards, it wouldn't pass muster either.

 

[Frozen Ronin]

For kids sake, Avbug! What you ought to be asking this guy is if he is using high pressure nitrogen or if he's got a step down regulator!!!! He's made up his mind, and the FAA really won't care.

Nitrogen rigs can be either high pressure, for using on 121 type struts, or low pressure, such as for GA struts (amoung other things). The bottles used are the same, 3000 psi. The difference is in the regulator rig, and that's where the pressure is stepped down for GA stuff, tire servicing and the like. You could really hurt yourself, no, you can KILL yourself if you use the wrong one. This, in my opinion, is far more important than if you use shop air versus nitrogen, no?

I know of more than one mechanic that died because he hooked up a high pressure rig to a low pressure strut. This is no joke, don't dismiss it, do not pass go and do not collect 200 bucks.

Be safe.

Ronin

 

[avbug]

I believe we already addressed the issue of putting too much pressure to the strut, right off the bat. A regulator is a regulator...perhaps you're talking about strut pumps. The poster was never asking about that. The poster wasn't asking about a strut pump, or a regulator,though I did caution him or her about putting too much pressure to whatever he or she is pumping (particularly if they think it isn't moving because the shraeder valve isn't open...).

What the poster was asking about was a threaded adapter to attach at the shraeder valve or filer valve...and that adapter fitting won't change the pressure at all.

A strut pump is a horse of an entirely different color.

 

[Frozen Ronin]

Ah, now we shift the focus to debating my facts. If you'd like, I'll go into how regulators are drastically different for high and low pressure. Maybe in a different thread. Most of these differences stem from loss of life. I wonder if those who were injured or killed thought that all regulators were the same? I think the point is being missed on this one.

The adapter is very important as far as pressure, as well.... many operators are going to a larger shrader or filler valve to show the difference between high and low pressure applications. This goes for tires to accumulators to e bottles to struts. It's all in the name of safety.

Strut pumps are fun, when you don't have high pressure available. I've not read any loss of life related to them, but that doesn't mean it hasn't happened.

Ronin

 

[erj-145mech]

If a regulator regulates to 200 psi, then it is 200psi. it doesn't matter if its a high or a low pressure regulator.
It only matters if the knucklehead cannot read a pressure gauge, and I have run into a few of those.

 

[avbug]

Ah, now we shift the focus to debating my facts.

What on earth are you talking about?

If you have a pride issue invested in your "facts," good for you. Whatever.

The point was made at the outset that one needs to be careful when applying pressure to a strut...but that's really beside the point when the poster is talking about a little brass fitting, and asking where to get one.

The topic was never regulators.

Seeing as you're upset about debating your "facts," and seeing as I didn't address any of your "facts," let's do so, then.

Nitrogen rigs can be either high pressure, for using on 121 type struts, or low pressure, such as for GA struts (amoung other things).

Fact: there is no such thing as a 121 type strut.

Fact: there is no such thing as a GA strut.

Fact: as ERJ-Mech stated...200 psi dialed into a regulator is 200 PSI.

Fact: various regulators are available in varying capacities, but a properly calibrated regulator will put out the same pressure that's demanded of it it, period.

I know of more than one mechanic that died because he hooked up a high pressure rig to a low pressure strut.

Stupidity hurts. But perhaps you know of more than one mechanic who merely put too much pressure to a strut...period. Rather than using a "high pressure regulator" on a low pressure strut.

Presumably you're attempting to describe two stage regulators which will include two pressure gauges; one will show the input pressure from the nitrogen source (bottle or rig), with the other showing the output pressure as set by the user. Both high pressure and low pressure output regulators will have the same input...both will show bottle pressure. However, a typical lower pressure regulator will be able to output 0-300 PSI, where whereas other regulators capable of delivering higher pressures will generally show 300-3,500 PSI in the output range.

Further, many units utilize manifolds with multiple attach points for doing more than one strut at the same time, to the same identical pressure, with a common pressure gauge. These are often aircraft specific, and are not uncommonly fabricated in the field.

The use of a "high pressure" regulator does not mean one is going to blow up a component. I've used "high pressure" regulators for years for struts and tires. How it is used makes the difference in the end result...but the thread here isn't about teaching someone to service a strut. It's about a poster who ran over the brass fitting and wanted to replace the fitting. Read the thread before responding, next time, and try not to get too excited. You might just blow a gasket.

 

[IFollowRoads]

It only matters if the knucklehead cannot read a pressure gauge, and I have run into a few of those.

Truth.