I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids?

No. Hydrofluoric will eat all stainless steels, although for
300-Series grades above 316, the problem is pitting rather than just
getting eaten away.

Hydrochloric also attacks these grades, although the effect is much
less. With most 300 grades, it eats the iron and leaves a
nickel/chrome smut.

With sulfuric, it depends on the concentration; it produces various
effects.

Stainless is not a good material to use with most acids. If you need
to use metal -- or nearly anything else -- you'd better do some
research. Here's a start:

http://www.engineeringtoolbox.com/me...nce-d_491.html

If you're tempted to look into machinable ceramics, like Macor, forget
it. They generally contain a glassy phase that is vulnerable to some
acids.

--
Ed Huntress


The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

On Saturday, June 20, 2015 at 12:57:55 PM UTC-4, Gerry wrote:
Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

My first thought is to think about using a stainless nozzle with a CPVC liner. So the acid does not touch the stainless. The stainless will eventually fail, but it might be good enough to last much longer.

Dan

In article , Ed Huntress
wrote:

On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in
quart and gallon plastic bottles. It will be used with phosphoric, HCl,
sulfuric and hydrofluoric acids in fairly high concentrations. The fill
nozzles are made from CPVC and are made to by-pass when the bottle gets
filled to a certain level. They are prone to breakage. I need to remake them
in a material/design that will reduce the breakage. My question is is there
a stainless alloy that would hold up to these acids?

No. Hydrofluoric will eat all stainless steels, although for
300-Series grades above 316, the problem is pitting rather than just
getting eaten away.

Hydrochloric also attacks these grades, although the effect is much
less. With most 300 grades, it eats the iron and leaves a
nickel/chrome smut.

With sulfuric, it depends on the concentration; it produces various
effects.

Stainless is not a good material to use with most acids. If you need
to use metal -- or nearly anything else -- you'd better do some
research. Here's a start:

http://www.engineeringtoolbox.com/me...nce-d_491.html

If you're tempted to look into machinable ceramics, like Macor, forget
it. They generally contain a glassy phase that is vulnerable to some
acids.

Any metal you may use will dissolve in the acid, and contaminate it.
Depending on the grade of acid, this may ruin the acid as a salable
product.

What causes the breakage? Perhaps all that's needed is more robust
physical design. And teflon is immune to most acids.

Joe Gwinn

On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

Molybdenum is a possibility.
http://www.mtialbany.com/metals/molybdenum/

It's not difficult to machine, once you're aware of its quirks. It's
quite abrasive and prone to chipping, otherwise machines much like
cast iron.

Tungsten is generally more resistant than moly to acids, both hot and
cold, but is considerably more expensive and not fun at all to
machine.

Take this advice for what it is, a couple possibilities based on
experience with the materials mentioned.

--
Ned Simmons

On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

Teflon is the material. The secret to machining Teflon is a razor
sharp tool bit. If you don't worry about loosing a finger every time
you pick up or touch the tool, it is not sharp enough.

wrote in message ...

On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids
in quart and gallon plastic bottles. It will be used with phosphoric, HCl,
sulfuric and hydrofluoric acids in fairly high concentrations. The fill
nozzles are made from CPVC and are made to by-pass when the bottle gets
filled to a certain level. They are prone to breakage. I need to remake
them in a material/design that will reduce the breakage. My question is is
there a stainless alloy that would hold up to these acids? The part of the
nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone
machined into one end and threads on the other. Rather than redesign the
whole CPVC nozzle I am wondering if I can just turn the piece that fails
with something stronger. Any comments/suggestions will be appreciated. TIA

Teflon is the material. The secret to machining Teflon is a razor
sharp tool bit. If you don't worry about loosing a finger every time
you pick up or touch the tool, it is not sharp enough.
================================================== ==========

The main thing I hate about Teflon is how it cold flows, so seals like
compression ferrules eventually dig in and leak, even with regular
tightening. How about virgin UHMW polyethylene? The bottles you are
filling are probably PE so the chemical compatibility is there, and it is
much cheaper than Teflon and doesn't cold flow nearly as much. It is softer
and more flexible than CPVC but doesn't stress crack nearly as bad, so there
is a good chance the life will be better. If you really need them cheap use
one of those quick prototyping places and get 100-500 injection molded :-).
Then just replace them often enough to keep them from breaking while
filling.

-----
Regards,
Carl Ijames

On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

Id suggest glass.

On Sat, 20 Jun 2015 14:08:43 -0700, Gunner Asch
wrote:

On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

Id suggest glass.

No glass. Even borosilicate glass won't handle hydrofluoric acid.

--
Ed Huntress

Gunner Asch on Sat, 20 Jun 2015 14:08:43 -0700
typed in rec.crafts.metalworking the following:
On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

Id suggest glass.

Which would work for all but the hydrofluoric acid. Which eats
glass, if memory serves. Fluorine compounds, go figure.
--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."

HydroFloric eats that for lunch. Frosted glass is frosted with that
acid. Otherwise I think you are ok.

Maybe a line or special nozzle for HFL and another for others.

Martin

On 6/20/2015 4:08 PM, Gunner Asch wrote:
On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

Id suggest glass.

On Sat, 20 Jun 2015 20:44:18 -0700, pyotr filipivich
wrote:

Gunner Asch on Sat, 20 Jun 2015 14:08:43 -0700
typed in rec.crafts.metalworking the following:
On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

Id suggest glass.

Which would work for all but the hydrofluoric acid. Which eats
glass, if memory serves. Fluorine compounds, go figure.
--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."

Ayup.

https://thechronicleflask.wordpress....gh-everything/

Gunner Asch on Sat, 20 Jun 2015 22:16:07 -0700
typed in rec.crafts.metalworking the following:
On Sat, 20 Jun 2015 20:44:18 -0700, pyotr filipivich
wrote:

Gunner Asch on Sat, 20 Jun 2015 14:08:43 -0700
typed in rec.crafts.metalworking the following:
On Sat, 20 Jun 2015 09:57:53 -0700 (PDT), Gerry
wrote:

I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

Id suggest glass.

Which would work for all but the hydrofluoric acid. Which eats
glass, if memory serves. Fluorine compounds, go figure.
--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."

Ayup.

https://thechronicleflask.wordpress....gh-everything/

http://pipeline.corante.com/archives...difluoride.php

Here's how the experimental prep of today's fragrant breath of spring
starts:

The heater was warmed to approximately 700C. The heater block
glowed a dull red color, observable with room lights turned off. The
ballast tank was filled to 300 torr with oxygen, and fluorine was
added until the total pressure was 901 torr. . .

And yes, what happens next is just what you think happens: you run a
mixture of oxygen and fluorine through a 700-degree-heating block.
"Oh, no you don't," is the common reaction of most chemists to that
proposal, ". . .not unless I'm at least a mile away, two miles if I'm
downwind." This, folks, is the bracingly direct route to preparing
dioxygen difluoride, often referred to in the literature by its
evocative formula of FOOF.
{end quote}

A torr is Aprox 1mm of Hg ; ergo 901 torr is about 1.1 Atmosphere.




--
pyotr filipivich
"With Age comes Wisdom. Although more often, Age travels alone."

On Saturday, June 20, 2015 at 9:57:55 AM UTC-7, Gerry wrote:
I am working ... to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage.

If it hasn't been suggested already, materials ARE available that won't take any
harm. Synthetic sapphire, for instance, can be routinely made in tube form
(but it'll likely be a special-order item). Suppliers say that tubes are easily
formed.
This website specifically mentions Stepaniv process for tubes:

http://www.alteo-alumina.com/en/sapphire

On Saturday, June 20, 2015 at 12:57:55 PM UTC-4, Gerry wrote:
I am working on a packaging machine that is used to package various acids in quart and gallon plastic bottles. It will be used with phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high concentrations. The fill nozzles are made from CPVC and are made to by-pass when the bottle gets filled to a certain level. They are prone to breakage. I need to remake them in a material/design that will reduce the breakage. My question is is there a stainless alloy that would hold up to these acids? The part of the nozzle that breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone machined into one end and threads on the other. Rather than redesign the whole CPVC nozzle I am wondering if I can just turn the piece that fails with something stronger. Any comments/suggestions will be appreciated. TIA

In addition to the material selections suggested by others, I'd be looking at WHY the nozzles are breaking. Perhaps you could fix this with better positioning or timing? I recently fixed a machine that had been giving the operators fits for years simply by moving a sensor to a place where it got a cleaner shot at the product going by, greatly improving the repeatablity of the system.

Of the materials selected, sapphire gets my vote as the most exotic, but UHMWPE is so friggin easy to machine...

"rangerssuck" wrote in message
...
On Saturday, June 20, 2015 at 12:57:55 PM UTC-4, Gerry wrote:
I am working on a packaging machine that is used to package various
acids in quart and gallon plastic bottles. It will be used with
phosphoric, HCl, sulfuric and hydrofluoric acids in fairly high
concentrations. The fill nozzles are made from CPVC and are made to
by-pass when the bottle gets filled to a certain level. They are
prone to breakage. I need to remake them in a material/design that
will reduce the breakage. My question is is there a stainless alloy
that would hold up to these acids? The part of the nozzle that
breaks is a tube, roughly 3/8" OD with a 1/4" ID with a cone
machined into one end and threads on the other. Rather than redesign
the whole CPVC nozzle I am wondering if I can just turn the piece
that fails with something stronger. Any comments/suggestions will be
appreciated. TIA

In addition to the material selections suggested by others, I'd be
looking at WHY the nozzles are breaking. Perhaps you could fix this
with better positioning or timing? I recently fixed a machine that had
been giving the operators fits for years simply by moving a sensor to
a place where it got a cleaner shot at the product going by, greatly
improving the repeatablity of the system.

Of the materials selected, sapphire gets my vote as the most exotic,
but UHMWPE is so friggin easy to machine...

============================================
What are the bottles made from?