manometer calibration

[Gabriele Russo]

Like for sfignomanometers, is it possible to calibrate the manometer of the
floor pumps (I hold my aged one dear)?
In facts, the only place I see where doing it is the techno-assistance
medical centers.
GR

 

[Michael Dart]

Gabriele Russo wrote:
> Like for sfignomanometers, is it possible to calibrate the manometer
> of the floor pumps (I hold my aged one dear)?
> In facts, the only place I see where doing it is the techno-assistance
> medical centers.
> GR

Check under "instrument calibration"?

We have a calibration bench in the instrument shop where I work (papermill).
There may be some outside sources available in your area or near the
industrial part of town.

Mike

 

[Dan]

"Gabriele Russo" <[email protected]> wrote in message
news:[email protected]...
> Like for sfignomanometers, is it possible to calibrate the manometer of
the
> floor pumps (I hold my aged one dear)?
> In facts, the only place I see where doing it is the techno-assistance
> medical centers.
> GR
>

Look in the yellow pages for testing laboratories. Find one that has a "dead
weight tester" These are very common.

http://www.instrumentation2000.com/catalog/calibrators/0304.html

 

[Ryan Cousineau]

In article <[email protected]>,
"Gabriele Russo" <[email protected]> wrote:

> Like for sfignomanometers, is it possible to calibrate the manometer of the
> floor pumps (I hold my aged one dear)?
> In facts, the only place I see where doing it is the techno-assistance
> medical centers.
> GR

As several people have suggested, there are high-grade calibration
services available for industry, where this stuff matters.

For the cost of one calibration session, you could just buy one really
good manometer (what a wonderful name for a pressure gauge; Since I have
given up "brifteur" I shall use "manometer" more often) and use it as a
reference, or buy several cheap ones, and use the average of their
readings as a reference. You could do all kinds of neat graphs showing
the distribution of the cheap meters' pressure readings, which would
probably be Gaussian, and would impress us greatly (Robert Chung could
put it up on his site!)

Cheap and silly,
--
Ryan Cousineau, [email protected] http://www.wiredcola.com
Verus de parvis; verus de magnis.

 

[Dave Reckoning]

"Ryan Cousineau" <[email protected]> wrote in message
news:[email protected]...
> In article <[email protected]>,
> "Gabriele Russo" <[email protected]> wrote:
>
>> Like for sfignomanometers, is it possible to calibrate the manometer of
>> the
>> floor pumps (I hold my aged one dear)?
>> In facts, the only place I see where doing it is the techno-assistance
>> medical centers.
>> GR
>
> As several people have suggested, there are high-grade calibration
> services available for industry, where this stuff matters.
>
> For the cost of one calibration session, you could just buy one really
> good manometer (what a wonderful name for a pressure gauge; Since I have
> given up "brifteur" I shall use "manometer" more often) and use it as a
> reference, or buy several cheap ones, and use the average of their
> readings as a reference. You could do all kinds of neat graphs showing
> the distribution of the cheap meters' pressure readings, which would
> probably be Gaussian, and would impress us greatly (Robert Chung could
> put it up on his site!)
>
> Cheap and silly,
> --
> Ryan Cousineau, [email protected] http://www.wiredcola.com
> Verus de parvis; verus de magnis.

My observation has been that these inexpensive manometers most often tend to
read high rather than low (saying there is more pressure than there really
is). I suspect that it is due to the fact that the calibrated version was
made with more precision and therefore had less friction in the indicator
and the production runs tended to have lower quality pivots and thus read
lower with the same mechanism.

I like the idea of the array of inexpensive manometers though.

Dave

 

[Brian Huntley]

Ryan Cousineau wrote:
> For the cost of one calibration session, you could just buy one
really
> good manometer (what a wonderful name for a pressure gauge; Since I
have
> given up "brifteur" I shall use "manometer" more often) and use it as
a
> reference, or buy several cheap ones, and use the average of their
> readings as a reference. You could do all kinds of neat graphs
showing
> the distribution of the cheap meters' pressure readings, which would
> probably be Gaussian, and would impress us greatly (Robert Chung
could
> put it up on his site!)

Would this output be called 'manograms?'

I recall performing an experiment in mech-o-mats class once that
involved presurizing a system with multiple gauges, and was facinated
that one gauge was showing far less pressure than the other. This was a
dumb move, as it turned out, 'cause my lab partner and I horribly
overpressurized the system while staring at the sticky dial, and
something let go, and we were knocked back several meters, our ears
ringing.

It was a bit like the old saw about a man with two clocks never knowing
what time it really is, only more painful.

 

[Jim Smith]

"Brian Huntley" <[email protected]> writes:

> Ryan Cousineau wrote:
>> For the cost of one calibration session, you could just buy one
> really
>> good manometer (what a wonderful name for a pressure gauge; Since I
> have
>> given up "brifteur" I shall use "manometer" more often) and use it as
> a
>> reference, or buy several cheap ones, and use the average of their
>> readings as a reference. You could do all kinds of neat graphs
> showing
>> the distribution of the cheap meters' pressure readings, which would
>> probably be Gaussian, and would impress us greatly (Robert Chung
> could
>> put it up on his site!)
>
> Would this output be called 'manograms?'

No. Those are what you get on valentines day. Not that there is
anything wrong with that.

 

[Leo Lichtman]

This is bugging me. All the years I spend studying and doing engineering, a
*manometer* was a U-tube with liquid in it. Pressure or vacuum was applied
to one or both legs, and the difference in the height of the liquid was
proportional to the pressure difference. What you guys are talking about
were always called *gauges.* Gauges need calibration--manometers don't. It
is because of the use of manometers that pressures are often specified in
"inches of water," or "inches of mercury." This is so common that even some
gauges are calibrated in inches. Vacuum gauges are ALWAYS calibrated in
inches or cm of mercury, though this traces back to barometers more than
manometers.

 

[Jim Smith]

"Leo Lichtman" <[email protected]> writes:

> This is bugging me. All the years I spend studying and doing engineering, a
> *manometer* was a U-tube with liquid in it. Pressure or vacuum was applied
> to one or both legs, and the difference in the height of the liquid was
> proportional to the pressure difference. What you guys are talking about
> were always called *gauges.* Gauges need calibration--manometers don't. It
> is because of the use of manometers that pressures are often specified in
> "inches of water," or "inches of mercury." This is so common that even some
> gauges are calibrated in inches. Vacuum gauges are ALWAYS calibrated in
> inches or cm of mercury, though this traces back to barometers more than
> manometers.

I thought so too, but I looked it up and "manometer" is just a synonym
for "pressure gauge." It appears that it is correct to speak of
"U-tube manometers," "aneroid manometers," etc.

 

[Marty]

Leo Lichtman wrote:
> This is bugging me. All the years I spend studying and doing engineering, a
> *manometer* was a U-tube with liquid in it. Pressure or vacuum was applied
> to one or both legs, and the difference in the height of the liquid was
> proportional to the pressure difference. What you guys are talking about
> were always called *gauges.* Gauges need calibration--manometers don't. It
> is because of the use of manometers that pressures are often specified in
> "inches of water," or "inches of mercury." This is so common that even some
> gauges are calibrated in inches. Vacuum gauges are ALWAYS calibrated in
> inches or cm of mercury, though this traces back to barometers more than
> manometers.
>
>

I was thinking the exact same thing. That's the beauty of manometers,
they're always accurate. I can't imagine a manometer for measuring tyre
pressure unless you have a mercury one, which is increasingly rare these
days. Mind you, pressure measurements are always suceptible to confusion
because of the many different units.

Marty

 

[Leo Lichtman]

"Jim Smith" wrote: (clip) It appears that it is correct to speak of "U-tube
manometers," "aneroid manometers," etc.
^^^^^^^^^^^^
My old Webster's Unabridged agrees with you. Had I taken the trouble to
look it us, as you did, I probably would have written my posting
differently.
However, the dictionary does not agree with today's usage. Dictionaries are
supposed to follow accepted usage, not lead it, nor limit it. I believe
that the OP's difficulty in finding a calibration source stems from this.
Looking back, you will see that he said, "The only place I see doing it* is
the techno-assistance medical centers."
*calibrating manometers.

 

[Jim Smith]

"Leo Lichtman" <[email protected]> writes:

> However, the dictionary does not agree with today's usage.

I agree. I certainly picture a tube full of fluid when I hear
"manometer." I also just googled "aneroid manometer" and almost every
link has something to do with blood pressure.

 

[[email protected]]

On Sun, 24 Apr 2005 16:06:27 +0800, Marty <[email protected]>
wrote:

>Leo Lichtman wrote:
>> This is bugging me. All the years I spend studying and doing engineering, a
>> *manometer* was a U-tube with liquid in it. Pressure or vacuum was applied
>> to one or both legs, and the difference in the height of the liquid was
>> proportional to the pressure difference. What you guys are talking about
>> were always called *gauges.* Gauges need calibration--manometers don't. It
>> is because of the use of manometers that pressures are often specified in
>> "inches of water," or "inches of mercury." This is so common that even some
>> gauges are calibrated in inches. Vacuum gauges are ALWAYS calibrated in
>> inches or cm of mercury, though this traces back to barometers more than
>> manometers.
>>
>>
>
>I was thinking the exact same thing. That's the beauty of manometers,
>they're always accurate. I can't imagine a manometer for measuring tyre
>pressure unless you have a mercury one, which is increasingly rare these
>days. Mind you, pressure measurements are always suceptible to confusion
>because of the many different units.
>
>Marty

Dear Marty,

To check road bicycle tire pressures, a mercury manometer
would require the roof of a two-story house. To measure 100
psi, you'd need 203.6 inches of mercurcy, or 17 feet.

Carl Fogel

 

[Leo Lichtman]

<[email protected]> wrote: To check road bicycle tire pressures, a
mercury manometer would require the roof of a two-story house. To measure
100 psi, you'd need 203.6 inches of mercurcy, or 17 feet.
^^^^^^^^^^^^^^^
Well, you COULD bore a hole in the ground to the required depth--when the
mercury comes to the top of the hole, stop pumping. <g>

 

[LioNiNoiL_a t_Y a h 0 0_d 0 t_c 0 m]

Leo Lichtman wrote:

> the dictionary does not agree with today's usage [of "manometer"].
> Dictionaries are supposed to follow accepted usage, not lead it,
> nor limit it. I believe that the OP's difficulty in finding a
> calibration source stems from this.

Editors of dictionaries have a hard time keeping up with changes in
usage ["semantic drift"], made harder by the absence of any standard for
"accepted usage". The case of "manometer" is not an especially bad
example of this drift, though, because it originally meant 'a measure
for thinness [of air]': "manos" = thin, "metron" = a measure [Greek]. A
pressure gauge in this sense is indeed a manometer.

--
"Bicycling is a healthy and manly pursuit with much
to recommend it, and, unlike other foolish crazes,
it has not died out." -- The Daily Telegraph (1877)