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Mercury Manometer

Mercury Manometer

Mercury Manometer

(OP)
Does anyone know where I can get some mercury to refill my manometer?

RE: Mercury Manometer

Perhaps you can recycle some of the evaporated Hg that ended up in your body?

RE: Mercury Manometer

Maybe it varies by geographic location, but mercury is considered pretty nasty stuff and it's use has some health and safety rules associated etc.

Does you manometer at least have some kind of filter or something?

KENAT,

Have you reminded yourself of FAQ731-376: Eng-Tips.com Forum Policies recently, or taken a look at posting policies: http://eng-tips.com/market.cfm?
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: Mercury Manometer

Time to switch to an electronic manometer...much more accurate and portable.

RE: Mercury Manometer

I remember the days when I was a kid I would smash a thermostat and play with the liquid mercury rolling around on the floor... Now a days you spill a drop and a hazmat team needs to be contacted for disposal.

RE: Mercury Manometer

ahhh, the good ol' days ... how ever did we survive them ?

how ever will we meet the challenges of the future with the current "nanny state" ideology ?

RE: Mercury Manometer

On the bright side people now go mad because of illegal street drugs or genetic reasons rather than the effects of widely used industrial chemicals, or maybe not.

Mad as a hatter anyone?

By the time I got to high school we were only allowed to watch the teacher play with mercury, couldn't do it ourselves.  I'd guess that's banned now.

KENAT,

Have you reminded yourself of FAQ731-376: Eng-Tips.com Forum Policies recently, or taken a look at posting policies: http://eng-tips.com/market.cfm?
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: Mercury Manometer

I rather suspect that mercury is now a banned substance.
It is in the EU where despite this everyone has to switch to fluorescent lights with mercuric compounds in them.
 

JMW
www.ViscoAnalyser.com
 

RE: Mercury Manometer

(OP)
so if its so hard to get ahold of - why does Dwyer sell mercury manometers?

RE: Mercury Manometer

Probably because for certain applications they offer performance benefits that outweigh the disadvantages.  Also, not everywhere has the same limitations on mercury, I'm sure there are markets in places where you can still play around with it in school.

KENAT,

Have you reminded yourself of FAQ731-376: Eng-Tips.com Forum Policies recently, or taken a look at posting policies: http://eng-tips.com/market.cfm?
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: Mercury Manometer

It was used and is still used at a high school by me in North Carolina. Some kids took some back in 2005 and Haz Mat shut the school down for 2 days scouring the school looking for it.. Kid dumped it in his backyard in a hole after hearing how "dangerous" it is.
Haz mat and 2 days of a school shut down for 8-12 ounces of Mercury missing..

http://www.wral.com/news/local/story/120690/
 

RE: Mercury Manometer

mcgyvr,

   I have just spent my morning trying to figure out how to manage ammonica for our blueprint machine.  I can find the stuff.  Disposing of it is proving to be a challenge.  I still haven't found anyone.  It looks like our machine is about to retire.

   I am glad I do not have a supply of mercury.

   A manometer is just a bent glass tube is it not?  I made an H2O manometer out of a piece of clear, flexible plastic hose once.   

               JHG

RE: Mercury Manometer

(OP)
Inches of water /= inches of mercury

RE: Mercury Manometer

(OP)
Not outright. I thought thats where drawoh was headin'. Nothing meant by my statement.

RE: Mercury Manometer

I think at most it was a suggestion you consider using a manometer with a less toxic fluid, not that you replace the mercury in the same unit with water.  Obviously, if water it would have to be about 13.6 times taller which may be an issue, but it's an idea.

KENAT,

Have you reminded yourself of FAQ731-376: Eng-Tips.com Forum Policies recently, or taken a look at posting policies: http://eng-tips.com/market.cfm?
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RE: Mercury Manometer

Mercury manometers are very useful and reliable for measuring low absolute pressures. I use them regularly. These days most engineers have no idea what they are or how to even read one. Because of this they also have a rather poor understanding of the distinction between gage pressure and absolute pressure. The toxicity of metallic mercury (quicksilver)is extremely exaggerated. It is almost impossible to be absorbed by the body, even when swallowed. that is why we didn't all die, or even get sick as kids. Mercury in the environment from fluorescent lamps and coal power plants is more of a problem.

Water manometers are only used for measuring small differential pressures. Water has a very high vapor pressure and will boil under vacuum. There are low vapor pressure oils that can be used but the low density means the gage will be tall.

RE: Mercury Manometer

The other thing banned in the EU as of today, it seems, are 100watt incandescent light bulbs.
As one of the few people to have been caught out and not having stockpiled a lifetimes supply (though I'm told they have a shelf life) I think what I need is an illegal source of supply).
Seems that instead of packing my suitcase with cigs, I'm gonna have to switch to light bulbs on my next trip outside the EU. Thought I had it last week till I discovered Latvia was a member state.

JMW
www.ViscoAnalyser.com
 

RE: Mercury Manometer

jmw

I just hope no one drops your suitcase!

Patricia Lougheed

******

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RE: Mercury Manometer

Quote (toastedhead):

Inches of water /= inches of mercury

   I wanted to measure pressure differences of around 0.1" H2O.  This would have been a challenge with mercury.  Converting from mercury to H2O might be fairly easy depending on your pressures, but you would still have to dispose of the mercury.

   My point was that I made a pressure gauge out of cheap stuff I bought at a hardware store.  If I can find mercury, I can make a mercury manometer.   
 

               JHG

RE: Mercury Manometer

Drawho, dilute your ammonia and give it to the janitor. It would be foolish to dispose of it as hazardous waste when you can buy it in the grocery store to clean floors.

RE: Mercury Manometer

jmw,

Just start using 150W lamps and connect a 1N4007 diode in the live lead to half-wave rectify the mains and drop the wattage a bit. The lamps last much better. It introduces a DC component and loads of harmonics into the distribution system but more importantly it gets around the stupid bloody rules made by stupid bloody politicians in Brussels who have nothing better to do with their worthless lives than interfere in ours.

/rant!
  

----------------------------------
  
If we learn from our mistakes I'm getting a great education!
 

RE: Mercury Manometer



Hg is hazardous and should be treated with caution.

Absorption through the skin is minimal, but the vapor pressure of Hg is such that it is harmful without proper ventilation. The hazard is that spills generate enourmous droplet fragments that are nearly impossible to recover except in a lab environment. The soluable Hg compounds are another matter entirely.

There are other high gravity liquids that can be used, not as handy as Hg, but easier to manage. The best bet is to use a proper transmitter.

 

RE: Mercury Manometer

"Drawho, dilute your ammonia and give it to the janitor. "

Or pour it on the lawn.

RE: Mercury Manometer

Hacksaw

"There are other high gravity liquids that can be used, not as handy as Hg, but easier to manage. The best bet is to use a proper transmitter."

What are they and do they really work? Many of the other other liquid metals wet glass and can't be sued in a manometer.

Toastedhead

Where did the Hg go? Why do you need more? If it evaporated there is a safety concern because Hg Vapor is the real hazard.

Whoever made the manometer should sell Hg. A google search for distilled mercury will get you several vendors.
 

RE: Mercury Manometer

OP has been silent w.r.t. the application for the manometer.  Is he just restoring an antique?

RE: Mercury Manometer

Out of curiosity I checked Dwyer's products. They do not make mercury manometers. They make manometers for measuring low differential pressures, not absolute pressures. You can fill their fluid manometers with whatever fluid you choose, typically water or oil.

My mercury manometers were made by Princo Instruments. They do not make them anymore.

RE: Mercury Manometer

That was the nice thing about manometers:  Anybody could bend a tube and fill it with a fluid and you could measure pressures with a simple scale (ruler).  No muss, no fuss, no calibration, no "we need to add A/D conversion, serial an wi-fi comms, programmable scaling, etc., etc.," ad infinitum.

Life was so simple for us dinosaurs.

old field guy

RE: Mercury Manometer

(OP)
Yo compositepro. In the directions for the Slack Tube manometer it states mercury can be used and they have it available - but I inquired about it and they specified they no longer carry it.

The slack tube was dropped and the mercury ran out.

Im moving to electronic from now on.

RE: Mercury Manometer

(OP)
Tell me about it. I went to the back to check up on some stuff and asked about the slack tube. "Oh we dropped it. We cleaned it up though."

"How?" I asked knowing that I didnt want to know.

"With a broom and a dust pan."

RE: Mercury Manometer

On all our slant tube manometers we used "Red Instrument Oil". in place of water.

http://www.grainger.com/Grainger/items/1TC00?cm_mmc=Google%20Base-_-Test%20Instruments-_-Pressure%20and%20Vacuum%20Measuring-_-1TC00


You fellows haven't been exposed to any mercury at all. Like everyone else with a little age we all have  played with mercury in school. I was ok until I killed my mother's wedding band. Mercury was used in the gas  meter at my house. Mercury was all over the college labs. When I started to co-op we had mercury all over the place, even the Orsat apparatus had mercury as the  controlling fluid.  When I started to  work after school we had Hg manometers for gauging tanks in the control rooms, 30 in 1. On the distillation side we used Hg manometers in the contol rooms for column differentials.  In a nearby paper mill they had all live instruments in the boiler control room so when a Hg instrument losted it fluid it probably fell on a hot steam line.

Mercury was extensively used in medicine at the time.
Calomel- ingested for everything that ailed you.
Yellow oxide of mercury-Used for infections especially the eyes.
Ammoniated Mercury-used in all types of ointments for external use.
Bichloride of Mercury-used to kill everything.
The Pharmacopeia of the time listed over twenty mercury compounds used in medicine.  

RE: Mercury Manometer

I have used plenty of mercury and water U-tube manometers back when I was a younger engineer.  Recently I had to verify that the gas pressure in my home was some certain value and I have long since lost my old manometers so I made one out of some clear plastic tubing (and some green food dye to make it easier to read-green was all the wife had at the time) to troubleshoot a troublesome tankless water heater.  When the technician arrived he thought I was nuts and would only accept the reading he took with his digital instrument.  It read what I had told them that the gas pressure was.

Speaking of mercury, what about the old kidney type pressure and differential pressure transmitters.  Bailey's, Hagan's, and others.  I've seen plenty of times that the mercury was just poured out on the ground and then they were refilled with fresh.  But then again, that was back when our kids were gnawing on window sills with leaded paint on them (as we did).  So what did we know.  Look at us and look at the idiots that society is producing today.  I think we should bring the lead and mercury back and we should play with it riding around in the open bed of a pick up truck.

rmw

RE: Mercury Manometer

Or maybe it's the long term effect of all that stuff catching up with uswinky smile.

Like many things I'm sure the potential effects of mercury have been exaggerated, doesn't mean everything that used to be done with it was a good idea though.

KENAT,

Have you reminded yourself of FAQ731-376: Eng-Tips.com Forum Policies recently, or taken a look at posting policies: http://eng-tips.com/market.cfm?
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?

RE: Mercury Manometer


The last mercury I saw purchased came from some place in Missouri. I called the lab where I use to work and they haven't bought any in years as what little they still use is refined in the lab. All their Mercury came from a Scientific supply house. As I understand it selling is banned in some states and some states you have to have a permit to buy, while a few offer no restrictions.


Leaded paint brought up another point that a lot of us grew up with, nearly all galvanized pipe joints were made up with white lead as the sealant. that included both water and gas. Mercury in the gas meter hooked up with lead in the pipe joints. A lot of farm buildings were painted with red lead based paints.
Where I grew up you couldn't have any white or light tone paints as the H2S in atmosphere turned the paint black in a couple of weeks.
The local creek has a film of coal tar creosote and phenol mixture and would periodically catch fire. It made a good dog dip as it cured everything, if the dog survived.
My father ran his 41 Chevy on 75% benzene + 25% gasoline during the war.
The gas metered into our house was water gas that had about 10% CO in the mix.
We didn't heat with gas, only cooked and heated water as we burned coal for heat so you didn't hang light colored clothes on the outside cloth's line.


I had a 25# tub of white lead oxide and created a big commotion when I carried it to the dump on one of the hazardous waste amnesty days.  

RE: Mercury Manometer

" I think we should bring the lead and mercury back and we should play with it riding around in the open bed of a pick up truck."

With or without helmets and pads? ;)

RE: Mercury Manometer

Most fillings in your teeth use amalgam which contains several % mercury.

RE: Mercury Manometer

One of me assignments in my instrumentation training was to overhaul a large characterized bell flow instrument. It contained 2 or 3 quarts of mercury.
 

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: Mercury Manometer

Amalgam fillings typically contain about 50% mercury.

RE: Mercury Manometer

I once lived in the North Louisiana / Southern Arkansas region and there was (and is) a big rhubarb about mercury in the fish caught in local rivers.  The rivers there don't drain any areas where there are a lot of minerals nor are there a lot of coal fired power plants which now seem to get the blame for all the mercury that exists in the land and the prevailing wind is off of the Gulf so that can't be blamed.

However, that region was one of the very first natural gas fields to be discovered in this country and my personal belief about the amount of mercury present is that it came from those old style kidney shaped flow meters like the one that Bill mentions above that were present everywhere throughout the gas field.  Plenty of those either had the mercury spilled as it was handled, or in the case of some (and I have seen this in many plants - mostly paper mills - in the region) when the temperature got cold, and they froze and burst the mercury spilled out.

It rarely gets very far below freezing in that area, but when it does, it takes a toll on exposed piping.  Back about 30 years ago, before electronics, the flow transmitters were all mercury pot or ring balance types.  Paper mills in the area used to take their major outages over Christmas when they were paying the operators and staff to be off anyway until one Christmas some time in the late '80's when they were all down and an unexpected and severe cold snap (cold for that region) rolled in and temperatures got down to 6 degF, a record for the region I think.  You could hear these old cast iron mercury filled meters going off like cannon shots all over the stone cold mill.  I still remember it.  There was nothing that could be done about it but just listen to all the mayhem.  It was weeks before they were able to get back up.

Point being, lots of mercury got spilled that day alone and I doubt that back in that day that was seen as much of an issue other than the replacement cost of the instruments that were destroyed and the excessive down time.  This mill drains right into the river in question.......  And there were several paper mills upriver just like it.  Go figure why the fish have mercury in them today.

rmw

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