Pressure gauges are tools used to measure the pressure at any given point. You can do this by generating an electric current and measuring the potential difference between two locations. Pressure gauges come in all shapes and sizes but typically use some form of mercury as a working fluid. When using a pressure gauge for measuring, pressurize the area to get an accurate reading. Ensure you avoid any corrosive substances; otherwise, your gauge will not work properly.
When using a pressure gauge, you will need a few items, such as a cup, to hold the mercury; make sure this cup is airtight. You will also need to have an area where you can place the pressure gauge so it can read the pressure at that location. If you are filling a mercury tube with water, avoid any form of a magnetic field; otherwise, you could damage your pressure gauge. These magnetic fields can also interfere with your readings because they change the movement of your mercury.
When using a mercury pressure gauge, ensure you know the area’s temperature since this can change the pressure. If you are near a magnetic field and your pressure gauge is not appropriately shielded, you will have to recalibrate it by submerging it in water and reading the scale through the glass. This problem of magnetic interferences can also be fixed by submerging your mercury into the water since water is diamagnetic.
How then do you calibrate a mercury pressure gauge?
First, read the instructions of where you purchased your gauge if there are any.
To calibrate your pressure gauge, you will need the following materials: mercury, an airtight container, a stopwatch, and a needle. Fill up your airtight container with mercury, place it on your stopwatch, and fit in the needle. Place the stopwatch on top of the needle and start counting from when you put in the pressure gauge until it stops reading pressure. Then wait one day; this process can be done overnight if needed. You will need to fill your airtight container with mercury again and repeat the steps above to ensure it works properly. This calibration process can be repeated until you get an accurate reading.
Each time you refill your cup of mercury, make sure you have a bubble-free surface since this could cause inaccurate readings due to the surface tension of the liquid. This will usually happen once you get out of the 1st clean bubble. If you have a stronger surface tension, this will happen sooner. You can fix this by adding mercury to your container’s water.
Another tip you can use with your pressure gauge is putting a thin layer of insulation on top of the mercury, so it doesn’t evaporate when out in direct sunlight.
Once you calibrate your pressure gauge, you can use it for almost anything. For example, you can use your calibration to check if you have a leak in your home by putting a tube filled with liquid (such as water) and bringing it to the roof of the house. You can use this method to test for leaks, whether from your pipes, kitchen faucet, or bathroom sink.
Lastly, you can use your pressure gauge to check if the seal of your bottle cap is watertight by filling it with water and checking for leaks. If you live in an area with a lot of earthquakes, you can use your pressure gauge to test if your house has cracks in the walls that could cause fractures during an earthquake.
If you need to test the pressure of your tires on your car, you can check the level of the tire by using Mercury, the same way you calibrate your gauge. You will need to grab a plastic container that is big enough to fit inside your tire, submerge it with water, and wait for the bubbles to clear. If there are no bubbles underneath or around your tire, it is under-inflated. You will also have to do this for each wheel of your car.
Another pressure gauge tool is to check the amount of water in a particular spot, such as a pool. This can be done by placing your gauge on top of the water and checking for bubbles. If there are no bubbles, you know there is no pressure inside the pool.
These are only a few ways you can use a pressure gauge. Most of these will require you to calibrate your gauge. Calibration may be needed if you want to test something that requires exact measurement, and once you get it calibrated, you will be able to use it for many other things.
You can buy a pressure gauge for your home or business and make sure you know what you need, as there are many variations, such as digital pressure gauge, and dial pressure gauge. They all have different uses, so ensure you get the right gauge for your needs.