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What type of water treatment do you recommend for a closed-loop cooling system?
Every closed-loop cooling system needs a modest amount of chemical treatment. Most are used once and then checked yearly. We recommend a sodium nitrite-based inhibitor with biocide to prevent biological contamination. This treatment is usually done at a 1% concentration so not much is needed. TheseRead more
Every closed-loop cooling system needs a modest amount of chemical treatment. Most are used once and then checked yearly. We recommend a sodium nitrite-based inhibitor with biocide to prevent biological contamination. This treatment is usually done at a 1% concentration so not much is needed. These inhibitors will protect both the ferrous and non-ferrous materials in your piping system. Many treatment chemicals come with a colorant which allows the treatment to be visually monitored.
Source: Dry Coolers
See lessWhat is the difference between ethylene glycol and propylene glycol?
ETHYLENE GLYCOL (EG)Is the green liquid we used to have in our car radiators. It’s the least expensive, hurts heat transfer the least, and hurts pump performance the least. It is toxic so its falling out of general usage. It is very corrosive so a suitable inhibitor package must be used to protect yRead more
ETHYLENE GLYCOL (EG)
Is the green liquid we used to have in our car radiators. It’s the least expensive, hurts heat transfer the least, and hurts pump performance the least. It is toxic so its falling out of general usage. It is very corrosive so a suitable inhibitor package must be used to protect your piping and equipment. Never use ethylene glycol for corrosion protection! Its only use is to prevent slushing and freezing of your coolant.
PROPYLENE GLYCOL (PG)
It’s the pink liquid we currently have in our car radiators. It’s about 20% higher in cost than EG, hurts heat transfer due to its high viscosity, hurts pump performance due to its high viscosity, and is needed in slightly higher concentrations than EG for equal freezing protection. Its winning appeal is its low toxicity. It is corrosive so a suitable inhibitor package must be used to protect your piping and equipment. Never use propylene glycol for corrosion protection! Its only use is to prevent slushing and freezing of your coolant.
DO NOT USE AUTOMOTIVE ANTI-FREEZE. Coolants for automobiles have inhibitors based on aluminum. Their inhibitor package is wrong for our industrial cooling systems.
Source: Dry Coolers
See lessWhat are common leaks usually found in the vacuum chamber?
Any pass-thru (penetration) is typical or common. Pass-thru's with heat are even more suspect, as heating and cooling cause movement of materials. Threaded fitting are notorious as thread lubricants (pipe dope) dry out over time. O-rings become flat due to heat/time and they can become dirty.
Any pass-thru (penetration) is typical or common. Pass-thru’s with heat are even more suspect, as heating and cooling cause movement of materials. Threaded fitting are notorious as thread lubricants (pipe dope) dry out over time. O-rings become flat due to heat/time and they can become dirty.
See lessWhat gases does a halide leak detector sense?
Chlorine based refrigerant gasses. Gasses drawn in through a probe hose are exposed to a flame heated copper reactor plate. If chlorine is present the flame changes color. Phosgene (poisonous) gas can be produced using halide leak detectors. Be very careful.
Chlorine based refrigerant gasses. Gasses drawn in through a probe hose are exposed to a flame heated copper reactor plate. If chlorine is present the flame changes color. Phosgene (poisonous) gas can be produced using halide leak detectors. Be very careful.
See lessWhat is the difference between a leak and a seep?
I don't believe these are real technical terms with definitive differences. My opinion is that a leak could be defined as gas and seep could be defined as liquid.
I don’t believe these are real technical terms with definitive differences. My opinion is that a leak could be defined as gas and seep could be defined as liquid.
See lessWhat is the difference between a leak rate and rate of rise?
If I understand the question, I believe the answer is they are the same. In the vacuum furnace industry, when we say "leak rate", we typically are measuring pressure as it rises to provide an indication of the in leakage of gasses into the vessel or furnace. This rise in pressure is called the "raRead more
If I understand the question, I believe the answer is they are the same. In the vacuum furnace industry, when we say “leak rate”, we typically are measuring pressure as it rises to provide an indication of the in leakage of gasses into the vessel or furnace. This rise in pressure is called the “rate of rise” when referenced over a period of time.
See lessHow to calculate rate of rise for leak check?
Pump the chamber down as far as practically possible, close the vacuum valve and measure the pressure rise over a period of time. Typically a rate of rise or leak rate is measured in a one (1) hour time period. If for example the pressure rises from 50 microns to 100 microns in one hour the rate oRead more
Pump the chamber down as far as practically possible, close the vacuum valve and measure the pressure rise over a period of time. Typically a rate of rise or leak rate is measured in a one (1) hour time period. If for example the pressure rises from 50 microns to 100 microns in one hour the rate of rise is 50 microns per hour. In other words you could say the leak rate is 50 microns per hour.
See lessHow frequently should leak testing be performed on vacuum furnaces?
Maybe once or twice a year, depending on many things. I recommend taking a leak rate (rate of rise test), after the furnace hot zone has been through a burn-out and cooled under vacuum, on a routine basis. This should be done maybe weekly or at least monthly and recorded. Eventually you will beginRead more
Maybe once or twice a year, depending on many things.
I recommend taking a leak rate (rate of rise test), after the furnace hot zone has been through a burn-out and cooled under vacuum, on a routine basis. This should be done maybe weekly or at least monthly and recorded. Eventually you will begin to see trends as the leak rate deteriorates. When the leak rate is determined to be to high, I would recommend a helium leak test using a mass spectrometer.
See lessHow to clean vacuum seals for vacuum furnace?
I would suggest using rubbing alcohol and a clean lint free rag.
I would suggest using rubbing alcohol and a clean lint free rag.
See lessWhat is an acceptable leak rates for o-rings?
An o-ring should not leak when tested with a helium mass spectrometer in the range of 10-6 or 10-7 Torr. Acceptable leak rates would be subjective and relate to the materials being processed in the furnace and the hot zone deterioration that can be tolerated with a leaking o-ring or system.
An o-ring should not leak when tested with a helium mass spectrometer in the range of 10-6 or 10-7 Torr. Acceptable leak rates would be subjective and relate to the materials being processed in the furnace and the hot zone deterioration that can be tolerated with a leaking o-ring or system.
See lessHow to grease a high vacuum o-ring?
Use a minimal amount of vacuum (silicone) grease. Just enough to make it shine. Grease collects dirt and dust leading to vacuum leaks.
Use a minimal amount of vacuum (silicone) grease. Just enough to make it shine. Grease collects dirt and dust leading to vacuum leaks.
See lessWhat is the service life expectancy of a vacuum furnace?
Typically if maintained well the life expectancy of a vacuum furnace should be 30 years or more. The critical component is the vessel. It is like the foundation of a house, and if maintained it will last a long time. Cooling water quality is critical to vessel life and longevity. All other compoRead more
Typically if maintained well the life expectancy of a vacuum furnace should be 30 years or more. The critical component is the vessel. It is like the foundation of a house, and if maintained it will last a long time. Cooling water quality is critical to vessel life and longevity. All other components can be repaired or replaces, but when the vessel deteriorates furnace life begins its demise.
See lessHow to use vacuum o-rings with or without grease?
I always recommend a slight film of vacuum (silicone) grease. Just enough to make it shine. Use as little grease as possible as it collects dirt which leads to vacuum leaks
I always recommend a slight film of vacuum (silicone) grease. Just enough to make it shine. Use as little grease as possible as it collects dirt which leads to vacuum leaks
See lessWhat is the shelf life of an o-ring?
I have had no problems using o-rings ten years old and maybe sometimes older. If they are pliable they should be fine.
I have had no problems using o-rings ten years old and maybe sometimes older. If they are pliable they should be fine.
See lessWhy is vacuum grease needed on o-ring installations?
Vacuum grease is not "needed" on o-rings to make a vacuum tight seal. Vacuum grease provides two things, 1) lubrication to allow for easier installation of the o-ring. 2) lubrication to allow movement of the sealing surfaces during evacuation. Grease is actually a detriment, as it collects dirt thaRead more
Vacuum grease is not “needed” on o-rings to make a vacuum tight seal. Vacuum grease provides two things, 1) lubrication to allow for easier installation of the o-ring. 2) lubrication to allow movement of the sealing surfaces during evacuation. Grease is actually a detriment, as it collects dirt that can eventually cause leaks.
See less