Ask | Share | Grow™ - Question & Answer Community
Of the Members, By the Members, For the Members!
VacuumFurnaces.com is a Q&A community where vacuum furnace product and service suppliers connect with commercial and captive heat treaters to share their practical skills and know-how and to establish valuable relationships around niche topics of expertise with vacuum furnace end-users in operations, production, training, maintenance, marketing, sales, and engineering.
Burn in cycle for new hot zone
Furnace burn out (a.k.a. thermal cleaning) cycles are important part of vacuum furnace maintenance. It is meant to reduce and outgas contaminants inside the heating zone and within the insulation. For new hot zone it is more related to drying, conditioning and outgassing the remaining resin from insRead more
Furnace burn out (a.k.a. thermal cleaning) cycles are important part of vacuum furnace maintenance. It is meant to reduce and outgas contaminants inside the heating zone and within the insulation.
For new hot zone it is more related to drying, conditioning and outgassing the remaining resin from insulation manufacturing processes. Every new furnace should be burned out at it’s nominal temperature and I’d say this rule should also apply to any hot zone replacement. Your hot zone supplier should be able to tell you the nominal temperature of the hot zone.
Duration of burnout should be at least 2 hours at the temperature, however you may keep it longer if you see continuous improvement of furnace vacuum level.
Slow cooling is recommended after burnout.
IMPORTANT: The burn-out cycle is always performed with empty furnace. any tooling / fixturing and other equipment must be removed otherwise serious damage of furnace and tooling may occur.
See lessFor your own safety you should follow the OEM manuals.
What does it mean when a unit of measurement is raised to a negative power?
When a number is raised to a negative power, in fraction form it would be described as one over that number and its exponent (positive). See below: This is also how negative powers work when applied to units. The well known constituent units of the Newton (Force) kg*m/(s^2) could also be written asRead more
When a number is raised to a negative power, in fraction form it would be described as one over that number and its exponent (positive). See below:
This is also how negative powers work when applied to units. The well known constituent units of the Newton (Force) kg*m/(s^2) could also be written as kg*m*s^-2, and so on. The negative exponent would represent the ‘per’, e.g. kilograms meters ‘per’ second squared.
See lessWhat are the benefits of argon gas quench?
ARGON is an inert gas used in gas quenching, thus it has certain inherent advantages over liquid quenching media. Namely: Gas quenched materials have cleaner surfaces and experience less oxidation [1] Gas quenching allows for less deformities and more uniform cooling [1] Gas quenching is safer [2] GRead more
ARGON is an inert gas used in gas quenching, thus it has certain inherent advantages over liquid quenching media. Namely:
There are other gas quenching media, however. One (popular) gas is nitrogen. Nitrogen is more often used because it is cheaper with a faster cooling rate [3].
However, nitrogen can decarburize [3] or nitride [4] sensitive steels, whereas argon does not. Furthermore, when compared directly to nitrogen over a handful of samples, in most cases, argon quenched steel had slightly or significantly better mechanical properties [3].
References
[1] https://www.generon.com/nitrogen-quenching-system/
[2] https://www.lindeus.com/industries/manufacturing-and-materials-processing/gas-quenching-and-inerting
[3] https://www.industrialheating.com/articles/93972-comparing-argon-and-nitrogen-cooling-in-vacuum-furnaces
[4]https://www.boconline.co.uk/en/images/Principles%20of%20Quenching%20and%20Cooling_tcm410-114391.pdf
See lessAre vacuum furnace leak rates linear?
Leak rates are not typically linear in nature.
Leak rates are not typically linear in nature.
See lessWhen should we perform Temperature Uniformity Surveys (TUS)?
In general, we can say that there are two circumstances: 1) According to the frequency specified by the applicable standard (AMS2750, CQI-9, API) 2) When a modification is made to the equipment. Here it is important to be clear about the word "modification". In general terms, a modification is an alRead more
In general, we can say that there are two circumstances:
1) According to the frequency specified by the applicable standard (AMS2750, CQI-9, API)
2) When a modification is made to the equipment.
Here it is important to be clear about the word “modification”. In general terms, a modification is an alteration or adjustment that could affect the thermal characteristics of the equipment.
Both #AMS2570 and #CQI9 provide very clear guidance on what is a modification and what is not. Some examples of equipment modification:
If you want to learn more about these standards, you can follow the blog of Global Thermal Solutions LLC to find useful articles related to #heattreatment management.
See less