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What is an AMS2750 calibration survey?
Our blog post takes a short look at the AMS2750E standard, with a special focus on the requirements set for calibration, calibration accuracy, and test/calibration equipment. The AMS2750E is predominantly designed for heat treatment in the aerospace industry. Heat treatment is an essential process fRead more
Our blog post takes a short look at the AMS2750E standard, with a special focus on the requirements set for calibration, calibration accuracy, and test/calibration equipment. The AMS2750E is predominantly designed for heat treatment in the aerospace industry. Heat treatment is an essential process for many critical parts of an airplane, so it is understandable that there are tight regulations and audit processes set. While the results and success of some other industrial processes can be relatively easily measured after the process, this is not the case in a heat treatment process. Therefore, very tight control and documentation of the heat treatment process are essential to ensure the quality of the end products.>>>READ MORE
Source: Beamex Blog for Calibration Professionals
See lessHOW CAN I CELANÄ°NG CONTAMÄ°NATÄ°ON OF VACUUM FURNACES?
"When operating vacuum furnaces, situations may arise in which the hot zone and/or cold walls may become contaminated (Fig. Nos. 1 – 2). This can occur from a variety of sources: air leaks, outgassing from residues left on the parts as a result of the manufacturing or cleaning processes, vaporizatioRead more
“When operating vacuum furnaces, situations may arise in which the hot zone and/or cold walls may become contaminated (Fig. Nos. 1 – 2). This can occur from a variety of sources: air leaks, outgassing from residues left on the parts as a result of the manufacturing or cleaning processes, vaporization of sensitive materials (e.g., chromium-bearing materials), process-induced contaminations such as carbon in the form of soot or tar, fluxes from brazing pastes, excess braze alloy as well as many other sources. Often times the work being processed is also affected (Fig. 3). The question becomes, how do we attempt to clean up our contaminated vacuum furnaces? >>>Read More
Source: VAC AERO International
See lessNumber of SAT Thermocouples Required
According to paragraph 3.4.1.2. of AMS2750G: "The SAT shall be performed on all control and recording systems required by the applicable instrumentation type, as well as any additional recording systems used for parts and raw material acceptance in each control zone of each piece of thermal processiRead more
According to paragraph 3.4.1.2. of AMS2750G:
“The SAT shall be performed on all control and recording systems required by the applicable instrumentation type, as well as any additional recording systems used for parts and raw material acceptance in each control zone of each piece of thermal processing equipment used for production heat treatments.”
That means you should perform SAT on all control temperatures as well as any other temperature measurement system which are required by instrumentation type. For example Load thermocouples for instrumentation type A and B.
SAT is not required for overtemp systems (if overtemp protection is the only function of that system).
Each of those ‘systems’ (Thermocouple, TC wires, feedthroughs, and measuring/recording instrument) should be within SAT tolerance (which is 2F for class 1 equipment) to their SAT sensor.
See lessBurn 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.
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