The changes from AMS2750F to AMS2750G include revisions and updates to the pyrometric requirements for equipment used in the thermal processing of metallic materials. The AMS2750G specification covers temperature sensors, instrumentation, thermal processing equipment, correction factors and instrument offsets, system accuracy tests, and temperature uniformity surveys. These changes are necessary to ensure that parts or raw materials are heat treated in accordance with the applicable specifications. The purpose of AMS2750G is to ensure that parts or raw materials are heat treated in accordance with the applicable specifications.

The revision from AMS2750F to AMS2750G mainly consists of administrative changes rather than significant technical changes. One notable change is that digital recording instruments are not required to read to the tenth of a degree until one year after the release of AMS2750G. Additionally, over temperature controls have been given a permitted error within AMS2750G, which was not present in revision F.

To comply with AMS2750G, suppliers who already conform to AMS2750F should find the transition relatively straightforward. It is recommended to consult experts or training courses that specialize in AMS2750 standards and Nadcap requirements to ensure compliance. Calibration services and process certification services can also be helpful in meeting industry standards.

Some specific changes between AMS2750F and AMS2750G include:

Revision G marking: Historically, AMS2750 did not mark the revision when released using change bars, unlike other AMS specifications. However, when AMS2750F was revised to revision G, change bars were included. This makes it easier for suppliers to understand the modifications and account for those changes internally.

Extensive changes: AMS2750G is considered a complete rewrite of the specification, and there are no change bars to indicate specific changes. The changes are extensive and cover various aspects of pyrometry requirements.

It is important to refer to the official AMS2750G specification for a comprehensive understanding of all the changes and updates.

For more detailed information and updates on AMS2750G, you can visit the SAE International website or refer to the Conrad Kacsik blog post on the differences between AMS2750F and AMS2750G.

SOURCES:

Pyrometry AMS2750G – SAE International

Differences Between AMS2750F and AMS2750G – Conrad Kacsik

Using a clean and controlled environment in vacuum heat treating is important for several reasons:

1. Contamination prevention:

Vacuum heat treating involves subjecting materials to high temperatures in a controlled atmosphere. Any contaminants present in the environment can react with the material or form unwanted surface layers, leading to discoloration or other quality issues. By maintaining a clean environment, the risk of contamination is minimized, ensuring the integrity of the heat-treated parts.

2. Consistent results:

A controlled environment helps in achieving consistent and repeatable results during the heat-treating process. Contaminants or impurities can introduce variability in the heat treatment process, leading to inconsistent outcomes. By eliminating or minimizing the presence of contaminants, the heat-treating process can be more predictable, resulting in consistent and reliable results.

3. Surface quality:

Cleanliness of the environment is crucial for achieving desired surface quality in heat-treated parts. Contaminants can cause surface imperfections, such as stains, discoloration, or pitting, which can affect the appearance and functionality of the parts. A clean environment helps maintain the desired surface finish and appearance of the heat-treated parts.

4. Material integrity:

Some materials are sensitive to contamination and can react with certain elements present in the environment. For example, reactive metals like titanium can easily react with oxygen, nitrogen, or carbon, leading to surface discoloration or degradation. By using a clean and controlled environment, the risk of such reactions can be minimized, preserving the integrity of the material.

5. Process efficiency:

A clean environment can contribute to the overall efficiency of the vacuum heat-treating process. Contaminants can interfere with heat transfer, affecting the uniformity of temperature distribution within the vacuum chamber. By ensuring a clean environment, heat can be transferred more efficiently, leading to faster and more effective heat treatment cycles.

In summary, using a clean and controlled environment in vacuum heat treating is essential to prevent contamination, achieve consistent results, maintain surface quality, preserve material integrity, and enhance process efficiency.

When working with high vacuum (HV) and ultra-high vacuum (UHV), there are specific aspects to consider ensuring an efficient and safe system.

To clarify, the pressure range of UHV conditions are defined as between 10-7 and 10-12 mbar, whereas HV conditions are defined as between 10-3 and 10-7 mbar. Some of the main applications of HV include metallurgical processes, nuclear physics, space simulation and analytical instruments. On the other hand, UHVs are used for surface analysis, in high-energy physics and Molecular Beam Epitaxy (MBE).

Here are the four main considerations you need to bear in mind when working under HV or UHV conditions.

1. Vacuum systems design, materials, and surfaces.
2. Managing working conditions and cleanliness.
3. Choosing the right pump technology.
4. Conductance influence.

Source: Vacuum Science World – Four basic rules for working under HV and UHV conditions.