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CQI-9 Special Process: Heat Treatment System Assessment 4th Edition has been released! There are serious changes.

Considering that 33% of the world's heat treatment activities are carried out for the automotive industry, the renewal of CQI-9, the most important standard of this sector, is very important for the heat treatment community. The previous version was published in 2011. Let's see how long the new document CQI-9-4 will remain in force and what innovations it will bring to us.

CQI-9-4 heat treatment standard is very important for companies operating in the automotive industry. CQI-9 4th edition, cqi9 latest edition, cqi-9 latest version

What is CQI-9?

It is a heat treatment management system for the most common heat treatment processes used by automotive manufacturing and service parts providers. CQI-9 is published by Automotive Industry Action Group (AIAG) .

The standard, prepared with a group consisting of OEMs, tier 1 manufacturers, heat treaters and calibration companies serving them, is very important in terms of presenting the best practices with the knowledge gained from all over the world and preventing possible errors. With this standard, the heat processor has the necessary documentation to make its own self-assessment.

CQI-9 Special Process: Heat treatment system evaluation 4th edition review article begins!

CQI-9 version 4, cqi-9 revision 4, cqi-9 4th edition, aiag cqi-9 4th edition

The famous red and white page of CQI standards is no more.

The red landing page, which is familiar to friends who follow these standards, is now blue.

Assessor attributes have been changed

The internal auditor requirement in the first article of the HTSA ( Heat Treatment System Assessment) applicator's characteristics has been removed and a minimum of 5 years of heat treatment experience or equivalent metallurgical experience has been added to the first article, and in case there is more than one evaluator, the chief evaluator position has been given to the one with heat treatment experience. As someone who has dealt with HTSA evaluators who have nothing to do with heat treatment in the past, I really like this change. With CQI-9 4th edition, we will now work with people with whom we can speak the same language.

The cover page has been completely renewed.

Since I do not know if there is a legal responsibility to share the page here, I do not upload its image, but I think it will soon be available on the internet in Excel format. At first glance, I thought it had become more useful. Of course, my opinion may change over time as I fill it out.

Pyrometry reporting requirements have been updated.

RTDs (resistance temperature detectors) will now be included in thermocouple lists.

In the notes added to the maximum thermocouple usage numbers defined in Table 3.1.5, a lifetime of 1 year for "expandable" types and 2 years for "non-expandable" types has been introduced.

Additional periods determined for calibration, SAT (system accuracy test) and TUS (temperature uniformity survey) have been renewed.

The analog temperature controller will be phased out with CQI-9-4. cqi-9 version 4
With CQI-9-4 they will be a thing of the past in 3 years.

Analog recorders are becoming history!

Analog instruments must be replaced with digital ones within 3 years of the effective date of CQI-9-4.

I have good news for you. The maximum allowed offset values have been increased.

The values that were ±2.0°C or ±4°F in the old version have been changed to ±3.0°C or ±5°F. We will now be able to give the furnaces some more tolerance.

Restrictions were placed on the types of SAT thermocouples. Accordingly, only N, B, R and S type thermocouples can now be used.

New guidelines have been added for ovens that cannot be calibrated with traditional TUS applications.

The method of calculating the number of TUS thermocouples to be used in large furnaces has been renewed.

HTSA questions have been improved.

Question 1.6

A responsible person should be appointed to determine appropriate heat treatment processes with appropriate equipment.

Process changes should be recorded, reviewed and approved.

Question 2.15

Written approval must be obtained from the customer for test frequencies determined differently from the process tables.

Question 3.2

Questions regarding the calibration or verification of process equipment are detailed under subheadings.

There are revisions in a total of 6 questions: 3.3.-3.4 and 3.16.

Changes abound in process tables!

Many changes have been made to the process tables, and I will not be able to mention them all here due to their length. Just as the contents of the tables have changed, their names have also changed and a new table has entered the game.

Process table I: Hot stamping

"carbon correction" in Table A has been replaced by "carbon restoration".

The good news is that the calibration requirement for refractometers has been abolished. It is now sufficient to verify with distilled water before use.

Finally, ERRATA SHEET (correction document)

In all previous versions, AIAG had to publish an "errata sheet". There is no typo that catches my eye at first glance. If it catches my eye in the coming days, I plan to make a note here.

I tried to convey to you the changes that caught my eye in this heat treatment standard, which has been renewed over 9 years. More than 40 items have been changed in CQI-9-4, which consists of 116 pages. I hope that all innovations will move the heat treatment and automotive world forward and lead us to produce error-free products.

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