All;
What is the rule-of-thumb for TAN Alarm Limits of AW Hydraulic Oils and Gear oils.
Thanks for your assistance.
Original Post
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Dear CRB,
I am using ASTM D 6224 for reference
1. Analyze your fresh oil, to know your initial TAN
2. The inservice oil shall not exceeding:
- For Hydraulic: Initial TAN + 0.2
- For Gear: Initial TAN + 0.5
Regards
Nurudin
I am using ASTM D 6224 for reference
1. Analyze your fresh oil, to know your initial TAN
2. The inservice oil shall not exceeding:
- For Hydraulic: Initial TAN + 0.2
- For Gear: Initial TAN + 0.5
Regards
Nurudin
During my last tour through The Amusement Park (tech service), before they punished me for enjoying my work too much with a job in Quality, I was getting concerned about the usefulness of TAN.
An old rule of thumb for turbine oils was 'Worry when it hits 0.5 mg KOH/g'. But I was seeing a number of in-service samples that reached TANs around 0.5 quite a bit sooner than expected. Further, the oils looked pretty good otherwise with regard to RPVOT, FTIR, water and any other analyses you'd expect to possibly correlate with a high TAN.
This phenomenon appeared to be occurring with newer formulations that used Grp II & III base stocks.
Has anyone else observed anything like this? And does anyone need a cynical smart-ass to make snide comments while conducting tech-service work? I hate my current job with a raging, seething passion and would probably pay you for the right position.
An old rule of thumb for turbine oils was 'Worry when it hits 0.5 mg KOH/g'. But I was seeing a number of in-service samples that reached TANs around 0.5 quite a bit sooner than expected. Further, the oils looked pretty good otherwise with regard to RPVOT, FTIR, water and any other analyses you'd expect to possibly correlate with a high TAN.
This phenomenon appeared to be occurring with newer formulations that used Grp II & III base stocks.
Has anyone else observed anything like this? And does anyone need a cynical smart-ass to make snide comments while conducting tech-service work? I hate my current job with a raging, seething passion and would probably pay you for the right position.
LBD;
I have to say that I am also not convinced of the suggested usefulness of AN as it is drummed up by almost everyone in the business. I’ve also seen oils with elevated AN up to a “suggested” upper limit or above it, but with good RBOT, exhibiting negligent to low deposit buildup, and passing copper corrosion test with flying grades. The “industry set/suggested “ limits reminds me on gospel from car manufacturers (with blessing from oil companies) that sets life limit for a particular motor oil by strongly suggesting oil replacement after certain mileage (e.g. 3000 or 5000 or…). One shoe does not fit everyone. Never did and never will. IMO, AN should never be looked at as the sole vital or condemning factor for any oil, but rather in a context with other oil characteristics that AN dances with.
And, no, I have not observed the phemon you described, at least not with turbine oils formulated with Group 2 stocks; they all had AN in 0.01 to 0.05 range.
I have to say that I am also not convinced of the suggested usefulness of AN as it is drummed up by almost everyone in the business. I’ve also seen oils with elevated AN up to a “suggested” upper limit or above it, but with good RBOT, exhibiting negligent to low deposit buildup, and passing copper corrosion test with flying grades. The “industry set/suggested “ limits reminds me on gospel from car manufacturers (with blessing from oil companies) that sets life limit for a particular motor oil by strongly suggesting oil replacement after certain mileage (e.g. 3000 or 5000 or…). One shoe does not fit everyone. Never did and never will. IMO, AN should never be looked at as the sole vital or condemning factor for any oil, but rather in a context with other oil characteristics that AN dances with.
And, no, I have not observed the phemon you described, at least not with turbine oils formulated with Group 2 stocks; they all had AN in 0.01 to 0.05 range.
