Internal calibration lab

[table]

We would like to establish an internal calibration department. It'll be about 10 m2, contain air-conditioner etc.
Any advice would be appreciated. (What kind of devices we have to buy, which one is useful and has good quality? What are the most important things that we should pay attention?)

Ozan

 

[table]

Sorry I fotgot to write down; Our lab will be dimensional calibration lab and we'll calibrate micrometers, calippers...

 

[PSE]

If you are working with these types of tools, then it is helpful to have reference standards (gage blocks etc) to measure. Keep your references as simple as possible and make sure that these reference standards are traceable to an appropriate standards institute (In the U.S. it would be the National Institute of Standards Technology or NIST). Send these standards out to a re-certification body periodically and keep the results documented. Include information as to how many generations removed from the actual national standard the reference is. It is also helpful to conduct gage R&R studies on each gage used in order to have a document available on expected accuracy. In one location that I worked we mandated that instrumentation used to measure critical or key characteristics must have a gage R&R of <10%. &quot;Normal&quot; gages could have an R&R as high as 20% (according to the internally set policy). Your controlled environment is very beneficial to your accuracy (control humidity as well). Set a calibration schedule for each measurement tool and keep the results documented.

Good luck,

 

[randi]

There is an excellent book for calibration labs:
Fundamentals of Metrology by Wilkie Brothers Foundation, by Ted Bush, Delmar Publishers, Albany, New York, U.S.A.

In running a lab you would need some very basic inspection and repair tools, working standards and reference standards that would be traceable to Natinally certified standards. As
per age old practices a ratio of 10:1 was desirable, but some say that due to highly increased accuracy of devices used this ratio ( between the working and the calibration standard) is now down to 1:3 or 1:5. Anyway this is a user defined value. For verniers and micrometers you would need a
set of gauge blocks that come in various grades and materials
and sizes ( 40 or 80 pc set etc). They are also available in special lenghts for special measurements. If you ever use thread mikes then you would need pin gauges also. Mitotoyo also sells calibarion kits for verniers and mikes. Unless you have a reasonable number of mikes and verniers for calibration on a frequent basis, an outside service agency is better, unless you are in this business. In that case you also need to become a certified lab to ISO 9000 and then to a national certifying body.MIL Q-9858, later on an ASQC calibration standard and currently ISO 9000 lays down the requirements for a calibration system.