Verniers for use in pharmaceuticals

[jakaodrz]

Does anybody knows is there any suggestion for what type of verniers to use in laboratories acording to GMP ?
I know that metal verniers are used everywhere but still do not know what are the suggestions of using them in pharmaceuticals.

 

[quark]

I don't know any rules as to the use of verniers. We have all kinds of verniers, the simple manual ones, the circular dial types and the electronic ones. I generally prefer Mitutoyo make only.

I don't see any probelm, if you get them regularly calibrated.

 

[jakaodrz]

I supposed that there is no particular rule for them. I was in confrotation with one of my collegues because she says that she only works with fiber verniers. She got one, but it has been used for 7 years and has deformations on it (error of almost 0.3 mm, with not paralel jaws). Also, searching thru various offers it seems that there is no big option for fibre verniers.

 

[quark]

I am not sure what a fibre vernier is. Is it a manufacturers name? In any case, don't go by name. What you should have is a calibrated calliperse with calibration tracing to national standards.

 

[jakaodrz]

Fibre means made by glass fiber(strenghten), not from stainless steel.

 

[EdStainless]

I would use the electronic metal ones. There are no crevices or gears to trap debris. I would also make sure that they have carbide working faces. They should last for decades.

= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection

http://www.trent-tube.com/contact/Tech_Assist.cfm

 

[quark]

I concur with EdStainless. Your collegue, alone, can say what is the advantage of going for a fibre glass vernier. The material and construction of a gauge should be in such a way that it should give minimum distortion, backlash, wear and tear etc.

Can you let us know what is her exact suggestion, may be we can learn something out of it.

 

[jakaodrz]

Well, she used it for 7 years, and I can see that there is a distorsion of material with error readings.
The only positive thing is that measuring the tablets (diameter, height) do not make any possibilty of destroying them (smashing, press deformation from metal jaws). I doubt this is the pro fact to use it. I thnik if the operator knows that there shouldn't be any use of additional force when measuring tablets, there wouldn;t be any deformation of tablets.

 

[EdStainless]

Don't you check tables sizes with go-nogo gages? A plate with a series of holes. I would think that if they are in size you are fine.
I can't believe that plastic calipers (even decent fiberglass ones) are rigid enough and accurate enough to provide any real process control information.
If you do need exact sizes you have a couple of other options.
You can get calipers with spring loaded jaws to limit the force applied.
You can also get snap gages, just a dial indicator on a frame, that you set up for each job. You measure the deviation from the nominal size. These use very low forces.

= = = = = = = = = = = = = = = = = = = =
Rust never sleeps
Neither should your protection

http://www.trent-tube.com/contact/Tech_Assist.cfm