In today's training, we learned about the importance of processing temperatures.
The international standard temperature is 20°C!
Today's training involved measuring the surface roughness of parts in the measurement room.
The school's measurement room is a thermostatic room.
The temperature at the time of measurement is fixed by international standards, and that temperature is 20°CIt is.
Although the dimensions are indicated on the drawings, they are only those at 20°C.
There are times when a part is made on site, measured and found to be perfect, but when delivered, it is just under tolerance.
This is caused by the difference between the temperature at the site and the temperature measured at the delivery site.
So, think about that,The teacher sets the component to a slightly larger value to createYes.
The temperature of metal rises in the processing machine, you know.
Iron and aluminum stretch so much when the temperature rises!
So how much does a metal expand with heat?
I hear it has something to do with the coefficient of thermal expansion, but to put it simply
When the temperature rises by 1°C, a 100-mm bar will stretch 1 μm in steel.
That is, if the dimensions were 100 mm,If it is 40 degrees Celsius during processing and 20 degrees Celsius during measurement, it will shrink by 0.02mmThat is to say.
It's bigger than you think. So it is important to cool it down by applying coolant.
To begin with, the word "coolant" comes from the idea of making COOL.
And what a surprise,Aluminum expands and contracts 2.3 times faster than steelThe following is a list of the most common problems with the
We have to be more careful.
Incidentally, the surface roughness measuring machine used in the thermostatic chamber at the vocational training school is this one from Mitutoyo.
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