Keep replacing Mazak QTN450-2 Spindle Cooling fan/motor

[ERIC14779]

We had a Spindle cooling fan overtemp alarm back last spring, Maintenance replaced it and all was well until this week when it did it again, The operator opened up the end of the machine and put a floor fan blowing on the Spindle cooling fan and continued running.... It seems to be when we are making heavier cuts that this happens.

 

Now the alarm is the Spindle cooling fan itself not the spindle, there is a thermal switch in the Spindle cooling fan motor that is tied to a input. We have plenty of air flow to cool the spindle.... everything seems normal no other high temps.... just the little Spindle cooling fan

 

Myself and the maintenance manager think that something weird must be going on... There is no way we should have to replace the Spindle cooling fan again...

 

 

Has anybody else had this issue? I am thinking a power quality issue (internally to the machine) or a magnetic field from the spindle affecting the Spindle cooling fan.

 

Mazak said last year that they have not seen many of these Spindle cooling fan go bad...

 

thanks

[tycobbwildwood]

We had a Spindle cooling fan overtemp alarm back last spring, Maintenance replaced it and all was well until this week when it did it again, The operator opened up the end of the machine and put a floor fan blowing on the Spindle cooling fan and continued running.... It seems to be when we are making heavier cuts that this happens.

 

Now the alarm is the Spindle cooling fan itself not the spindle, there is a thermal switch in the Spindle cooling fan motor that is tied to a input. We have plenty of air flow to cool the spindle.... everything seems normal no other high temps.... just the little Spindle cooling fan

 

Myself and the maintenance manager think that something weird must be going on... There is no way we should have to replace the Spindle cooling fan again...

 

 

Has anybody else had this issue? I am thinking a power quality issue (internally to the machine) or a magnetic field from the spindle affecting the Spindle cooling fan.

 

Mazak said last year that they have not seen many of these Spindle cooling fan go bad...

 

thanks

Hi we have a 2008 nexus 510 mill and nexus 200 lathe.I have had the problem 2 times we came to the conclusion we were having a power problem from not enough power.Both times i shut em off for 10 minutes and all was fine not sure if they are the same problem but i have had the alarm good luck.

[ERIC14779]

tycobbwildwood,

 

Yeah I am thinking it has to be something weird.... The fan motor bearings are fine, sounds fine, spins freely..... both on the one we replaced last year and the one that is now giving the alarm... on occasion.

 

when I was looking at it yesterday the machine had been running for hours. the operator had a 18" floor fan blowing on the cooling fan.

 

I felt the temp of the motor and it was not even warm !!!!

 

if there was a problem you would think that the motor would always be hot to the touch.... (( *shrugs* ))

[ERIC14779]

been researching.....

 

I think the fan motor is a Capacitor RUN (PSC) type...

 

and possibly the Capacitor is going bad or I have a loose connection to it ( the capacitor is mounted in the electrical cabinet)

 

We are going to replace the Cap and see what happens....