Coolant Pump swap on a QTN250MS

[cwhuffman]

Has anyone "upgraded" or swapped the coolant pump out on an older Mazak lathe? In short, the coolant pump on my machine seems to be very underrated and is not capable of putting out a lot of volume or pressure. I am pretty sure it is the lowest pressure pump that Mazak offers on some of their turning centers. Running through coolant tools like 1" insert drills or turning tools is a bit painful as I cannot get the flow I need to cool the tool effectively. I thought perhaps the pump had some gunk built up in it, but upon inspection I could not find anything major. I have another Grundfros pump that is similar that I could swap out, but would require some modification to the tank to bolt up. I wanted to ask if anyone has done a swap like this before? What type/model of pump did you use? Was there something else impacting the flow like a clogged line or turret? Any help is appreciated as always.

 

[Philabuster]

I just bought a new in box Grundfos pump off ebay for my 1986 Mazak ST30 ATC/MC Lathe last week. I still need to machine an adapter plate for it. I will let you know how it goes.

 

[Steveabuster]

Has anyone "upgraded" or swapped the coolant pump out on an older Mazak lathe? In short, the coolant pump on my machine seems to be very underrated and is not capable of putting out a lot of volume or pressure. I am pretty sure it is the lowest pressure pump that Mazak offers on some of their turning centers. Running through coolant tools like 1" insert drills or turning tools is a bit painful as I cannot get the flow I need to cool the tool effectively. I thought perhaps the pump had some gunk built up in it, but upon inspection I could not find anything major. I have another Grundfros pump that is similar that I could swap out, but would require some modification to the tank to bolt up. I wanted to ask if anyone has done a swap like this before? What type/model of pump did you use? Was there something else impacting the flow like a clogged line or turret? Any help is appreciated as always.

We just recently purchased a QT10ATC and were able to drastically improve coolant pressure by disconnecting lines in various places and blowing through them backwards. I wish I could turn it down a bit now! LOL

 

[noname777]

install a simple throttle valve

 

[noname777]

Has anyone "upgraded" or swapped the coolant pump out on an older Mazak lathe? In short, the coolant pump on my machine seems to be very underrated and is not capable of putting out a lot of volume or pressure. I am pretty sure it is the lowest pressure pump that Mazak offers on some of their turning centers. Running through coolant tools like 1" insert drills or turning tools is a bit painful as I cannot get the flow I need to cool the tool effectively. I thought perhaps the pump had some gunk built up in it, but upon inspection I could not find anything major. I have another Grundfros pump that is similar that I could swap out, but would require some modification to the tank to bolt up. I wanted to ask if anyone has done a swap like this before? What type/model of pump did you use? Was there something else impacting the flow like a clogged line or turret? Any help is appreciated as always.

make sure you also replace KM13 or whatever ur mazak has as thermal protection relay for your new pump

 

[cwhuffman]

Thanks for the feedback everyone. The machine has a ball valve on the pump that you can use to control the flow rate, but it doesnt seem to really affect anything since it is such a low pressure output. I have been noticing though that the impellers inside the pump body seem to churn up the coolant pretty well. I removed the tank a few weeks ago to clean out chips and top off the coolant, and in the process I removed the pump from the tank to inspect it. Once I re-installed the pump, it was very bad about slinging coolant outside of the tank through the opening adjacent to where the pump is. It has always done this to an extent, but this seems to be the worst it has been. I have removed a lot of the "other" lines coming off the pump already which did help, but not much. I guess I need to undo them all and try to blow them out as suggested above.

 

[Steveabuster]

Thanks for the feedback everyone. The machine has a ball valve on the pump that you can use to control the flow rate, but it doesnt seem to really affect anything since it is such a low pressure output. I have been noticing though that the impellers inside the pump body seem to churn up the coolant pretty well. I removed the tank a few weeks ago to clean out chips and top off the coolant, and in the process I removed the pump from the tank to inspect it. Once I re-installed the pump, it was very bad about slinging coolant outside of the tank through the opening adjacent to where the pump is. It has always done this to an extent, but this seems to be the worst it has been. I have removed a lot of the "other" lines coming off the pump already which did help, but not much. I guess I need to undo them all and try to blow them out as suggested above.

My pressure increased at the tool by opening the coolant line somewhere between the tool holder and the where it changed from hard line to hose on the back of the machine. Then blowing backwards from the tool holder to the open line end. This made an huge difference. I also had a lot of sediment and chip build up in the block that floods everything from up above. I had to disconnect the line and blow it out backwards as well. I hope this helps. I have a QT10ATC. I assume they are all somewhat similar.

 

[cnctoolcat]

If you go for a replacement pump via Ebay, look for one with a high "head"---something like 70 meters or similar. Head rating equates to PSI, which is what you want for a CNC machine.

Pumps of similar horsepower and amp draw can behave very differently, depending on whether they are made for pressure or flow.

Usually the multi-stage centrifugal pumps are designed for CNC machining, and have high head ratings. If the pump section is taller than your tank, build a spacer of some sort to support the pump.

If there's not enough headroom to clear the pump's motor section, you can plumb a small auxiliary hydraulic tank (from Northern Tool or similar) alongside your main tank to mount your pump in.

ToolCat