Mori SL1H Turret Problem (Help source Solenoid Valve Body)

[Tuff Luck Tom]

I have had a Mori SL1H with Centroid conversion for a few years. It's been a rock solid machine. And I rather like the Centroid conversion. My turret had been a little strange from time to time but it was so seldom it was not a big problem. All of a sudden I can't rely on it to make a tool change that is more than a few pockets at a time. I am still thinking it may be a hall effect sensor. But some hydraulic noises and advise have had me check the solenoid and valve. I found the spool valve to be heavily grooved. There are part numbers on the solenoid coils but I am looking to buy just the valve. Doe's anyone know what it might be (the valve)? The machine has been down a week now and it's my only cnc lathe. I've got quite a lot to run through it and am a bit cash flow strained till I can get it going again. Any advise will be greatly appreciated!!!

 

[Tuff Luck Tom]

Ok shrunk down some photos to fit. If needed I can pull it again there are 3 letters cast into the other side of the valve body. I am hoping I can get away with replacing just the valve. Any thoughts? The solenoid coils are p/n 02-101731

 

[Garwood]

Good idea on the pictures.

How did you test the valve?

 

[Tuff Luck Tom]

Good idea on the pictures.

How did you test the valve?

Really, only pulled it apart and found that scoring on one side of the spool valve. The other side is in perfect shape. Along with indexing problems I can see on the machine diagnostic i/o display that the turret will seem to be clamped visually but the Hall Effect sensor isn't reading it as clamped. At this point I force the outputs to stop clamping then unclamp then reclamp and after one cycle like this the clamped Input is lit. I am not positive the valve is the problem but it does appear to be a problem. But that may be a poor assumption? Some one with knowledge of my plc program suspected it could be the solenoid/clamping feature and that along with what may be a new hydraulic noise heard at the turret led me to checking the valve. I am not positive the noise it Hydraulic it could be the motor but I have only heard it a few times.

 

[Tuff Luck Tom]

I have also adjusted the reluctor collar and this has made it so I can at least change tools making the command of a tool or 2 at a time. I see no pattern of shared hall effect sensors on the tools that do not index properly. Although tool 2 indexes too far every time if I index from tool 3 to tool 2 (7 tool positions). The other faults seem to be sometimes it doesn't think it is clamped closed or most commonly slightly under rotates at this point I can pull the turret the rest of the way into position. The only time it over rotates is on tool 2. All of this seems to be new as of last week although it has been quirky a few times in the past but it is an isolated incident here and there. Now it's totally not right. The hydraulic pump does have good pressure although it may be advantageous to see if there is a pick up screen I can clean.

Also at the beginning of this issue last week it blew one leg on the thermal overload for the turret. I have replaced it with one off ebay...

 

[newcomer]

Seems like a combination of issue. In this case it'd be wise to fix the simpler problem i.e the valve. Use a small bore gauge to measure the valve body to ensure the bore has not worn to an unusable state. Send the spool for hard chrome and grind it to size. Fit tolerance should be sliding fit. Note hard chroming can't build up more than ten thous typically. You may need to machine a new spool in that case.
Too much effort? Just bring the valve to your local hydraulic shop and have them find a matching unit for you. Or just buy one online they aren't really very expensive unless it's the name brand ones like Vickers or Parkers.
Your valve looks like a typical 5/2 way valve which is super common. There's a diagram on the body just to be sure. T means tank, P for pump, A & B refers to the ports.

 

[DouglasJRizzo]

If you have a parts book, Mori probably has the part. Won't be cheap, but they probably have it.

 

[Tuff Luck Tom]

Seems like a combination of issue. In this case it'd be wise to fix the simpler problem i.e the valve. Use a small bore gauge to measure the valve body to ensure the bore has not worn to an unusable state. Send the spool for hard chrome and grind it to size. Fit tolerance should be sliding fit. Note hard chroming can't build up more than ten thous typically. You may need to machine a new spool in that case.
Too much effort? Just bring the valve to your local hydraulic shop and have them find a matching unit for you. Or just buy one online they aren't really very expensive unless it's the name brand ones like Vickers or Parkers.
Your valve looks like a typical 5/2 way valve which is super common. There's a diagram on the body just to be sure. T means tank, P for pump, A & B refers to the ports.

I may make a spool this weekend to see if it will get me by. I'll make a trip to the Hydraulic shop this week and see what they have to say. I was expecting it to be a some what common part so I am glad to hear you think it will be. Thank you for your response!

 

[Tuff Luck Tom]

I don't think the scoring on the valve is wear. I think it's poor machining and not the problem. After a little more inspection I realized the area that looks bad does not come into contact with any of the rest of the assembly and the wear would not be radial. The part of the spool valve that contacts the valve body is seemingly in good shape.
I assume when Hall Effect sensors begin to go they can become weak?

 

[Bill in PA]

The shaft splines on my turret are worn. Successful tool indexing greatly depends on the balance of the turret. I always keep a tool holder at each position, even if it is empty.

You may want to make sure there are no chips around the proximity sensors. I have tried adjusting mine. I could make the indexing worse but not much better.

Bill

 

[Tuff Luck Tom]

That is interesting. Mine went from running well with few turret indexing problems to half the time not quite being far enough. I adjusted the reluctor collar which the Hall Effect sensors read and it became better at indexing one tool at a time. There is a little movement when the turret is unclamped. I believe it to be in the worm gear. The thing that has me wondering about the sensors is that a tool change from 3 to 2 (a 7 position index) results in tool 2 being far below center. So past position by at least one curvic coupling position. The other positions that do not load properly some times are slightly under rotation and I can pull the turret into position by hand. There is no obvious correlation between the sensors that are used for T2 and the tools that under rotate. I am currently running with programs edited to cycle through the tools one at a time and hit the end of a part run yesterday (30 parts) that way.

I think I am going to order an oscilloscope as I've been wanting one for side project stuff. I'm thinking I can hopefully identify an offending Hall Effect Sensor. But it's new territory for me and maybe I am on the wrong path all together.

 

[Bill in PA]

My turret would only be off far enough that the coupler teeth would clash. It always needed to go a little further. Never went too far like yours. Certain positions seem to "clunk" more than others.

Bill