Alarm 130 - Possible causes/function

Guys, brainstorm session requested.


I've been getting frequent 130 errors, and today I took the time to investigate.

( all this is on a '06 vintage VF4 with gearbox )

So, after removing the front cover, I've noticed that the drawbar moves down a bit slowly for the first 1/4" or so, then the unclamp solenoid kicks on and it unclamps solidly.
Then, on the return it moves back up solidly until perhaps .250 short from top, and then moves wicked slowly all the way up.

So, after researching for possible tests, here is what I've found:

1: Return spring is NOT broken.
2: Removing the precharge airline ( the one on the right side ) DOES restore the solid clamp/unclamp cycle, obviously without the intermediate stop point ( the function of the precharge )
3: Removing the muffler from the main unclamp solenoid DOES NOT fix the problem.
4: Removing the muffler from the pre-charge solenoid manifold DOES NOT fix the problem. ( sidenote: do not do this unless you are Antman!!! )
5: Precharge regulator makes a "snorting" noise when activating. With finger on regulator it does vibrate as if air has trouble passing by.

So, in an attempt I have removed, disassembled and cleaned the pre-charge regulator. Was careful enough as to not move the stem from it's current setting.
After re-assembly and re-install, the return cycle got noticeably quicker and steadier. Again, did not adjust the pre-charge pressure ( nor checked it at the time but ... )

Now, after about 100 unclamp/clamp cycles I have not had any alarms, but! I did notice that when the tool is fully clamped it sits there for approx 2 seconds before the
carousel shuttle returns to home.
Ergo: I did NOT fix the problem, but I did something.

So, now here is the question for a possible discussion: How does the unclamp/clamp cycle SHOULD work?
In my mind, the idea is this:
1: When UNCLAMP is commanded, the Pre-charge solenoid opens. This air is now routed through a pressure regulator set to about 4-5 PSI, and then this air is
sent to the unclamp piston. With this lower pressure the piston gently moves the drawbar to be in contact with the belleville as to not smack them hard.

2: After a pre-set amount of time the main unclamp solenoid opens. It is routed through a check valve Tee, which now fully extends the drawbar.
At the same time of the main solenoid's opening the pre-charge solenoid turns off. ( question #1 later )

3: When the tool is inserted and RECLAMP is commanded, the main solenoid turns off and drawbar piston is forced back by the belleville washers first to the intermediate position,
then the return spring takes over and pushes the drawbar all the way up and activate the prox switch, signaling that tool is now fully clamped. ( question #2 )

So, question #1: How does the check valve Tee supposed to work? Why is there a muffler on the main solenoid if the check valve not supposed to let air back into it?

Question #2: How does the air in the piston supposed to escape upon clamp? Is it through the check valve back to the main solenoid's muffler, or is it through the precharge
regulator to the precharge solenoid manifold?

I am a bit baffled, mostly because I've noticed that the pressure regulator appears to be connected "backwards", meaning the port with the arrow pointing as OUT is hard piped to the
solenoid manifold.

Just a related question - how clean is the incoming air, is it very dry with no oil mist?

Air supply is from a Kaeser screw with a refrigerated dryer.
No particulate filter on the supply, but dry and oil-free.

For the record, while the upper part of the VF's head was covered with oil all over ( likely not the least unusual ), the disassembled regulator was absolutely spotless inside.
I've washed it with warm water and Palmolive, but it was truly as clean as it gets.
So were the filters. I actually saw light through the sintered brass just after removal.

haastec last posted on 6/13. Maybe pm him and see what his thoughts are?

I admit to whispering a little prayer every time I start my machines, begging them to work correctly and not throw error messages.

Aside from the pneumatics, drawbar operation is normal? Force good, no likelihood of broken bellevilles?

Milland said:

Aside from the pneumatics, drawbar operation is normal? Force good, no likelihood of broken bellevilles?

Click to expand...

Nope, all is well once tools are clamped and used.

Again, drawbar motion is smooth to and fro, no chatter, toolmarks, accuracy or life degradation whatsoever.

Well, this bit about one of your regulators possibly being installed backwards means I'd take a picture of the setup and post it here, or email to your local HFO, and get their take on it. But whether that's the actual problem I can't say, TBH it's a little hard for me to follow your order of failure mode (but that's likely my text to brain processing).

If nobody here has any bright ideas maybe a video showing the clamping issue, or plumbing a gauge inline with the "stages" of operation and recording pressures would help.

Milland said:

Well, this bit about one of your regulators possibly being installed backwards means I'd take a picture of the setup and post it here, or email to your local HFO, and get their take on it. But whether that's the actual problem I can't say, TBH it's a little hard for me to follow your order of failure mode (but that's likely my text to brain processing).

.

Click to expand...

I am absolutely certain that the regulator is installed as-intended by design and not an assembly line screwup.
First, it has been flawless for 12+ years ( probably a mill or more clamps ).
Second, physically it is impossible to install any other way as the regulator is actually a cross with bottom port to supply, left port to piston, top port vent, right port press. gage ( if used )

As far as the "mechanics" behind the double solenoid is rather simple.
Low pressure to ease the drawbar down onto the belleville springs, then high pressure to open drawbar.
Then on the return all air is off, strong belleville springs return the drawbar to clamp the tool, weaker return springs to send it all the way up to home.

But, a picture is worth a thousand words: Overview - Drawbar - Tool Change - Full Sequence - Video | Customer Resource Center

Nice animation, would be even better with the full staging of the solenoid shown (unless it does and it's too subtle for me to notice).

I have heard of the main piston getting "sticky", would that help explain your situation? Have you ever had that apart?

Certainly not the main piston as that requires removal of the spindle motor ( and I ain't goin' there )
The opening is always solid, it's only the return to the fully retracted position.

Well, I think you said you pulled lines that would have had any influence on venting the solenoid that controls air release from the piston cavity, so doesn't this point to a mechanical reason that there's a slow retract? There's enough force from the piston to overcome the bellevilles and any stiction, but maybe it's right on the cusp, so when relying entirely on spring force it drags?

Milland said:

Well, I think you said you pulled lines that would have had any influence on venting the solenoid that controls air release from the piston cavity, so doesn't this point to a mechanical reason that there's a slow retract? There's enough force from the piston to overcome the bellevilles and any stiction, but maybe it's right on the cusp, so when relying entirely on spring force it drags?

Click to expand...

That's just it!
I can't figure out how exactly it supposed to work!
If it's mechanical, it should fail with or without the hose ( hence the broken spring check )

Does it vent through the check valve Tee to the muffler on the main solenoid, or does it so through the 5PSI regulator to the precharge muffler?

Any info regarding possible checks to perform in this situation mention pulling either the pre-charge hose or the main muffler.
Precharge hose I get, but Why the main muffler?

DamnifIknow. Do you feel trying to totally bypass the system, and just plumb a 3-way manual valve into the port? Crack valve to mimic "pre-charge", full open to actuate cylinder, then vent to atmosphere to close? If no delays then it's got to be somewhere in the solenoids or related parts, yes?

I may not be helping, feel free to say so...

Did you talk to your HFO?

Today I was in and out of the shop so did not want to bother the HFO just in case they call back when I'm away, but will do tomorrow or Mo.

SeymourDumore said:

Now, after about 100 unclamp/clamp cycles I have not had any alarms, but! I did notice that when the tool is fully clamped it sits there for approx 2 seconds before the
carousel shuttle returns to home.
Ergo: I did NOT fix the problem, but I did something.

Click to expand...

Not sure if you have made any progress here yet, but the Humphrey valve works like this. The input to the valve is from the pre-charge side, output is towards the TRP piston, and the exhaust of the Humphrey valve is to the main TRP solenoid. So when the TRP returns to its "at rest" position the Humphrey valve blocks off the input and the TRP will exhaust through the exhaust port of the Humphrey valve and thus through the main TRP solenoid valve exhaust.

To your issue. You mentioned disconnecting the pre-charge line during your initial diagnosis, but did you try this after cleaning the solenoid to see if your delay goes away?
If it goes away, inspect the pre-charge solenoid valve more and verify that the pre-charge pressure is correct and that it turns off fully.

Also, watch the clamp switch in diagnostics. Watch to see if the switch is not reading right away or if the switch toggles but the delay still happens.
If the switch is not reading right away causing the delay, then I would look for a mechanical bind in the TRP return or exhaust blockage of some sort still.

One area I don't think you have addressed yet that can cause your issue are the o-rings in the TRP assembly. Mostly the small o-rings that seal the tube in the center of the assembly. I have cured a slow TRP return by replacing these or rings before, so this may be something to look at.

I don't believe Haas sells just these o-rings but I have used the o-rings from p/n: 93-3204. Now this kit is for a much older round TRP piston, but the o-rings I needed were the same and it included some of the small snap rings that fit also. However the main seal for the TRP plate will not be the same as your plate should be rectangular. Due to cost, you will probably be better off sourcing the o-rings you need locally, unfortunately I do not have any notes on the exact size you will need for that application.

Hopefully I understood your questions correctly and I hope this helps some.

Milland said:

haastec last posted on 6/13. Maybe pm him and see what his thoughts are?

Click to expand...

Thanks for the shout out, my presence has been much more sporadic for some time now, but I do pop in to the forum when I get some free time.

Thank You for chiming in Haastec!!!

haastec said:

Not sure if you have made any progress here yet, but the Humphrey valve works like this. The input to the valve is from the pre-charge side, output is towards the TRP piston, and the exhaust of the Humphrey valve is to the main TRP solenoid. So when the TRP returns to its "at rest" position the Humphrey valve blocks off the input and the TRP will exhaust through the exhaust port of the Humphrey valve and thus through the main TRP solenoid valve exhaust.

Click to expand...

OK, so do I understand correctly that the TRP, upon return to rest should be venting through the exhaust muffler ON THE MAIN SOLENOID?

If so, then would it not make sense suspecting the Humphrey vale being defective?
As it is, removal of the exhaust muffler on the main TRP solenoid, I feel little or no air escaping during the return on that posrt.
Also, with the pre-charge hose removed and the main TRP activated ( by press and hold of the tool release button ) there is a full flow of air coming through the disconnected port of the Humphrey valve.

Checked out the Humphrey website, and my guess would be that the valve acts just like a pressure sensitive OR gate.
Low pressure side active: Valve is open from LP to output.
High pressure side active: Valve is open from HP to Output.
Both sides active: Valve is open from HP to output.
Both sides inactive: Valve is open from Output to LP side, thereby venting.

haastec said:

Also, watch the clamp switch in diagnostics. Watch to see if the switch is not reading right away or if the switch toggles but the delay still happens.
If the switch is not reading right away causing the delay, then I would look for a mechanical bind in the TRP return or exhaust blockage of some sort still.

Click to expand...

Though I did not watch the switch status in diagnostics, but I do see the LED on the prox switch activating when the piston fully returns.
IOW there is no delay in the switch seeing it's target, so I do not believe the issue being electrical.
At the same time I perhaps not fully understand what you mean by "mechanical" cause.
With the precharge hose removed, the TRP returns to it's rest position in a snappy fashion, virtually without any delay.
With the hose connected however, the motion forced by the belleville washers is snappy, but the return spring portion is slow.
That to me suggests that the problem is related to inadequate TRP venting.

Now couple more things I/We have observed over the last few weeks.
Lately, when the TRP activated, it did so with a "bang". IOW the piston snapped pretty hard onto the drawbar.
Also, when the actual 130 Alarm was happening, during a manual insertion of the tool into the spindle was "funny".
The drawbar first pulled the tool in, then slowly let it back down a little bit ( maybe a 1/4" or so ), then slowly pulled it back up.
It had never dropped the tool, but certainly did not make me feel confident.

haastec said:

One area I don't think you have addressed yet that can cause your issue are the o-rings in the TRP assembly. Mostly the small o-rings that seal the tube in the center of the assembly. I have cured a slow TRP return by replacing these or rings before, so this may be something to look at.

Click to expand...

On that note, am I correct that inspection of the TRP O-rings require the removal of the whole motor/gearbox?

Again, Thank You for the help!!!

Based on your feedback, I would suspect the Humphrey valve is not operating correctly.

I don't believe you need to do so at this time yet, but you should not need to remove motor/GB assembly just to remove the TRP assembly. It should slide out from underneath the overhang just fine, although you may need to have a tool in the spindle which will lower the draw bar just enough to get it out of the way.