Trueblood 30-ton help needed

[Chuck H]

I acquired a Trueblood TB 30B-1.1 screw-type molding machine ... basically free except for the cost of trucking it to my home.

It is controlled by an Allan Bradley SLC-503 and an Allan Bradley 550 PanelView operators panel.

Part of my problem is that I have electrical and hydraulic diagrams but I do not know how the machine is supposed to act or how to set the operating parameters. I do not have a "setup" or "operator's" manual. I only have experience with a much older ram-type machine.

I know that it is designed to close the clamp at low speed, low pressure until it reaches a certain point (to check for obstructions) and after that build to full clamping force.

On the PanelView the screen for the clamp settings looks like this:


My understanding is that the "Min 10" in the upper right says that the hyd pump will be shut down if the machine has been idle for 10 minutes.

Note that the current "actual" position is -0.003. When this photo was taken, the clamp had fallen slowly as far down as it would go.

All positions referenced below (I assume) are distances "up" from this position. I don't know what the "Mach. Cycle 28.91" is other than perhaps what the calculated cycle time would be with these parameters?

All values below were in the machine but are suspect because the backup battery was down to 0.1 volts (from 3v) when I got the machine.

When I press manual "Clamp Open", I assume:

* "Clamp Open" is the final position (upper most) that the clamp will move to when I manually command it to open.

* "Slow Open" .. the clamp will open slowly after reaching this point during the open cycle to the final "Clamp Open" height using a flow rate of 90% and a pressure of 900 psi.

* "Fast Open" .. the clamp will open quickly after reaching this point during the open cycle to the final "Slow Open" height using a flow rate of 100% and a pressure of 1500 psi.


When I press manual "Clamp Close", I assume:

* The clamp will fall quickly using a flow of 100% and a pressure of 1500 psi for a maximum of 5 seconds to the "Slow Close1" position and fault if "Slow Close1" is not reached in that time (obstruction).

* After reaching "Slow Close1" it will close using 45% flow at 1000 psi to the "Slow Close2" position for a maximum of 16 seconds and fault if "Slow Close2" is not reached in that time (obstruction).

* After reaching "Slow Close2" it will close using 3% flow at 821 psi until it reaches the final close position of "Clamp Close". Note that the position shown (7.280") seems wrong because it is above Slow Close1. The flow and pressure could be right, I don't know.

* The current "Clamp Close" position does not seem correct in that it is only 0.020" from the maximum downward position and I doubt that a mold would have been this close to that dimension (BTW at the current position shown of -0.003, bottom of the stroke, the clamp is about 5.75" above the rotary table).

In my trials I have had the following symptoms of something going wrong:

* When I first try things in a session Clamp Open seems to work except that, if I hold it, the clamp seems to oscillate slowly about an inch at the top of the stroke. I assume that this is because the "counterbalance" check-valve on the Clamp valve body group is sticking open.

* If the clamp is at the top of its stroke and i release the Clamp Open buttons, the clamp slowly falls (about 1" per second). I take this as another indication that the counterbalance check-valve is not closing.

* If, while falling, I quickly press the Clamp Close buttons, the clamp will be driven down. After that, the Clamp Open seems to work better indicating to me that the counterbalance check-valve was forced to seat and/or become unstuck.

* If I hold the Clamp Close sufficiently long enough, the prefill valve closes and the clamp builds to a gauge pressure of 3,000 psi.

Do my assumptions above seem reasonable?

Is anyone familiar with Trueblood machines?

Are these parameters fairly standard to the industry?

Does anyone know where I can get a "setup" manual for this machine? I have searched the Internet but I can't find "Trueblood" (a division of PH Group) or a follow-on corporation I could contact for information.

Is it normal for the clamp to build to maximum clamping force even though it might not be needed for a given mold?

Does anyone know what Allan Bradley (now Rockwell) Rslogix software I can use to upload the SLC503 program to my PC? The latest version does not seem to understand SLC50x PLCs.

I have more questions but I'll stop there for now.

Thanks in advance for any guidance you might be able to offer. I can provide a hydraulic diagram if desired. I'm a retired EE by education but spent my whole work life in software development.

Regards,

Chuck Hackett