Extrusion Press Ladder Logic

[jeffellis1 0]

I am interviewing for a job with an extrusion press company. My next interview will involve looking at some ladder logic with a manager and answering questions. I would like to get a "head-start" by trying to find a file or something I could look at in RSLogix 500 or 5000. They also have PLC5 and some Siemens. The manager did tell me that that use alot of moving words and not so much timers anymore. If anyone has anything they could send me or know where I could find something please, any help is appreciated. Jeff jfls40@yahoo.com

[gravitar 3]

Tell us what your level of knowledge is currently.. I hope I'm not being insulting by saying this but, it sounds like perhaps you don't really have the background they're looking for.. How much time do you have before your next interview? There's a FAQ at the top of this forum that is a good place to start. If there's just some certain instructions/techniques you would like someone to explain, let us know and you're sure to get a good explanation from someone.

[TimWilborne 108]

I agree with gravitar. There are links to demos for RsLogix 500 and 5000 under the AB Faq at the top

[jeffellis1 0]

I dont mean to sound harsh or unthankful for help, but how do you guys who have responded get that I need to download a demo for rslogix or need to take a tutorial? I thought I was clear when I originally posted a request for a copy of an extrusion press program that can be opened in rslogix 500 or 5000 please send to me. period, didn't ask or need information about PLC's and my level of knowledge. I simply want to look at what I requested. I appreciate your concern but unless you know how I could obtain this thanks anyway. Jeff

[jeffellis1 0]

ps. I don't mean to offend anyone. perhaps my original email wasn't clear

[Ken Moore 23]

Your first post sounded like you were looking for any file, so you could look at some example ladder logic. You did not specify an extrusion program, thus the confusion. Many/most posters are professionals and cannot post a customers file without there permission, so I don't think you will get a working extrusion program. Most of the download section files are examples of specific techniques and a few complete projects. Sorry for any confusion, but don't be so harsh. Your vague posting caused the misunderstanding.

[TimWilborne 108]

Sorry, I miss understood your origional post. I thought by "something" you were talking about the software or basic samples of RsLogix. I did something similar to what you are looking for serveral years ago but there are many different types of extrusion presses. I would suggest you post specifics about what type of extrusion presses they use/manufacture. And think about posting it in the General Topics. It doesn't really matter what type of Plc they use, the operation will be pretty much the same Edited 10 Jan 2006 by TWControls

[Bob O 8]

Up in the AB downloads you can find a sample for a molding machine integration...Maybe this will help get you started. http://forums.mrplc.com/index.php?act=Downl...s&CODE=02&id=20 Edited 10 Jan 2006 by Bob O

[rajsiyer 7]

Gee Jeff Last year, a guy was asking me whether he could trust me to do this. Because I was quite busy, I'd turned him away. But I did during a few discussions with him think actively on almost exactly your problem. Basically, there was a hydraulic ram, forcing a red hot billet of Aluminium through the extrusion die through which the extruded aluminium section(such as for door/window frames and furniture) would emerge. Now, upon emerging through the die, the extrusion was grabbed by a pneumatic clamp which was part of a pulling trolley. The requirement here was that the trolley would have to move away at a speed which was co-ordinated with the speed at which the extrusion was happening. Understand...? Too fast and the extruded section would get stretched and be of lesser thickness than required. Too slow and the extruded section would push against the trolly and get bent. So your PLC program would have to do these tasks, with the usual safety and other interlocks. 1. Keep the die cavity temperature evenly maintained by means of a PID loop 2. Activate all the hydraulic and pneumatic cylinders in response to the control push buttions/Scada according to the Sequence of operation required. 3. There was a water spray to cool the extrusion 4. The speed of the hydraulic ram and the speed of the pulling trolly, are in a ratio depending upon the Cross section area of the extrusion. (Area of billet x pushed velocity = C.S.Area of extrusion x velocity of pulling trolly) 5. For handling die changes, your algorithm will have to keep track of which die is being used. 6. To find out the C.S.Area of any extruded section, take a piece of known length and immerse it in a measurement cylinder to obtain its volume. As you know.. Volume/ length = Area. Well.. I am giving well meaning guidelines because of the help I've myself found at MRPLC.com Hope its of some use to you. Regards, best wishes and goodluck Raj S. Iyer

[jeffellis1 0]

Very helpful indeed. I knew the overall scheme of the extrusion process but you threw added alot of clarity. I see I need to study PID loops and a couple of other things. Now if I could only find a copy of a machine program to look at the ladder logic. Jeff