This article details the usage of the Tailout input to the XL200 Series machine controller. Proper use of this input keeps scrap tracking accurate when loading and unloading coils on a roll former. It minimizes the amount of paperwork required by the Machine Operator for the purpose of recording scrap material. The Tailout input is also a critical component in the Coil Verification functionality in Eclipse Production Management Software.
Tailout is an input to the XL200 controller. This input is designed to come from a material sensing device located on the roll former, near the material encoder. The input serves four functions in the controller:
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Reference of New Coil to Avoid Erroneous Reporting of Startup Scrap
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Automatic Prompt of Load/Unload Coil
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Automatic Halt at End of Coil
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Proper Reporting of Scrap at End of Coil
Reference of New Coil
Tracking startup and end-of-coil scrap on each coil is important from the perspective of Purchasing and Production efficiency tracking. For many companies, the scrap generated at coil change usually accounts for the highest percentage of scrap from the entire process. When using the XL200 controller and Eclipse, the equipment must be setup properly with a Tailout sensor and the machine controller must have accurate settings. Otherwise, the scrap reports generated for Production and Purchasing can be wildly inaccurate.
In most applications, when the Operator loads a new coil he must jog some amount of material past the cutoff and perform a standing cut. The outer wrap of the coil might be damaged due to shipping and handling, or the leading edge of the material must be squared to the cutoff tooling to produce the first good part. This function also serves to reference the cutoff to the material for the length control system.
Let’s examine what happens when the operator loads a new coil onto a post cut roll forming line:
Example 1
For the purpose of this example, we’ll assume the coil is in pristine condition and that the Operator simply needs to square up the leading edge of the coil. The amount of startup scrap should be minimal. We’ll begin by examining what happens on a machine that does not have a Tailout sensor mounted. The machine is empty (no material loaded), and the XL200 currently reports 0.000” past the shear. Note the physical distance from the encoder (the device that measures material) to the cutoff at home position (120” or 10’).
Post Cut Roll Former Ready for New Coil
The Operator begins by loading a new coil. He threads the leading edge of the coil into the first set of rolls on the roll former, and then he jogs the material through the machine. This is often called “thread up”.
New Coil Partially Threaded Through Roll Former
As previously stated, this coil was in excellent condition, so the Operator only needs to thread a few inches of material past the cutoff blade in order to square up the leading edge. In this case, he’ll jog 5” past the cutoff.
The problem in this scenario is when the Operator was threading material into the roll former the control system was powered ON along with the rest of the machine. As the material flowed under the encoder wheel (measuring device), the wheel was turning. So, by the time the operator jogs 5” past the cutoff, the XL200 controller has seen 125” of material pass the encoder, and it reports that amount on the screen.
Reporting Error Due to Encoder Placement Distance
When the Operator performs a Manual Shear operation on the material, the XL200 automatically reports any material past the cutoff as scrap to Eclipse – in this case, 125” of scrap. Since this machine did not have a sensor to detect the presence of the material, the XL200 had no way of knowing how much material was actually scrapped. It erroneously reported 10’ more scrap than was actually produced from the beginning of the coil.
The situation described in Example 1 is precisely the reason the XL200 has a Tailout input, as well as a parameter called Shear to Encoder Distance. Many users mistakenly believe the Shear to Encoder Distance is somehow used to calculate good part distances. This is unnecessary. The physical distance from the encoder to the shear (cutoff) should be a straight line, usually consisting of formed material. Once the Operator performs a Manual Shear, the XL200 references the cutoff to the material. Any amount of material that passes the cutoff tooling at a given point in time will be exactly the same amount of material that passes the encoder at the same point in time.
The only purpose of the Shear to Encoder Distance is so the XL200 can accurately report scrap to Eclipse during coil changes. Now, let’s examine what happens during a coil change when a Tailout sensor is properly mounted and the Shear to Encoder Distance configured:
Example 2
As in Example 1, the Operator has partially threaded a new coil through the roll former. This time, as soon as the leading edge of the coil reaches the encoder, it also triggers a Tailout sensor mounted at the vertical centerline of the encoder wheel. The placement of the sensor with regard to the vertical centerline of the encoder wheel is critical for accurate scrap reporting.
Tailout Sensor Triggered as Material is Threaded
As soon as the sensor detects the leading edge of the material, two things happen at the XL200 controller; the length past the shear references to a negative distance equal to the Shear to Encoder Distance, and the controller automatically prompts the Operator for the new coil number.
Controller Referenced to Encoder Distance and Operator Prompted for New Coil
As the Operator continues to jog material forward through the roll former, the count on the controller screen should become more positive as the leading edge approaches the cutoff. When he jogs the leading edge 5” past the cutoff tool, the controller will accurately report 5”.
After threading the roll former, the Operator will stand before the XL200 to perform the Manual Shear operation to trim the leading edge of the coil. This time, he has a visual prompt on the screen requesting the new coil inventory number. If the Operator attempts to ignore the prompt, the XL200 software enforces the procedure and will not allow a Manual Shear until the new coil’s number is entered. This prevents scrap from a new coil from being counted against the last coil.
Software Enforcement of Procedure
The Tailout input, in conjunction with the Shear to Encoder Distance, is used to correct the starting scrap on a new coil. The more accurate the distance measured from the point where the encoder wheel contacts the material to the back of the cutoff (shear blade), the more accurate the system will be when reporting scrap. Thus, the Tailout sensor should be mounted at the same vertical centerline as the encoder wheel.
Automatic Prompt of Load/Unload Coil
As seen in a preceding example (Example 2), one of the functions of the Tailout sensor is to automatically prompt a Machine Operator for a coil inventory number when loading a new coil. This allows Eclipse to accurately report raw material usage with regards to Coil Numbers, Order Numbers, Operator and machine performance, vendor performance, etc.
It also supports the Coil Verification feature within the Eclipse/XL200 system. When this feature is implemented, the system reports back to the operator on the current footage remaining on coils loaded, so the Operator can quickly decide if he has enough material on-hand for a batch of production. Software rules also allow management to enforce policies ensuring the correct raw material is used for every order.
The first time a XL200 controller receives the Tailout input (after a new startup, as a replacement unit, after memory clear), the Machine Operator is presented with the Load New Coil window the first time he loads a coil onto the roll former:
Automatic Prompt to Load New Coil
Once the operator enters the inventory Coil Number, the XL200 passes the number up to Eclipse to verify the coil exists in the system records. If it does not, the operator is presented with a warning message, indicating something must be done to correct the accounting error, or that the Coil Number was improperly entered:
Coil Number Entered Does Not Match Inventory
Once the inventory is corrected or the correct coil number is entered, the system provides feedback to the Operator regarding the current coil’s raw material, as well as the raw material needs of the production schedule:
Operator Feedback from Eclipse Regarding Production Needs/Availability
In the example above, the Operator is presented with a message that indeed, the coil loaded exists in the company inventory. Additionally, he’s notified that the amount of material remaining on the coil is more than sufficient to meet the needs of scheduled production.
If the Length to run or the Additional length scheduled exceeds the Coil length remaining someone could be notified to stage additional coils of the same material type, or other decisions could be made regarding the practicality of trying to complete the scheduled production with what’s on-hand at the time.
So far, we’ve examined the process from the perspective of a first-time coil load. When a coil change is required, subsequent prompts from the XL200 first require the Operator to notify the system whether the last coil loaded was returned to inventory, or if it was completely consumed:
Unload Current Coil
Once the Operator tells the system the state of the last coil, he’s once again presented with the Load New Coil prompt. Depending on the Operator’s selection, Eclipse will update coil totals (and print a new coil ticket if this feature is used), or it will tabulate the final totals for the coil, zero its remaining footage, and tally any differences between the estimated length and the actual length consumed.
There are additional menus and options connected to the Coil Verification feature, but those are better described elsewhere in a separate, more focused document.
Automatic Halt
The XL200 controller can only cut or punch in automatic if the material is currently moving under the encoder wheel. Once the last inch of material has flowed past the encoder wheel, the XL200 can no longer track punch or shear targets.
At the end of a coil (or at the Coil Endpoint) when the trailing edge of the material passes the Tailout sensor, the sensor toggles to its “On” position and the controller automatically exits out of Run mode. At this point, no more encoder motion is accepted by the controller - if the machine has “tailed out”, then there’s no material to track. This is another reason why the mounting location of the Tailout sensor is critical. The more material left in the machine, the more hand manipulation of the last portion of the coil that will be required by the Operator.
Reporting Scrap at End of Coil
At the end of a coil, some amount of scrap is typically unavoidable; material might be of poor quality, the controller cannot automatically cut the final length, etc. Because of these issues, when the XL200 controller receives the Tailout input, it automatically reports any material past the shear plus the Shear to Encoder Distance as scrap to Eclipse. This happens without operator intervention.
Let’s examine a coil Tailout condition using the same machine as in Example 2:
Example 3
When the tail end of the material is pulled through the roll former and passes the Tailout sensor, the XL200 halts the line, and immediately reports the remaining material in the machine as scrap to Eclipse. In this case, the machine stopped with exactly 40” past the cutoff. Additionally, it also had the 120” of material from the encoder to the entry side of the cutoff.
Coil Tailout
At the moment of Tailout, the XL200 automatically reports 160” inches of scrap to Eclipse on the current coil. If the remaining material is truly unusable, then the Operator merely empties the machine, and threads the next coil. All accounting has already been handled by the Eclipse/XL200 system.
Often, the remaining footage on a roll former can be hand-manipulated by the Operator in order to recover at least one last, good part from the coil. If this is the case, the operator simply hand-positions the remaining material so he can perform a Manual Shear operation to manually cut the last good piece(s).
Once this is complete, the operator should use the F5 - Decrease Quantity feature on the Status menu to alert the XL200 as to the number of good pieces he was able to recover from scrap. Decrease Quantity not only corrects the current “Done” part quantity, but it automatically alerts Eclipse to take that length x quantity out of scrap for the current coil and add it back to “good footage”.
Whatever unusable length remains has already been accounted in the scrap total. All accounting is handled within Eclipse, without the need to collect paperwork from the Operator.
Summary
Coil changes in roll forming processes are typically the most scrap intensive part of the operation. Accurate tracking of scrap and coil inventory are important to Purchasing/Accounting and Production.
A Tailout sensor, coupled with the XL200 machine controller and Eclipse Production Management Software, can provide a powerful tool to automate coil data entry and provide accurate scrap tracking.
The Tailout input on the XL200 machine controller performs several critical functions pertaining to coil changes, and is integral to the Coil Verification feature within the Eclipse/XL200 system.
Diligent Operator training combined with software enforcement of policies leads to accurate accounting and greater automation within the system. This leads to the elimination of wasted time for the Operator and paperwork for the Production floor, as well as the office.