Processing Large Cut Sheets on Shearline type devices

When processing cut sheets on Shearline type devices several considerations must be made that affect the performance of the optimising engine.

While it is tempting to simply select all the bar that is scheduled against all manifests for a large time slot and attempt optimisation for a 15 tonne load thereby reducing offcuts, this will have several drawbacks.

For this example, we have selected all manifests for the day and isolated the N24 work for the Auto Shear. This is 15 tonnes of bar covering some 450 tags with 16K items.

The first part of the optimising calculation will attempt to allocate the best cut from the selected source stocks (In this case 12 and 9 metre lengths)

This part of the processing is done by a shared license on a remote server hosted in Bestbar's Cloud Data centre. The more bars there are to cut, the longer the calculation will take. The more refined the optimisation (i.e. better use of offcuts) and the selection of source bar will also affect the time taken to calculate the cut cycles.

In this case the optimisation calculation took around 15 minutes and produced 50kg of offcut and while an impressive result is not realistic.

The second part of the optimisation involves placing the tags cut into the output bays of the shearline.

This is normally restricted to around 6 output bays 12 metres long. some of these bays will be reserved for straight bar only while others will be reserved for the benders that can load the bar from that bay. Depending on the number of parts required for each bay this may also take some time. 

A warning at the end of the calculation displayed "There is too much cut bar in the run" and "There is too much bent bar in the run" The short of this is to advise that it is not possible to process this cut sheet and drop the cut bar into the bays necessary for the benders to be able to process the bar successfully and is unusable from a practical perspective.

Splitting Cut Sheet results

If a large cut is not optional, there exists a function once the initial cut to is calculated to split the results into smaller cut sheets.

Right click the results grid and select "Split cut sheet". This will force an alternative calculation on the results to break it down into smaller cut sheets if possible. In this instance 3 cut sheets were derived and while two are smaller and usable, the second cut sheet still has too many articles on it and cannot be successfully processed.

If the cut sheet is split, when printed the 3 cut sheets will be processed separately and in order and relative tags for only the items on that  printed at the end  of each cut sheet print out.

To produce more meaningful result's it is prefereable to keep the number items selected as small as possible and target production based on either a ssmaller selection of manifests or on a time basis from the expected delivery deadlines.

Disabling Optimisation

If larger cuts must be used and optimisation is not critical it can be disabled by setting the shearlines out put option to Offcoil device.

Right click the device in the Production lines grid and select Maintain Device.

Set the Off-Coil machine checkbox and save the changes.

Cut sheets not processed will not be optimised and stock usage will not be calculated but results will generate quickly (As neither of the optimisation or stock minimisation calculations will be performed).

This feature may be altered on an ad-hoc basis as required.