Advanced Planning

Cost effective and realistic production line schedules

The Preactor APS module contains contains powerful facilities to help you balance demand against available capacity to arrive at plant and production line schedules that are cost effective and realistic.

APS enables companies to create achievable plans and schedules based on a combination of demand, manufacturing and inventory constraints. It is an essential part of any manufacturing solution, providing a baseline against which a plant should be measured.

Enhance manufacturing capabilities with useful, real time information on current activities together with advanced scheduling and quality control functions.

APS will help your company react in a timely manner to events both upstream and downstream of their position within each supply chain.

Preactor APS can provide the solution for all APS needs. Preactor systems are enabling tools, to get more from your existing applications in a number of ways.

Scheduling techniques (both event and resource focused) allow you to select and create your own production scheduling rules. Additional features allow you to add material constraints based on the Bill of Materials.

In Built Scheduling Rules

• Preferred sequence (by job attribute, setup time, process time, critical ratio)
• Minimise WIP Backwards
• Selective Bottleneck (TOC)
• Dynamic Bottleneck
• Minimise Overall Setup
• Campaigning

Preferred Sequence

This rule is data driven. Select the criteria by which the preferred sequence is created. Critical ratio is used, for example, to minimise late jobs by dynamically changing the priority of jobs based on a comparison of remaining process time with time to due date.

Minimise WIP Rules

These are sequential rules that endeavour to minimise the make-span for each job.
Minimise WIP Forward loads each job forward from the current time, locks the last operation and backwards sequences from there.
Minimise WIP Backward loads each job from its due date, locks the first operation and forward sequences from there.

Selective Bottleneck Rule

This rule is based in the Theory of Constraints (TOC) philosophy. It works by the user selecting the 'Bottleneck Resource Group'. Each order is then backward scheduled from the Due Date (less Delivery Buffer). Any operations loaded onto a bottleneck resource are offset by the Bottleneck Buffer time (defined in the Resource data table for each resource) which is designed to give some 'slack' so that any delays to operations before the bottleneck resource will not result in it being 'starved' of work.

Preactor APS then detects whether any operations in that job must start before the current time. If so, these operations are re-scheduled forwards using up some or all of the bottleneck buffer. If this is consumed then some or the entire delivery buffer may also be used up and the 'At Risk' or 'Late' flag is set.

Dynamic Bottleneck Rule

This builds on the classic selective bottleneck scheduling where the bottleneck will 'wander' depending on the current product mix that is scheduled.

Rather than pre-processing your orders to determine a single bottleneck, the Dynamic Bottleneck Rule calculates the bottleneck individually for each job. Operations 'upstream' of the bottleneck are then backward sequenced, inserting a resource buffer like the Selective Bottleneck Rule.

Minimise Overall Setup Rule

This is similar to the Preferred Sequence Rule but is focused purely on minimising the setup or changeover time on resources.

In the Preferred Sequence Rule as each resource becomes idle it selects the next operation to load based on the preferred sequence criteria in the resource database, without any consideration for other resources that could also be used.
So, provided one or more operations can be run on the resource and they lay within the 'Look Ahead Window', one of them will be scheduled based on the preferred sequence.

In the Minimise Overall Setup Rule, consideration is made across all resources able to run the operation even if they are still busy. The rule does not use the preferred sequence criteria in the resource database but it does use the 'Look Ahead Window' to decide whether an operation should be available to be scheduled in the same way as the Preferred Sequence Rule.