MES functionality: production scheduling

Introduction

Production scheduling plays a crucial role in the efficient management of manufacturing operations. Manufacturing Execution Systems (MES) serve as a vital tool in this process, offering features that enhance visibility, control, and flexibility.

The initial production order schedule is generated in Enterprise Resource Planning (ERP), which looks at the customer demand and existing stock levels to determine which semi-finished and finished goods need to be made. ERP typically does some level of prioritisation of production orders, these orders are then transferred to MES.

Once the production orders are in MES, further tweaking of the schedule can be performed in order to fine-tune the sequence of orders, and the equipment that the orders are scheduled to run on. Different MES systems have varying levels of sophistication around production scheduling.

In some scenarios, there may be complex scheduling requirements. These situations usually call for a dedicated Advance Planning and Scheduling (APS) tool to manage the more advanced scheduling algorithms. These systems can be far more sophisticated around complex scheduling requirements.

Production Scheduling in MES

MES acts as a bridge between ERP and the shop floor. MES facilitates the smooth flow of information by downloading production orders from the ERP, including essential data such as routings and bill of materials (BOMs). This integration ensures that the production schedule is accurately aligned with the required resources and materials.

One of the key advantages of MES is the ability to provide real-time visibility into the production schedule. Production schedulers can access the schedule, review its details, and make necessary adjustments as required. This dynamic view of the schedule empowers schedulers to optimise resource utilisation, balance workloads, and ensure timely order fulfilment. The scheduler then releases approved orders to production, giving operators visibility of the upcoming orders, and allowing other departments such as maintenance and tooling to plan appropriately.

MES production scheduling extends its benefits beyond production schedulers to operators on the shop floor. By providing operators with visibility into the schedule, they can proactively plan and execute their tasks. Operators can easily access work instructions, prioritise their production orders, and effectively manage their workload. This visibility fosters collaboration, minimises errors, and enables quick responses to changes or unexpected events.

Key Features of MES Production Scheduling

Let's examine some of the key scheduling features in MES application.

Production Order Download from ERP

MES retrieves production orders from the ERP system, including important information like routings and BOMs. This ensures that the production schedule aligns with the overall manufacturing requirements.

ERP generates Production Orders based on customer demand, or based on stock levels. A production order is synonymous with a "Works Order", or a "Manufacturing Order". You will hear these terms used interchangeably across products, and industries.

Schedule Viewing and Adjustment

MES allows production schedulers to view the schedule in real-time and make necessary adjustments. Whether it's modifying order sequences, assigning resources, or accommodating changes, schedulers have the flexibility to optimise the schedule for maximum efficiency. Alternatively, the sequence of orders can be locked and enforced, preventing operators from executing out of sequence.

Resource Allocation

MES handles allocation of resources to production orders, such as equipment, personnel, materials, and tooling. Resources can only be planned to be used on a single order at a time. For example, a tool can only be used by one production order at any given moment, later it can be used in another production order. MES handles the resource allocation and prevents conflicts in the schedule.

Production Order Release to Manufacturing

Once the schedule is finalised, MES releases production orders to the shop floor, providing operators with clear visibility of their tasks, priorities, and any specific instructions associated with each order. This enables smooth execution and facilitates efficient workflow management. Communication is improved, and changes to the schedule can be seen by operators in real-time, without the need for new paperwork to be manually distributed.

ERP, APS and MES: who does what

It helps to be clear about the roles:

• ERP creates production orders from demand and stock levels, with an initial plan that usually rests on simplified capacity assumptions.
• MES/MOM sequences and executes that plan on the shopfloor, allows last-minute adjustments, and feeds back real progress.
• APS (advanced planning and scheduling) adds detailed, constraint-based scheduling when the scheduling problem itself gets hard.

Do you need an APS?

Often, no. For many manufacturers ERP plus MES/MOM is enough, especially where production is stable, demand is predictable and changeovers don't drive the sequence. An APS earns its place when sequencing itself becomes the hard problem: shared bottlenecks, sequence-dependent changeovers and lots of orders competing for the same resources. I go through the signs, and the options for connecting ERP, APS and MES/MOM, in ERP, APS and MES scheduling: the plan versus the shift.

The real value is a live schedule. A printed schedule is out of date before the ink is dry. When the schedule reflects what's actually happening, it adjusts when a machine goes down, and the planner knows immediately rather than at the end of the shift.

Benefits of MES Production Scheduling

Implementing MES production scheduling brings numerous benefits to manufacturing businesses.

Enhanced Visibility and Control

MES provides real-time visibility into the production schedule, allowing for better monitoring, control, and decision-making. This visibility empowers production schedulers and operators to proactively address challenges and ensure smooth operations. Operators get real-time visibility of any updates to the schedule, and schedulers get real-time updates to delays on the shopfloor.

Improved Efficiency and Productivity

By optimising resource utilisation, balancing workloads, and minimising downtime, MES enhances overall operational efficiency and productivity. It enables manufacturers to achieve higher output with fewer resources.

Timely Order Fulfilment and Customer Satisfaction

With MES, manufacturers can meet delivery commitments, reduce lead times, and improve on-time order fulfilment. This leads to enhanced customer satisfaction and fosters strong relationships throughout the supply chain.

Agility and Adaptability

MES equips manufacturing businesses with the agility to respond to changes in demand, accommodate rush orders, and adapt to unforeseen disruptions. This flexibility ensures that the production process remains responsive and resilient.

Conclusion

Production scheduling within MES enhances the way manufacturing businesses manage their operations. By serving as a link between ERP systems and the shopfloor, MES keeps data integrated and aligns of resources with the production schedule. The real-time visibility and adjustment capabilities empower production schedulers to optimise efficiency and ensure timely order fulfilment.

Production scheduling functionality varies enormously between MES systems. Be careful, because some MES providers have a separate application for scheduling, rather than it being built into the core MES application. Other MES applications partner with 3rd party scheduling tools. In both of these cases, interfaces will be required to transfer schedule changes, which can impact the reactivity and real-time benefits MES can otherwise achieve.

This article is part of the MES functionality series. Related: The smart factory tech stack.