Digital Production Planning for Machinery Manufacturers
Fully Automated Production Planning
For some years now the topics of Industrie 4.0, Smart Factory, AI, etc. have been discussed, though most German mid- to large-sized companies use Excel to plan for their production; many believe that a supplementary module to the ERP system, such as an MES, constitutes the solution to achieving Lean-manufacturing – only to realize then reliance on manual planning with Excel persists.
The production planning department is the brain and backbone of the company, because all other organs are geared towards fulfilling their tasks just-in-time according to the production plan. It follows that an inaccurate production plan results in very expensive waste due to inefficiency throughout the company.
Common planning software offers consist of a fragmented portfolio of functionally independent applications which hardly allow for seamless, integrated use. It is imperative for Industrie 4.0 that fully automatic APS/SCP software is employed, which enable continuous, horizontal, and cross-functional orchestration of all processes. Asprova is such a system, which uses highly advanced algorithms to meet the highest requirements and more, providing maximum added value.
Initial Situation at the GEBHARDT Company
The ERP system in-use at GEBHARDT GmbH is SAP. Up to the introduction of Asprova APS in 2016 planning needed to be done in Excel, a manual planning and control process.
Most of the product is manufactured in-house. To draw up an optimal sequence plan for the complicated manufacturing processes (which include laser cutting, punching, bending, turning, milling, welding, pre- and final-assembly, electric assembly, etc.) which includes outsourced processes (galvanizing and varnishing) is impossible to do manually with Excel. To get to a passable plan takes several days’ worth of man hours, as opposed to a few minutes with an APS system! But the challenges GEBHARDT faced at that point were very concerning:
- All planning know-how resides inside of the heads of production managers.
- Complexity of the manufacturing process increases continuously as the product portfolio keeps growing and project numbers grow!
- The start date for manufacturing order is established according to individual experience, which results in push-production. Start dates need to be adjusted constantly on call.
- Production processes of individual components, not being in-sync, results in long lead times.
- Much stagnation results in great inventory, especially for intermediate products.
The GEBHARDT Company enjoys continuous growth. Increasing complexity in planning due to greatly increasing order numbers meant that an optimal planning method needed to be found – quickly. To improve the manufacturing process’ efficiency, many requirements were denoted as to what the next-generation planning system must be capable of.
Mapping entirely GEBHARDT’s process-specific rules and restrictions for all resources, products, etc. has been a challenge, of which some aspects are;
- Multi-level finite-capacity planning – main resource and sub resource capacity must be considered simultaneously for every single resource during scheduling.
- Automation of selection of alternative resources
- Getting parallel processes and merging processes all in sync with each other.
- Consideration and availability of raw materials and work-in-progress parts
- Consideration and availability of workers (individual shift calendar, days off)
- Outsourced manufacturing
The most important aspect of planning software is its ability to map reality completely. This includes all properties for products, processes, process rules and process restrictions, and even planning restrictions. This is because if even a minor property is not mapped or mapped incorrectly, consistency throughout the production plan becomes disproportionately affected, as everything is intricately intertwined. Unrealistic plan are output which are not feasible to carry out, and one must resort to manual planning.
The Most Important Asprova Setting/Functions for GEBHARDT
A project kick-off workshop commenced during January of 2016, after which the interface settings for communication with SAP were completed. The system went live at the beginning of July of 2016 (including writeback of newly issued manufacturing order from Asprova in SAP).
Mapping all processes, process rules and process restrictions to a degree of 100 % with Asprova:
- Abilities/capacity and restrictions for each production resource (machines, workspaces, workers)
- A matrix for bending machines specifies the type of sheet metal that may be processed on specific machines.
- Depending on device type, certain assembly spaces are available. SAP purports the workspace groups; Asprova selects the optimal assembly area.
- Process times, changeover times, and waiting times between processes with individual rules with minimal data maintenance.
- 20 outsourced manufacturers (for galvanizing, varnishing, and more): Every outsourced manufacturing processes has its individual lead time. Asprova automatically calculates pickup and return delivery dates.
- If internal production capacities are overloaded, the planer decide which orders (components) are to be outsourced according to simulation.
Consideration of material inventories:
- The final product can consist of up to 100,000 components. Asprova plans and considers current inventories, inventory fluctuations, and material income dates.
- Asprova automatically links individual components, parts with individual manufacturing orders, thereby enabling One-Piece-Flow with subassembly components.
- Asprova plans the timing (completion and demand) for all intermediate components.
- Material availability check based on BOM (material requirements) and inventories, orders, order requirements (replenishment)
- Remaining quantity in BOM
- Booked quantity of current inventory
- Order with quantity with delivery date that has been confirmed by the supplier
- Order requirements with quantity and desired delivery date
- For every process Asprova calculates the earliest possible start date. Process start time and date is directly dependent on material availability.
- Consideration of material handling time
- Missing parts list: If no inventory, orders, or order requests for replenishment exist, or if they are late, then they become listed in a pivot table – per material number or per order (in day- or week roster). Asprova issues a demand due date for the missing parts.
Sequence optimization in areas bending and turning:
- Changeover matrix set in Asprova
- Optimization of sequence plan to minimize changeover times regarding timing as well as alternative bending and turning machines.
Planning logic and dispatch rules:
- Detailed and complicated dispatch rules can be established for every manufacturing order, resource, customer, etc. individually in Asprova.
- Sorting for multiple planning loops with varying rules for sequencing (such as post-processing orders first; priority for delivery date thereafter; and finally manufacturing orders-to-stock)
- Component manufacturing etc. according to sequence and due dates of assembly at the end-customer
- Asprova links sub-assembly parts with the assembly order. The delivery date of the customer order becomes heritage in all sub-order, influencing the sequence of the mechanical manufacturing area and assembly for optimization (pre- / final- / electric).
Interface to SAP:
- Once-per-day data is imported into Asprova from SAP (differential import): customer orders, plan- and manufacturing orders, work plans, BOMs, material master data, material inventories, material orders, work progression on the shop floor, etc.)
Rough planning run:
- Planning preparation; operations are created and all order become linked with each other
- Orders for which progress feedback has been reported and fixed operations are assigned first.
Planning master orders and the assembly
- The order dispatch rules determines operations sorting –
- Forward with finite capacity if material is available up to the delivery date; otherwise forward at an earlier date.
- If planned too early, adjust backwards.
Planning sub-assembly components, adjusting the assembly
- Sub-assembly components are sorted according to the order head.
- Order operation in the mechanical manufacturing area are sorted once more according to traits such as sheet metal parameter, CNC programs (withing start day of previous assignment)
- Operations of non-bottleneck resource (laser cutting, electrical workshop, outsourced manufacturing) as assigned once more – backwards towards the start date of the next process/operations/manufacturing orders. Depending on the start time of the downstream process other operations may be pulled closer. (A 1- to 3-day buffer is in place.)
KPI Plan Evaluation
Results of scheduling with Asprova:
- Enabled doubling of turnover through the past four years via 100 % increased output while making no changes to the production area. The key has been lead time minimization.
- Highly realistic and feasible sequence plans for every resource.
- Process snychronization
- Consideration of material availability in planning
- Daily update of the plan, which contains more than 30,000 manufacturing orders spanning a planning horizon of 24 months in advance, in under two minutes.
- Order status visualization of individual orders 24 months in advance. (Order-Gantt-Chart, Resource-Gantt-Chart, table for sequence manufacturing, capacity load diagram, and more)
- Reliable delivery dates can be forwarded to the customer with confidence.
The GEBHARDT Conveyor Technology Corporation in Sinsheim, Baden-Wurttemberg State provides large-scale internal logistics system solutions. Their product portfolio includes goods lifts, containers, variable plate transport systems, robotic transportation systems as well as complete storage systems for wholesale companies, auto makers, and the like. GEBHARDT’s strength further lies in their delivery of software, electronics, robots, and other facilities – all from a single source.
The author, Keiji FUJII, is the CEO and shareholder of the Asprova AG.