A company in Shenzhen (whose name is withheld at the request of the customer) produces small household appliances. Most of the product components require injection molding and come in various shapes and colors. The semi-finished components are processed and then assembled. The basic situation of customers is as follows:
- More than 100 injection molding machines of various types
- Many product varieties and many molds
- Molds and products have a many-to-many relationship
- The same mold can produce products of multiple colors
- Products using the same mold may use different inserts
- Some products have split molds, that is, several products share one mold
Before importing PlanMate, scheduling was done manually, which had the following problems:
- The management of molds is irregular. The corresponding relationship between products and molds, the number of times the molds are used, and the current status are all managed manually, often in a state of chaos.
- The production schedule can only schedule the next 24 hours, and cannot schedule plans for a few days later.
- Orders cannot be given a definite delivery date and are often delayed.
- Color switching and mold switching are not optimized, and efficiency cannot be guaranteed.
- It is necessary to modify the plan when mold failure or order changes occur, and it is difficult to modify the plan
Improvements after system introduction:
By importing PlanMate, customers have greatly improved in terms of equipment utilization efficiency and delivery time management.
- Standardized and mandatory data maintenance: In the manual scheduling mode, there are multiple production managers, each of whom is responsible for a part of the equipment. Each person only maintains the data they need. There is no unified data maintenance management. When the production manager asks for leave or resigns time, it will cause scheduling confusion. By importing PlanMate, due to the mandatory requirements of the system, a dedicated person is responsible for data management. Products, molds, colors, and production process parameters are all accurately defined. This avoids scheduling errors due to data errors and avoids confusion due to personnel changes. .
- Save manpower and switch from multi-person scheduling to automatic system scheduling, requiring only one person to operate. Scheduling is fast.
- From scheduling only one day to scheduling all work orders, short-term scheduling is 1-2 weeks, which is used for actual production in the workshop. Long-term 3-6 month plan for order evaluation and delivery confirmation, equipment load evaluation. Through accurate confirmation of order delivery dates, order delays are reduced and customer satisfaction is increased.
- Quickly respond to changes in plans and quickly rearrange plans when equipment fails or needs change.
- Mold switching and color changes are optimized during scheduling, reducing unnecessary switching and reducing switching costs. By changing the shades of the same color system, dark and light colors are scheduled separately to avoid unreasonable color changes and reduce the waste of time and color materials caused by color switching.
Solution points:
- Demand splitting: Some orders are placed on a monthly basis and the volume is relatively large. If they are not split, they will require continuous production for many days, which will affect the production of other orders.
Solution: After conducting capacity analysis on daily delivery orders, based on the equipment load of each week, split the monthly orders into weeks according to the equipment load to balance the load rate of each week. This part is implemented in the custom module PlugIn
- Product molding: A mold is composed of several products, with acupuncture points opened separately, and they must be assembled together for production during scheduling.
Solution: Because the demand time and demand of the product may be different, we designed a matching deduction function to allow the system to match and deduct other material numbers in chronological order according to the product with the largest demand, retaining the largest demand product work orders, and make forward and backward adjustments according to the demand time of the material number, so that production can meet the delivery requirements of all work orders. This part is implemented in the custom module PlugIn.
- Equipment selection: Usually there are several types of machines available for a mold. When the mold ejection time remains unchanged, machines with lower tonnage are preferred to reduce production costs.
Solution: In PlanMate’s model, multiple devices can be selected for each mold, and the priority of each device can be different. After the equipment selection priority is defined in the model, the system will prioritize equipment with higher priority in automatic scheduling.
- Optimization of combined production and switchover
Solution: For work orders with the same product and close demand times, the same product will be scheduled continuously as long as the delivery date is met. Products using the same mold will be produced continuously when color switching is allowed, reducing mold switching.
- Color switching
Solution: Set the time and cost for color switching, and define prohibited switching (such as black to white), then the system will automatically optimize the color switching during scheduling and avoid prohibited colors.
- Multiple mold selection: Some products with large output will have multiple molds, and system scheduling requires mold selection.
Solution: If the product has only one mold, the schedule will not allow two machines to be produced at the same time. If there is more than one mold available for the product, the mold selection priority must be defined in the model, and the system will select the mold according to the priority during scheduling. If using only one mold would exceed the delivery date, the system will use multiple molds for production at the same time.
- Condition and maintenance of the mold: The mold requires regular maintenance and cannot be used during this period.
Solution: PlanMate’s model allows auxiliary resources to have different quantities in different time ranges. If the mold quantity is defined as 0 during the unavailable time period, then this mold will not be used in this time schedule.
- Actual production progress: After scheduling, the actual production progress needs to be obtained for plan tracking and adjustment.
Solution: The factory has not imported the MES system. Before each shift, the work report of this shift is entered. Planmate reads the work report and updates the work progress. The production management adjusts the plan according to the actual progress.
- Order adjustments and plan modifications
Solution: Under normal circumstances, download new work orders every day and run a schedule. Some work orders will be completed in the current plan, and some new work orders will be added.
- Production schedule report
Solution: The production schedule report is customized using VBA in Excel. The format is flexible and easy to expand. The output report can be distributed as an independent file and can be edited and modified. Reports mainly include:- Production planning that splits tasks by shift for use on the shop floor
- Delivery date reporting for all work orders (early or late times, WIP, etc.)
- Product daily output plan
- Material Requirements Planning
- Inventory allocation plan
Customer ERP: Oracle
Interface implementation method: The project interface implements data exchange through report import and export.
- Export data from ERP to PlanMateAPS: work order list, customer demand, inventory, and material issue list;
- PlanMate exports to ERP: work order start date, work order split list, work order merge list;
Customer question point 1:
For the PCBs used in the manufacturing of cameras by Polytech, before the introduction of PlanMate, the material inventory level remained high. This is due to the work order management method adopted by the factory.
Customer orders vary from large to small. Some customers place long-term orders on a monthly basis, while some product orders are very small. When starting work orders in the factory, long-term orders are billed according to fixed quantity requirements, for example, each work order for small plates is 5,000, and each work order for large plates is 3,000. For small orders, refer to the quantity and start date of the customer order, and set the demand time close to Small orders merged.
This method of starting work orders seems reasonable at first. The problem is that customer orders are constantly changing. When the quantity is adjusted or the time changes, the quantity of work orders and the start date will seriously mismatch the customer needs. Such as the following situation:
- If the customer adjusts the demand, 1,000 of the work order 3 corresponding to January demand will be advanced as a whole, and 4,000 will be produced more than a month in advance.
PlugIn’s work order requirement matching
In response to this situation, PlanMate matched customer demand work orders in PlugIn and output split and merge reports to help customers split and merge in ERP.
Because ERP will run the purchase order in the early morning of Sunday, the schedule is scheduled to start at 7 pm on Saturday. At 7 pm on Saturday, all departments will suspend the inbound and outbound operations in the ERP, and the supply and production management will start scheduling operations.
First run:
- Download work orders, requirements, inventory, and issue lists.
- Demand is deducted from inventory and then matched with work orders. If the work order spans more than one week, it is recommended to split the work order and output a split report.
- Import the split report into ERP and perform splitting.
- After splitting, export the above report again. At this time, the work order has been split.
Second run:
- Combine small work orders with similar demand times and output a work order consolidation report.
- Output the consolidated report to ERP and perform work order consolidation.
- After ERP completes the work order merging, export the report again and PlunIn reads the report.
Third run:
- After the work orders are merged, export the report again.
- Perform work order requirement matching.
- Output the new start date of the work order.
- Return new start date to ERP.
- ERP reads the start date report and updates the start date.
Through the above multiple matchings and execution of splits and mergers, after the system went online, the overall inventory level in the factory was reduced by 20%.
Customer problem point 2:
The production in the factory is mainly divided into the SMT section and the DIP assembly section. Different production lines and processes are responsible for different floors and processes. However, because the model is unified and there are constraints in scheduling, each production line cannot be independently scheduled, so PlanMate uses one person. Scheduling, regional maintenance methods, and division of operation permissions.
The production management of each region can only modify the plan of the resources it is responsible for, and can view the tasks of other regions. By reading the daily production report to update the progress, fine-tune the plan, and then lock the tasks for the next 24 hours before running the schedule.
Customer background:
PlanMate not only provides solutions for large enterprises, but also for small and medium-sized enterprises. Hefei Xinglian Technology is an example of a solution for small and medium-sized enterprises. Customers produce various types of network cable products, which are mainly divided into the following processes:
BOM hierarchy:
A network cable is composed of 8 wires. After the single wires are extruded, they are twisted into pairs to form 4 strands. Then the 4 pairs of wires are twisted together again, and a metal bottom line and outer quilt are added. Therefore, BOM is divided into 4 levels. When twisting and twisting together, the length of the wire should be shortened, and the BOM consumption is a fraction.
Schedule data:
The network cable industry does not consider material inventory restrictions, but it must consider finished product and semi-finished product inventory.
This project does not require an ERP interface. All files are imported from Excel, including
customer order
Inventory: finished products and semi-finished products
After the finished product order is imported, the finished product inventory is deducted and converted into a production work order. When running the schedule, the system will automatically generate half-product production tasks.
The inventory quantity will be deducted from the half-finished task first. If production is needed, it will be queued online.
Field data – actual progress
The customer has not imported the MES system, and the production progress data needs to be entered manually.
PlanMate generates a production plan for each shift by shift and displays it in the production capacity entry module.
The actual completed quantity is entered at the workshop site after each work order is completed or when a shift is changed.