Article written by: PhD. George Ogrinja, Supply Chain Director, Associate Professor Faculty of Economic Cybernetics, Statistics and Informatics, ASE Bucharest
Second part of the article: WMS – do we treat the causes or the symptoms?
c) Correlation of picking and shipping processes for timely order delivery, etc.
The problem: “We are in the expedition area, where the cargo units are formed and checked before delivery. The floor area is full of pallets that have been waiting for hours to be loaded, while other customer orders packages are waiting to be packaged, marked and labeled because of the lack of page. Because of the excess of pallets and packages, the demarcation line between the routes disappeared, and there is an increased probability for goods that have already been checked, to migrate from one route to another.
Why this situation? One of the main causes is: “the warehouse doesn’t process orders deliveries based on priority”.
What can be done?”
An effective solution is to synchronize picking and shipping activities based on transport routes (route starting time, allocated customers, etc). In this case, the implementation of the “Advanced Wave Planning” WMS option allows grouping multiple commands in a “wave/ batch” and launching their picking according to the daily schedule of routing trucks. Sometimes, “Advanced Wave Planning” function is included in the dispatcher module of WMS that provides complete information on all operations of a warehouse , monitoring all stages of orders processing, the activity of commercial workers, and so on.
d) Efficient management of inbound processes (dock management, receiving and put away)
The problem: “We are in the reception area of the warehouse. In every dock reception area a vehicle is waiting for someone to start the reception. Inside or outside of the warehouse yard other vehicles are waiting their unloading. These operations repeat daily and the reception operations that are not finished during the day are transferred to the night shift.
The floor of the reception area is completely covered by goods and stack pallets are hard to identify. In order to solve the situation two other fork lift truck operators were asked but the approval of the requests from the CFO is not coming. In the absence of a response, the warehouse manager decides to extend the reception zone in an area where there are already stored pallets with hundreds of articles, some of which already have damaged packaging. The area is isolated by a plastic strip where there is a “hanging” handwritten placard that says “Goods in reception process”.
What is to be done?”
There are several operations that are valid regardless of the warehouse automation degree:
a) Delivery notification from the supplier (day schedule) in order for the reception documents to be prepared by operators (open Purchase Order or ASN or Inbound Delivery)
b) Proper labeling, packaging, documentation of goods by the supplier (register supplier nonconformities vs. delivery conditions stipulated in the contract or standard delivery agreement). For example, the quantitative reception time increases in the following situations:
• individual items are delivered in a large box, although they could send it in cases according to the purchase order because the amount was expressed in units of packaging;
• delivering the same product from many lot numbers, etc.
c) Ensure the availability of personnel, pallets for receiving articles and handling equipment.
d) Assign proper storage cells for received items.
If the above measures are not sufficient, the high volume of reception activities recommends implementing a WMS system that will enable:
• using barcode technology to monitor quantitative reception of goods (real vs script)
• alert (beep) in case of non-compliance
• automatic drafting of reception documents
After confirming the correct reception, the WMS performs automatic allocation of storage cells by issuing an “inventory transfer document” to move products in the storage or picking area, depending on the stock level of each product. In order to minimize travel times, in the absence of urgent action, the Putaway process can be delayed until the accumulation of a large batch of merchandise.
Expanding the warehouse reception area is considered a wrong action and may signal an inefficient system reception system or an insufficient reception space. Whatever the cause, the manager’s decision to allocate an additional storage space for unreceived goods is wrong because non-inventoried products stored outside the reception area (or other special areas such as the quarantine) encourage fraud or theft.
The problem: In the storage area of the warehouse there are pallets with goods on the access paths. The operator of the fork lift truck receives a picking order for a pallet stored on a higher level of the storage rack. In order to access it, he takes the pallet that it obstructing and moves it a few feet back on the floor. Also, in the first location of warehouse there are pallets with a thick layer of dust on them, which suggests their wrong positioning.
The dust suggests that the object hasn’t been touched for months. The fact that this dusty pallet occupies a position designed for products with high turnover speed, needs a fast slotting/re-slotting strategy analysis. The way in which the pallet stored on the access path was acted upon (moving it a few feet on the floor) confirms the absence of clear and strict rules of space allocation that finally allowed the manifestation of some form of indiscipline.
Therefore, an analysis of the stock movement reports and the reevaluation of the re-slotting strategy is needed. For a complete approach of the problem, the “rules engine” for “Task management” must be evaluated, since it is possible to see the operator picking packages and not pallets with the forklift truck.
e) Correct selection of the picking method
The problem: The picking operators make too many trips to collect the same items that are found frequently in customer orders. It is necessary, for example, to change the picking method from Pick and Pass to Wave Picking or from Single Order to Batch Order according to the situation of the open orders, handling equipment and delivery schedule. It is possible to use several methods of picking? Who decides the method selection rules and how can the performance of the changes be evaluated?
The selection of the picking method is based on many criteria, one of the most important being the profile of the customer orders (total orders, handled product characteristics, number of lines per order, the average quantity per command line, number of lines collected per SKU, SKU number picked, the picking mode).
For the assessment of the performance of a picking method or the warehouse productivity Task Management and Workforce Supervisor modules are very useful for determining the execution of the operation cycles. A modern warehouse may have a zone that serves the Web customers (items picking zone) or areas serving traditional retail customers, distributors, manufacturers, where the picking is done by boxes/cartons and (or) pallets. The operations flow differs from day to day and during the same day, from hour to hour. Picking methods differ from one area to another, and so does the allocation of resources. In these situations the WMS Task Management module is particularly useful in allocating tasks/resources (people, equipment) in order to increase the efficiency of the warehouse. To calculate the productivity, to generate compared analysis (methods, equipment) the WMS can be configured (by rules engine) to allow gathering the execution times of warehouse activities and to determine the shortest process execution cycles.
f) The accuracy of the physical inventory without stopping the warehouse activity, etc.
Inventory Accuracy is one of the main criteria for assessing the performance of a warehouse.
The problem: The Customer Service Department informs the Purchasing and Logistics Department that order fill rate is about 75%. The Purchasing Department analyzes the book inventory level and considers that future sales are covered by the stock. The Logistics Manager collects and analyzes information from the picking lists submitted by operators. An analysis of the stock in the warehouse clearly reflects differences between book and physical inventories.
The discrepancies causes are multiple, but they could be avoided both by monitoring more efficiently the internal operations and by realizing cyclical inventory processes.
What is to be done?
The solution: Implement a regular routine procedure in WMS based on a Cycle counting function which you use to count a limited amount of stock, according to date or bin.
Because cyclical inventory operations are secondary in relation to others activities of the operators (receiving, putaway, picking, packing, shipping) an automatic procedure in WMS for periodic inventory lists is the solution of the problem.
The inventory cycle counting plan is included in the set of rules of the “task management” module and issues partial inventory lists (product number, stock, locations, etc.) that are made according to the number of articles, the class of inventory turnover (A, B, C) and number of days needed to complete the inventory of each class. Periodic inventory lists can be generated and stored in the database being automatically launched by the Supervisor Workforce operator or retrieved by the operator when there are no other tasks in the warehouse system. The differences between the stock records and the physical stock are exported into the ERP system.
II Effective labor management
A few mentions of the Labor Management importance in WMS system:
1. The workforce represents approximately 45% of the operational costs of a warehouse (there is great pressure on reducing the operating costs of the warehouse).
2. Reductions in labor costs per unit handled (% Decrease in warehouse Labor cost per unit handled vs. last year) is the 2nd important performance indicator in the selection of a best in class warehouse.
That’s why are therefore preferred WMS with Labor Management functionality, WMS with Labor Tracking or WMS with Task Management (manager).
The problem: The Customer Service Department informs the warehouse manager about the worrying increase in the number of nonconforming supplies (missing goods or incorrect quantities, damaged packaging, errors in documents shipping, the timeliness of delivery, etc.). Who is guilty? Can the warehouse manager undertake an analysis of the activity of each employee in the warehouse?
One of the most common problems of WMS that operate on written documents is lost or wandering picking lists.
An analysis of the errors in the paper-based picking system is never a complete one. Some causes may be mentioned:
• lack of picking lists, especially when using the Pick and Pass method (a picker assigned to a storage area) when the original order list is divided into picking sections.
• monitoring processes, (putaway, picking, reception, etc.) rather than each person’s activity.
• data collection and processing are very difficult.
In paper-based picking, most times in case of repeated mistakes, it is used the collective penalty, a practice that discourages all workers to be efficiently.
This is because many WMS systems do not allow warehouse manager assessment of the individual worker in the warehouse, such as:
• Number of orders
• Number of order lines
• Average number of lines received, picked, etc.
• Pick quantity per minute / hour / day / month
• The date and time of each order delivery or shipping
• Reception, Putaway, Picking and Delivery discrepancies
• Hourly intervals between deliveries
• Monitoring performance drivers by integrating WMS TMS systems, etc.
The solution is: WMS with Labor and Productivity Tracking function for evaluating individual productivity of employees and establishing proper procedures for penalty or incentive and reward. Implementing performance monitoring option of warehouse operators involves the introduction of bar codes or RFID, allocation of individual tasks and confirmation by the operator at each stage of the internal operations cycle.
All lists on the internal operations of the warehouse are stored electronically for viewing, printing or analysis.
The problem: The alternating periods of peak activity and relaxation during the working day.
Warehouse operators tasks are very complex and the job description is provided for the main and secondary activities. For example, the main task of a picker is to pick the assigned orders, but it may have allocated secondary activities like re-slotting, partial inventory, picking area replenishment or other routine tasks. Secondary planning activities are done outside the peak period of activity, but the maintenance of a balance between efficient tasks and resources (people, equipment) is very difficult. Most often secondary tasks are neglected, the operator invoking, without the possibility of being thoroughly contradicted, the reason of time.
What can be done?
Warehouse manager may design rules engines for allocating tasks per operators related to relocation, inventory cycle counting, picking areas replenishment and other related processes depending on the degree of the operators task loading.
Improved productivity is one of the primary benefits of a WMS, and task management is the core functionality that drives labor efficiencies.
Practitioners in the world today say: “If a WMS does not have task management, then it is not, by definition, a warehouse management system”.