Wednesday 9 January 2019

ITS ALL ABOUT PICKING : SAP EWM view


In general, a warehouse and its contents are of no value, rather a major cost driver.
Its main purpose is to provide time and place utility to satisfy customer needs. Without the need for time and place utility a warehouse is of no purpose.
To provide time and place utility one of the fundamental aspect relates to efficacy, efficacy of picking, packing, labeling and shipment on time and in full of the correct ordered goods.
A high-volume warehouse will have many Transportation Units (TU) arriving throughout the day to load and deliver. These TU are of different size and will load packed boxes and pallets for delivery to different routes: deport for export, or from cross dock and de-consolidation or direct delivery.

This implies that the warehouse must synchronize picking so that goods are available with agreed loading time frame, correctly packed and labelled for loading.

From SAP perspective the key processes are as follows:
·         Sales orders are generated for customer to provide specific products at a desired date. Normally different order types are created to deal with exports, domestic ect..for ship to parties that are on a specific route. The sales order may have item quantities that may be defined as items, box or pallets. The sales order may contain specific batches or may contain a batch search strategy to determine ideal batches. The confirmed dates with respect to availability validate available qty and delivery date that is theoretical (rarely takes into consideration supply chain and warehouse issue)
·         Other types of outbound are triggered by stock transfer order for inter plant transfer. Quantities may be optimized based on type of planning system used of simply derived by MRP
·         Deliveries for the respective sales orders are then created based on available warehouse stock. Delivery creation considers the warehouse as block box: indifferent of availability single items, boxes and cartons, indifferent of the transportation unit capacity (possible up to a point if APO Transportation load Builder) , indifferent of load optimization or load sequencing
Deliveries are the key enables for commencing EWM warehouse picking operations. Different type of deliveries will determine if for cross plant transfer, domestic or export. In high volume warehouse picking by deliveries not an option. This will result in in operational delay, confusion and inefficiencies.

The ideal operational process flow is to ensure operational efficiency. This is done as follows:

ASSIGNMENT OF DELIVERIES TO SHIPMENTS
1.      Collect all the deliveries and assign to a Transportation unit. Each transportation unit represent a specific vehicle.

Normally all organization negotiate with shipping agent’s shipment service which include type of vehicle and route schedule. Each transportation unit will be responsible for delivering according to specific route and loading volume is approximated. This can be done via the following functionality:

o   In ERP to limited extent. No truck load optimization is possible load sequencing. Shipment creation allows selection and deliveries to be included with following selection criteria:

Delivery selection

Transportation criteria
Once created system generates shipment document with assigned deliveries

Shipment document is then replicated to EWM by means of IDOC which in turn creates a Transportation unit with assigned deliveries.
The above creation limitation does not have any form of load optimization and delivery grouping simplistically grouped.

o   Creation of Transportation unit in the EWM system. This is possible from shipping cockpit functionality that displays all the deliveries, planner then selects deliveries to be grouped in newly created TU.

Shipment cockpit via transaction NBWC (not part of SAP GUI transactions)

Deliveries displayed in cockpit

Transportation Unit creation criteria

Created Transportation unit with assigned deliveries. The transportation unit are not optimized in terms delivery route and load optimization.

o   Manually create Transportation Unit via transaction /SCWM/TU and assign deliveries.

TU creation criteria

Assign deliveries

Created TU with assigned deliveries

o   Alternative way via third party solution. This implies sending delivery documents via IDOC or other to external system that manages routing and load optimization. This third-party software will then have grouped deliveries in unique shipping units that are optimized by route and are loading volume optimized. These shipping units with assigned deliveries, product and qty are then interfaced (custom) ideally into EWM system by creating a Transportation Unit with assigned deliveries in the EWM system. Possible vendor : https://ortec.com/

Note: in all cases it possible to split deliveries across multiple TU due to load optimization and constraints.
Up to this process step SAP functionality has all the capabilities to create shipment but not perfectly optimized unless third party tool is used.
Depending on the business complexity with respect to delivery route management and load optimization it may be the standard offering within SAP and EWM may be adequate with a simple enhancement if needed.
Once we have the TU with assigned deliveries EWM can then really earn its value by triggering the follow-on step. This where EWM has all the functionality to carry-out effective and efficient picking and shipment.

At this point we have in the system many TU but it does not mean that the warehouse items are ideally stocked. TU are now structured as follows:

TU per vehicle and has expected planned date and time (approximate)

Deliveries
Deliveries may allow for peace’s, carton, packs a and pallet. Also, it may be that pallets are stored in high bay warehouse where some form of FEFO logic is needed.
EWM offers replenishment that can either based on min levels or order-based replenishment. The selection of how to manage the replenishment criteria depends has pros and cons.

Important to note that both methods trigger replenishment activities that may not be completed on time to satisfy TU:
·         Planned replenishment check all stock levels and is indifferent to outbound requirements. Limit this to single peace picking areas such a vertical carousel or pick to lite systems
·         Order based considers deliveries and is indifferent to planned shipments
·         Ideally order based should be based on planned TU, but TU is not part of selection criteria

Moving on:
PRE PLANNING THE SHIPMENTS
Once the TU are in place with expected date and time carry-out the following steps:

        Yard management
      This is an optional process, dependency is based on complexity, volume of vehicles and control that is required. Yard functionality to be used for check in of vehicle, weighing, sealing and check-out

                                                          Functions related to yard mgt

Shipping cockpit assign door

In the shipping cockpit

Assign door. This will be the door TU will arrive to be loaded. Important to setup goods issue bins to relevant door. This is fundamental for warehouse task such that pick destination bin displays goods issue bin associated to bin.

Staging bay door relationship.
Shipping cockpit the clearly displays that TU assigned to door

TU visibility and status of door assignment.

 Assignment of the door to TU automatically assigns door to delivery.
At this point in time may be necessary to modify TU date and time. Note: if this is done once picking is started then WO date are not adjusted therefore enhancement is required. This is fundamental to re-sequencing WO picking which is based on system guided picking.

       Assign wave. Once door is assigned assign wave to the TU. Wave creation will then trigger picking and this is where efficacy is gained in that picking managed because automated. Even is not all warehouse are created, planned job (say every 10 minutes) will re-release the wave to create any outstanding picks.


Wave can either be manually assigned or automatically. Once wave is created depending on type of release warehouse tasks are created where picking strategies are successful.

Possible option is to create wave that are not released: this will then require further step within the cockpit to release the wave. Decision of not releasing wave on creation depends on timing and pick volumes. Create wave not released enables replenishment to already consider these TU that have wave assigned but not yet started. Release the wave within narrow window to trigger picking.


It is now fundamental to set-up replenishment to run based on orders but with wave template defined. This implies that deliveries are selected that are assigned to TU and have specific wave template assigned. Consider enhancement to sort deliveries for replenishment based on TU sequence. This ensure that replenishment tasks sequenced accordingly.
Further enhancement is required to consider batch search strategies associated to outbound delivery must be considered when carry-out replenishment. No use having replenishment for batches that do not fit batch search strategy.
Further enhancement is needed if there is a need for multi-level replenishment: pallet > carton>peace’s.
Very important: activate wave mgt for replenishment, this is fundamental to automate steps and avoids excessive human effort. Operator effort purely manage exception where Ware task creation fails.
       Carry-out picking. Wave release will trigger warehouse tasks creation. Efficacy all depends on smart pick strategies are defined. Wave via background job will automatically be released in background to create any missing warehouse tasks due to replenishment tasks running in background. Warehouse order creation rules, queue assignment is fundamental to ensure warehouse order efficacy. This is to ensure that picking tasks are assigned to correct type of resource.


Warehouse order, associated to wave, queue with assigned warehouse tasks. Sequencing of WO must correspond to TU sequencing. This to ensure that when relevant truck arrives products are ready to be loaded.

99% picking activity either carried out via RF, automated crane system, pick to lite, voice pick. the remaining 1% managed manually only for exception. High number manual process confirms badly designed signed.
5.       Labeling
Once picking commences labels are needed. Normally if full pallet picking is carried, re-use of existing HU may be possible. It may that customer specific labels may be needed. Mass printing of labels will be disastrous for any warehouse operation. Labels need to be printed on demand associated to resource that is doing the picking.  This why small label printers attached to belts of RF operator or fork lift trucks will ensure correct label for correct item that is picked.

         Documentation
Many EWM implementations carry-out the usual error by printing delivery notes and packing list from ERP system instead of EWM. This causes all sort of problem in that there is dependency for goods issue to be carried out in ERP to print documentation. Ideal solution is to print documentation from EWM system rather than ERP system.

  Loading
EWM offers the ability to create loading WT, important to understand need for this kind of detail. It may result in unnecessary system effort. Simply update by updating loading in TU to indicate loading complete. Loading complete status can be used to automatically trigger printing of delivery note and packing lists.

  Close shipment
This tasks is needed to free-up door and indicate completion of TU activity.

There may be requirement to update seal number, this may be done at TU level and vehicle level as well as update from weighing station.
Departure from checkpoint then closes the TU and is further critical event to trigger update to ERP system of the TU so that shipment is created and if necessary shipping cost generated.  

Conclusion
 In any warehouse the real value is picking. Warehousing and shipment process to satisfy time and place utility which generates income (billing). Therefore, efficacy within warehousing solution is critical:
·         Efficacy in system operation
·         Efficacy in actual warehouse operation by resource.