The purpose of placing goods in a warehouse is to store them safely until they can be picked and delivered to a customer. Once goods are stored in a warehouse they will be picked at some point in the future. At the time of picking goods, it is efficient to have a pick path as short as possible. This will save costs, time and resources for the warehouse operations. Optimal product placement within the warehouse can lead to significant improvement in warehouse efficiency.
In a warehouse, the pick path is the distance between the dispatch area and pick bin. This distance could be horizontal and/or vertical. The horizontal pick path is the distance, along the ground, a picker needs to travel from pick bin to dispatch area to complete a pick. Vertical distance is a consideration in warehouses that have racking in place, meaning pickers may need to pick products from level 2 or above, where special equipment such as a forklift may be required.
To reduce pick pack horizontally and vertically, warehouse management systems widely use two functions one is slotting, and another is advance replenishment. If these warehouse management functions are implemented and used correctly, they will result in reducing the pick path significantly. In this post, we will discuss these two concepts and see how warehouses can take advantage of a warehouse management system to reduce their pick path.
Slotting
To reduce the horizontal pick path, goods need to be as close to the dispatch area as possible. So, the question is, which products will be close to dispatch are and which products will be placed towards the rear of the warehouse. One way to determine this is by using 20-80 rule. It says that 20 per cent of the products make up 80 per cent of the operations. Hence warehouse can sort these 20 per cent of their inventory into areas near the dispatch doors. To achieve this, warehouse management systems use a functionality called slotting. Using slotting, the warehouse team could setup logic in the WMS where the system could suggest to the warehouse team where each product should be put. The key logic that a WMS uses to suggest bin location to the warehouse team includes:
The Velocity of Each Product
Parameters and logic can be set up in the WMS to calculate velocity. It could be monthly, fortnightly or yearly. The system could also be set up to calculate the last period velocity or moving average velocity.
The Golden Zone
In WMS, the Golden Zone can be defined as the area or bin locations where fast-moving products should be placed. This location is generally closer to the dispatch area.
Using this setup WMS systems can assist the warehouse team to generate inventory movement. Firstly, this can be achieved by placing fast-moving products in the golden zone and secondly, moving the slow-moving products towards the rear of the warehouse.
Warehouses that use the slotting function, run this process periodically and inventory could be moved within the warehouse accordingly, as per the system’s suggestions. The WMS will ensure that there is a place for everything and everything in its place.
A place for everything and everything in its place
Benjamin Franklin
To gain better results from slotting, zones could be added to the warehouse setup. In other words, bins containing fast-moving products could be set up as a separate zone, and dedicated pickers could be assigned to complete picking in this zone only. The combination of slotting used with zone picking leads to a reduction of overall order picking time.
Replenishment
Moving a product to the golden zone will reduce the pick path. However, if the product is sitting on the higher levels on racking, it will still take picker time to get the product from overhead bins to floor and then pick it. In warehouse moving vertically is more time consuming and costly than moving horizontally. So, the rule of thumb is to place all products to be picked on the ground level bins instead of higher levels on the racks. If this is not possible, then place fast-moving products on the ground level and move slow-moving products to higher rack levels only if there is no place on the ground level bins.
The concept is, that a picker will not need to get down a product from a higher-level bin whilst in the middle of any order pick. The reason is simple, to get a product from higher-level bins special equipment, expertise and a licence is required. For example, complete an order involving a pallet from higher racking bin locations, a forklift may be required and a forklift driver who has the required licence. This not only stops or breaks the flow of the picking but also requires someone else to work on the order before the pick can be completed.
WMS use replenishment to reduce if not eliminate these bottlenecks. The concept of advance replenishment allows the warehouse team to maintain the required inventory in pick bins and therefore reduce the need for replenishment during picking.
Advance replenishment could be set up using minimum and maximum holding capacity of the pick bins or velocity-based replenishment request. Some warehouse use order-based replenishment process where the required inventory to fulfil a wave of orders will be replenished to pick bins before pickers start picking orders. Using order-based replenishment ensures that inventory in all pick bins is enough to fulfil all orders to be picked in the next wave. Irrespective of the processes and the techniques used by a warehouse to reduce the pick path, modern Warehouse Management Systems (WMS) have advance functions and comprehensive setup which will fulfil complex warehouse requirements. This is to ensure Business is using modern technology and concepts to get ahead in their business and having a competitive advantage.
Note: Views in this article are generic in nature, please talk to your consultant or warehouse expert before deciding on Implementing new WMS solution or changing your existing warehouse policies.
