Better by design
April 1st 2007

Horizontal carousels offer reliable and cost effective storage, achieving high pick rates and effective space utilisation. One company at the forefront of development in this area is Diamond Phoenix

The size and use of carousel systems varies significantly, from small stockroom applications and hand picking point-of-use items to highly sophisticated, fully integrated systems moving thousands of boxes per day. As a result of value engineering, horizontal carousel systems have evolved to achieve a very flexible and versatile product.

Original carousels were built on a per job basis. A range of sizes was eventually developed to satisfy applications using totes or dedicated boxes for individual parts storage. Early models were based on 18" and 24" requirements and were partially driven by the advent of plastic and/or reusable returnable totes.

The challenge was to design a system that met customer needs in a reasonable amount of time. Although each carousel had common components, varying capacity and available space made for widely different carousel sizes (length, height and weight capacity). It was nearly impossible to stock components across all of the designs and still expect a cost effective and timely solution.

Common track Diamond Phoenix engineers set out to resolve this. In previous designs, the space between bins was fixed so that they were evenly spaced and the carousel track (the oval that supports and guides the bins as they move around and around) had to be a unique size to suit the evenly divided carousel chain. By adopting a small variation in the design – fixing the carousel frame and simply varying the space between bins – a common track was produced to suit all bin sizes.

The carousel chain path had to be divided into smaller lengths and then combined in groups of two and three pitches to accommodate the most common bin widths. Common track meant that frames could be stocked for any number of forecasted carousel projects and could be used for any job. Only the 'odd' carousel track section that made the track length unique to the application had to be made specifically for that job – all other components came out of stock. Today, stock components are manufactured for both the top and bottom track sections and the variation in height based on the bin is simply adjusted with common stanchions cut to length as required.

The next piece of the flexibility formula was to make sure the individual line component used to make up the chain and moving gear remained common across all models and weight requirements. Carousel capacities vary greatly and early designs used appropriately sized components to keep costs down. However, ever expanding inventories were required to keep an abundant supply of components in stock.

The Diamond Phoenix solution was to use common bearings and load bars across all weight capacities and combine them in different groupings to support varying loads. In this scheme, a smaller number of bearings carries a light load and larger group of the same bearing carries heavier loads. Combine this with a selection of material for load bars and you have the same 'stock' components carrying widely different loads.

Diamond Phoenix also designs and builds its own wire product (bins and shelves) in-house. With roughly a million combinations of capacity, height, width, depth and shelf spacing, stocking 'standard product' was not feasible. However, the design of flexible jigs and fixtures to suit various sizes allowed modularity on the manufacturing side and enhanced versatility in building product when combined with the ability to cut, form and spot weld wire product in-house.

Engineering tools allowed the design of wire product to closely follow the order entry function. There is never a long lead time in the manufacturing chain – an order entered is an order started in production.

Finally, a common platform of control components provides the ability to build controls from foot switches to sophisticated control schemes using offthe- shelf components from electrical equipment suppliers. This has two advantages: easily obtainable components and the ability to allow the customer to dictate the 'make' of electronic/electrical components used in a given project.

Customers stock fewer spare part components and there is a high degree of reliability in the final product, avoiding the pitfall of proprietary electronic/electrical design in a world of fast moving and changing component availability.

Quick delivery Diamond Phoenix's combination of common base frames and components, inhouse wire manufacturing and the use of standard electrical components is a recipe for quick and reliable deliveries – no one in the industry is faster and no one is better.

The customer wins with the lowest possible price, quick deliveries, in stock spare/replacement parts, and the ease of expanding the system in the future.

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