Bringing New Life to Old EquipmentBy Leslie Langnau, Senior Technical Editor. In a 24/7 world, retrofitting offers material handling managers a way to deal with the challenges of aging equipment and new productivity demands. Age hits all material handling equipment. Wear and tear cut into productivity. Newer technologies outperform older features. And vendors stop stocking replacement parts, pushing equipment into retirement. But age is not the only reason to upgrade equipment. As businesses embrace business model after business model, retrofitting can be a great way to upgrade equipment functions at low cost. Often, for a fraction ol the cost of new, you can add flexibility and improve the performance of your systems, lengthen operating life, as well as reduce maintenance needs. Despite the benefits of retrofitting, though, it's not always a simple process. "Contractors are performing 'open-heart surgery' on someone's functioning, productive, mission-critical system," said Mike Kotecki, senior vice president, material handling integration at HK Systems, "while they're trying to get their job done. There's no tolerance for failure." To keep the disruption to a minimum and gain the most benefits, there are several steps managers and engineers can take. Out with the old? Whether you've decided to retrofit or even buy new, it's important to consider your objectives. For example, how long is the system expected to last? Is the retrofit to help control specific costs. like maintenance? "You also need to determine whether you will be handling the same types of items in five years," said Bill Craig, systems engineering manager for material handling solutions, Lockheed Martin. "Also, look at how well the current system meets the needs it was meant to satisfy. What's changed in the functions now required? For example, if you expect the need for throughput to increase by 20 percent, you can probably accommodate this with a retrofit. If throughput needs are higher, then you may want to buy new or add a parallel system." "Software should almost always be bought new," says Stafford Sterner, vice president of marketing at SJF Material Handling Equipment. "There's always upgrade potential with software." agreed Dan Labell, president of Westfalia. "The WMS algorithms can be improved, for example, grouping certain retrieval missions for better throughput. Plus, there's a lot of smarts that you can add to software that older systems may not have. Some of this newer technology runs in the background and really isn't noticeable. But, what you will see is greater flexibility in programming, such as using wireless communications to program PLCs. That's functionality that didn't exist before." "In today's world," added Sterner, "everything has a maximum life cycle of five years, including your business. The focus on how you run and do your business is in continual change. In five years, your present system isn't going to be what you want; your business model will change; the product and how you handle it will change; the way you bar code it, track it and inventory it, are all going to change. Don't get locked into trying to find a long-term, cure-all solution, because material handling is becoming an evolving process. "And if you see things changing significantly," continued Sterner, "retrofit may not be the solution." Another key factor is order profiles. "Profiles dictate the type of warehouse you should have and, thus, what can be retrofitted," said Paul O'Connell, president and CEO of Operations Concept. "Analyze your order profiles. "It's crucial to keep up with SKU profile maintenance," O'Connell continued. "For a warehouse management system to work well, it has to know cube information: weight, dimension, height, and so on. This is especially important when 60 percent to 70 percent of goods come in from overseas and U.S. companies let foreign vendors put product into just about any box they can find. Thus, the vendor may have changed the pack quantity. The biggest mistake made today is to accept these boxes without inspection. Maintenance is the most important function with WMS software and people don't do it. In addition to SKU maintenance, you need to do location, equipment profile and people profile maintenance too.", Once you've determined system objectives, it can be quite a project to choose among all the available component options. It's tempting to use new components just because they are new. "But those components may not be best for the application," said Kotecki. Several companies can help you analyze whether you really need the latest components through a "modernization audit." They will cornpare the existing system with your objectives and either develop a design for retrofit and/or new, depending on available funds. The factors these audits can consider include internal rate of return or net present value, power consumption, laBOR issues, maintenance, insurance costs, OSHA issues, even tax consequences of accelerated depreciation. They can even give you an expected return on investment. Some audits involve a simulation of the upgraded system, letting everyone see exactly what to expect from a retrofit. Others may be based on a program like Excel, which will provide speeds, through-puts, costs and other hard data. Bit by bit Whether you're refurbishing AS/RS systems, carousels or conveyors, there are common components that can give you the most bang for your buck. "For example, upgrades in motors, positioning systems and controls can boost throughput of automated storage and retrieval systems by 20 percent to 25 percent," said Craig. "Carousel upgrades usually consist of replacing some controls and mechanical elements, but the throughput won't be as high as with other material handling equipment. That's because people manage the picks in these systems. Control upgrades, how- ever, will often make the system easier to maintain and will improve reliability." "The software enhancements that have happened just in the past two years," said O'Connell, "have dramatically improved the efficiency of both mini-load and standard AS/RS systems. With these enhancements you'll get flexible picking, the ability to wave orders in many orientations, selective picking to order, bulk ordering, regional and state picking, and so on. Newer warehouse management programs work along with the equipment to give you the optimal or desired pick pattern." Increasingly, continuously moving equipment is being replaced by systems that run only when needed. For example, upgrading belt or shaft driven conveyors with roller conveyor systems that use photoelectric sensors to turn on roller sections only as needed. Not only does this change reduce noise levels, it's also a good way to save on power, given the recent energy availability problems. (For more on noise reduction and conveyor maintenance, read the article, Keep 'Em Running, page 45 in the February issue of MHM.) Large automated storage and retrieval systems can be very expensive to retrofit. But there are some economical upgrades you can make. "For example, you can change the algorithms, location dimensions, and zoning or location matrix criteria," added O'Connell. Interfacing When retrofitting, attention must be paid to interfacing new or refurbished components with the old. Most problems in linking industrial components have been solved. The problems that occur now involve linking industrial systems with corporate business systems, such as the host financial systems. No one expected the need to tap into financial systems and take data from them. "However," said Kotecki, "the good thing about this link is that you rarely have to communicate in real time." Special programs, usually known as software drivers, can be written by staff programmers or by system integrators, to facilitate the connection. In other interface cases, solutions involve the use of a cell controller. its function is to manage and isolate existing interfaces at the WMS or even AS/RS control level, reducing the disruption to these systems. "Be aware, though," said Sterner, "that vendors tend to recommend their own line partly to avoid potential integration issues." The latest development in retrofitting is to turn to "renewed" equipment. These pieces fit applications where you need devices for a new function but you don't want to buy brand new. Not quite new, yet a step beyond reconditioned, this equipment has undergone disassembly, evaluation and comparison to original specifications, and finally re-engineering to fit the needs of new applications. In some cases, these devices can cost about 50 percent less than a new device. Changes to material handling processes are increasing as new business models arrive. Upgrading equipment, in one format or another, is a good way to meet the demands brought about by these changes. MHM |



