Most sawmills and pallet plants have at least one bottleneck or critical flaw. And knowing where it is and how to fix it can be the difference between a good and a bad year. It all starts with the flow of material through your facility. Plant layout and design are critical to success, and yet it is amazing how little time many companies spend thinking about this issue.
In this article, experts offer tips on ways to improve your existing facility or factors to consider if planning a complete redesign.
The Benefits of Working with an Engineering Firm for Sawmill Projects
Bernie Pahlke, president of BEP Engineering Services, has been involved with sawmill design for 45 years. “We work with a lot of vendors,” he explained. Based on BEP’s experience, their staff knows what type of equipment a vendor might do very well, and when to introduce and combine machinery from other vendors in order to achieve the best result. Equipment vendors, he noted, are very good at developing and manufacturing their equipment and giving advice on how to get the most from it. They might be less suited, however, to providing insight regarding mill installation and integration with equipment from other suppliers.
Pahlke uses the example of a mill manager who is considering a new edger. If he goes directly to the vendor to determine an installed price, the dollar figure they receive is highly contingent. The contingency relates to uncertainties involved in a successful installation. In order to cover for contingencies, the vendor may set a price that is too high. At the other end of the spectrum, an under-estimate might result in cost overruns.
Getting back to the new edger, Pahlke noted that the installed price might be double or more of the equipment purchase. “There are going to be uncertainties,” he explained. “It might not even fit in the plant.” Other installation complications might include existing refuse systems, support steel, foundations, building services or columns, not to mention interaction with other machinery. The project may require conversations with other vendors.
By working with a mill design firm, however, mill operators benefit from their considerable experience in all elements of a mill project as well as being very familiar with a complete range of vendors. Mill designers offer an unbiased approach to equipment selection based on creating the best overall solution.
The design process usually begins with a desire from the mill to improve flow or perhaps to go after a new market opportunity. One example would be installing a planer and kiln to produce higher value dimensional lumber. “The mill maintenance manager looks at who else is doing it, what equipment they are using, and he comes up with what equipment he would like to use,” Pahlke explained.
That’s where Pahlke recommends enlisting the help of a mill design service to create the scope of the project and prove out the return-on-investment (ROI). “We look at how the new equipment would fit in his plant. Then the mill goes back to the vendor with the question, How much? Now, the contingencies can be removed, and the mill can receive accurate pricing, because you have enough information.”
The initial scope drawings created by the mill design firm allow everyone to be on the same page with input from all decision makers. Scope is a term that Pahlke uses frequently. It refers to the creation of a visual solution that all involved in a project can understand and follow. A good scope, he stated, is one which creatively accomplishes the most for the least. An experienced mill designer, who focuses only on design, can provide a wealth of experience to a project and provide outcomes that outperform expectations, delivering creative solutions at least cost. Such a difference can help customers remain profitable even during industry downturns.
Pitfalls and Negative
Outcomes of Poor Design
1. Vendors and installation contractors either apply contingencies to cover uncertainties or later require major extras to complete your project.
2. Poor scope can cost huge amounts of time and money to fix. These repairs balloon your budget and are usually unaffordable.
3. Inadequate scope can negatively affect your payback and production, which impacts the opportunity to get additional funding for future projects.
4. An unclear vision of what is expected and what it costs can result in litigation to cover the extra costs needed for completion.
5. In the worst cases, project managers can lose their jobs, contractors can go out of business and your mill or plant could shut down.
Source: BEP Engineering
Preferred Project Plan Sequence
1) ROI anticipated by the owner from changing something
2) Potential equipment identified by the owner
3) A budget provided for the project scope and the selection of a mill designer with the right experience
4) Site trip by the mill designer to establish scope alternate sketches together with all who have input at the mill and then select the best option
5) Measure existing equipment, buildings, components and services
6) Deliver new layout using optimal equipment to gain optimum solution tie-ins to existing facility. This initial scope is used to accurately establish the ROI
7) Once the ROI is acceptable, detail drawings are produced for fabrication and installation as well as to vendors
8) Drawings are put out to bid for competitive pricing to vendors, fabricators and installers, etc.
9) Contracts awarded
10) Inspection and visitations to monitor progress
11) Supervision of the installation
Source: BEP Engineering
Considerations for Optimal Pallet Plant Design
When it comes to improvements to pallet plant design, an owner’s desire to improve safety, output quality, and efficiency are key motivations to move forward, according to Kurt Larsen, integrator & COO at Viking Engineering. In order to achieve those aspirations, he recommends that operators shorten their material flows, choose the most appropriate automation and design for the flexibility needed to suit their operation. “They have to balance those three things in order to get their maximum yield,” he explained.
Larsen suggests that owners begin with a desired output or end goal in mind. “When I go out and talk to people,” he said, “I often hear that they are trying to grow their business. They realize they have to do something with their saw line, or automation related to producing the pallet.”
Larsen has found that people often make an investment in their saw line, and their next step is to boost their nailing capacity for pallets. “Perhaps they used to run a Champion, but now they are getting enough wood to run a 505 or a 606,” he said. “You have to get the wood before you can make the pallets. Usually one comes before the other. If you get serious about your wood, then you can get serious about pallet production.” Companies must find a solution to best manage their wood, labor and nail costs.
As for shortening material flows, there are several things to consider. “When you are designing a new shop,” Larsen observed, “you can make sure it meets all of your requirements, but when you are dealing with an existing structure, it can be a little tougher.” He recommends establishing a clear line of sight in moving material to the production line, shortening the distance as much as possible and minimizing handling.
Inefficient material flow can be found in older buildings with various workstations and rooms that have been introduced over time. Larsen cites the example of a pallet shop that had pallet lines in separate rooms. “Forklifts would have to frequently go around blind corners and do U-turns to get from one room to the next to get materials to the machine,” he explained. The building had a low ceiling and a lot of obstructions. “You would always have to stop and blow your horn when you went around a corner to make sure you didn’t hit another forklift.”
In the new pallet manufacturing facility, material handlers travel a straight run from the sawmill directly to the assembly machine. At the other end of the machine, stacked pallets once again go in a straight line directly into storage. “You want to have the end of the machine as close as possible to the exit so you can remove the finished pallets from the stacker as quickly as possible,” he explained.
On the infeed side, look to minimize the distance from the sawmill to the pallet assembly operation, or if cut stock is being used, look to reduce as much as possible the travel time between the unloading area, storage and production. Also plan and organize material storage to minimize the amount of handling required. Sequencing stock in the order needed can be made easier with new generation equipment.
“Some of our machines help with that because they provide an estimate of the production rate,” explained Scott Ellefson, sales manager for Viking. “If you are running our new Turbo 606, you know what materials you are going to require, based on information displayed on the screen.”
With regard to the need for flexible design, Larsen observed that it really depends on your business mix. “If you are dealing with customers that only take GMAs, flexibility becomes almost a non-issue. You are going to make the same pallets on the same machine every day, and just get your materials in and out,” he said. “If you do a lot of changeovers, you want to make sure your materials are prepped and ready to go. You should have materials staged, or at least know where they are and get them to the machine in the shortest amount of time.” If what should be a five minute changeover turns into a 15 minute changeover, he cautioned, you’ve lost a lot of pallets.
Safety considerations are a crucial element of plant design, and creating a clear line of travel and sight through eliminating obstacles or cleaning up clutter can not only reduce the risk of collision, but also significantly boost material flow. Other designs for safety include establishing traffic flow rules and clearly marking lanes to segregate pedestrians and forklifts.
Design for fire safety is another critical area of consideration, involving such measures as dust collection systems or design for easy access to areas where dust might accumulate and need to be removed. Other fire precaution considerations include the location of fire suppression equipment and access to it, material setbacks from buildings, clear roadways for emergency vehicle access, and so on.
Ultimately, Larsen suggested that the goal of plant design is to optimize safety, quality and efficiency through attention to material flows, automation and flexibility. It is a balancing act, which if done correctly, can help operators achieve their desired yield while maximizing output per man per hour.
For more information, visit www.vikingeng.com and www.bepengineering.com. BEP Engineering will be exhibiting at the 2017 Forest Products Machinery & Equipment Exposition, to be held June 14-16 in Atlanta, Georgia.
