Load It, Cut It, Stage It—Automatically?

Is it time to invest in band saw material handling equipment? To answer that question you need to ask more, like "Where is my bottleneck?"

A drawbridge option can open to remove trim or remnants and close to allow finished parts to move on. Photo courtesy of Behringer.

A drawbridge option can open to remove trim or remnants and close to allow finished parts to move on. Photo courtesy of Behringer.

The band saw is zipping through material. An operator is grabbing and stacking parts. Two or three employees are using a forklift or crane to position material for the next batch. Is it efficient? Productive? Is it time to invest in automated material handling for the band saw operation?

To answer those questions you need to ask more. Where is your bottleneck? Are conveyors already in place? How many employees get involved in the overall process? What type of material is typically cut, and how long does each cut take? What will your plant layout accommodate? Do you expect, or want, to up your band saw production in the future?

When a shop is ready to add automation, it has a number of options to choose from.

Joe Suydam, inside sales and marketing manager for Behringer Saws, said, “The decision of what type of material handling to invest in depends partly on the amount of material going through and how cut parts are handled on the output side. But a bigger question is the number of employees needed to generate the throughput and how their compensation fits into the equation.

“Fully automated systems, for example, have high upfront costs, but reduce the number of employees needed and the skill level they need to have. For the operators who are required, reduced physical handling, lower fatigue levels; and the barriers that are part of these systems create a safer work environment.”

Material handling can be an investment that is two or three times that of the saw, but, as Rick Arcaro, vice president of sales and marketing for HYDMECH, said, “It fuels bottom-line profitability, creates efficiency, and opens up other marketing avenues for a shop. You can have one of the fastest band saws in the world, but if you can’t feed it, you can’t produce parts.”

Basic Handling

A workcell environment can be created where material comes in the front door, moves through the sawing process, and finished parts flow out the back door. Photo courtesy of HYDMECH.

A workcell environment can be created where material comes in the front door, moves through the sawing process, and finished parts flow out the back door. Photo courtesy of HYDMECH.

The simplest of material handling options are roller conveyors. On the infeed side they support the material, eliminate a portion of the weight being put on the feed gripper, and move the stock forward. On the outfeed side they move cut pieces to a staging area. With added automation, the parts can be sorted by length into bins or pallets, and drops can be directed to separate locations.

“A band saw feed gripper has limitations regarding the amount of weight it can pull on its own without affecting the runout,” said Suydam. “Eventually you are going to need a powered or nonpowered roller conveyor, and that choice will depend on the size of material you process and how fast you want to move it.

“Between 40 and 50 per cent of our band saws go out with some type of infeed roller conveyor. The percentage isn’t as high for the output side--that choice depends on what is being run. About half of the roller conveyors are powered.”

For planning material handling, Arcaro cautioned to keep in mind that the same amount of material that goes in, comes out. “If you feed a 60-ft. piece of material into the saw, it will all come out the other side—just cut up. So if you add handling to the infeed side, you should add to outfeed.

“You can be flexible on the outfeed. If you know the cut lengths will be 20 ft. or shorter, you don’t need 60 ft. of outfeed material handling. Your typical cut length can determine the outfeed side requirements.”

Advanced Systems

Along with roller conveyors, a band saw can be surrounded by cross-transfer systems, length measuring units, cut to weight systems, sorting and ejection units, options that can combine for a turnkey sawing process. Beginning with loading the raw material.

Suydam said there are three basic magazine loading options:

• Incline–for round material because the magazine portion is on an incline. The bars roll down to a stop, where they are picked up and transferred onto a roller conveyor, into a pinch roller, then into the machine and feeding gripper.

Some material handling systems can begin with roller conveyors and be expanded as company needs change. Photo courtesy of HYDMECH.

Some material handling systems can begin with roller conveyors and be expanded as company needs change. Photo courtesy of HYDMECH.

• Flat–A good catch-all system that can be used with rectangles, squares, and rounds and can include scratch-resistant features that allow the material to slide without being in direct contact with the handling system’s metal.

• Lift and carry--trolley arms located throughout the material handling system lift material or bundles and place them on the roller conveyor. The arms eliminate friction that would be caused by sliding heavy material over the arms.

On the output side, options include belt conveyors that can include equipment like diverters and pushers to direct parts to various bins. A more sophisticated method is a servo-driven material gripper that can remove material from the saw and position it on a table that tilts one way or another to deposit the part into designated bins.

“We have also integrated drawbridges to allow trim cuts and remnant pieces to fall into a bin on the output side of the saw without interrupting the automation of a system. When a trim is cut, the drawbridge opens and the material being cut moves forward, which pushes the trim out so it drops into a bin beneath the drawbridge. The drawbridge closes and the finished material runs across the top,” said Suydam.

Workcells

“A workcell environment can be created where material comes in the front door, moves through the sawing process, and finished parts flow out the back door. Transfer arms and conveyor systems carry the product through,” said Arcaro. “An operator can see that several jobs are loaded in the morning and he doesn’t need to leave the workstation midshift to feed the machine.”

If a company isn’t ready for full-blown automation, he added, they can begin small and add capabilities when appropriate. “Our system allows you to start with conveyors and add or adjust size and complexity as projects, budget, or real estate changes.”

ROI

Suydam said, “Each shop has to factor its own yield into the equation when deciding on material handling. Say, for instance, you are cutting an aluminum piece every 5 seconds—that is a lot for an operator on the output side of the machine to handle. If you are down just 10 minutes to load another bar, you lose approximately 120 pieces of productivity in that short period of time. Over the long haul, that can justify adding material handling capabilities.”

Everyone qualifies for band saw material handling, said Arcaro. It’s just a matter of how large or complex of a system is needed and, of course, budget. “Nobody has ever accused us of selling him too large of a system, but some customers have been disappointed that they purchased too small without accounting for future growth. Choosing a material handling system comes down to operation for today and vision for tomorrow.”

A flat magazine stores multiple types of material as it waits to be moved to the saw. Photo courtesy of Behringer.

A flat magazine stores multiple types of material as it waits to be moved to the saw. Photo courtesy of Behringer.

Sue Roberts can be reached at sroberts@canadianfabweld.com.

Behringer Saws Inc., 610-286-9777, www.behringersaws.com

HYDMECH, 877-276-7297, www.hydmech.com

 

Once the Material Is Moving…

Including a digital positioner can improve overall cutting performance, add efficiency, and give each job the chance to add more to the bottom line.

According to Scott Brode, central regional manager at TigerStop, an automatic linear positioner paired with a band saw allows an operator to combine operations and to be more effective and efficient. Benefits are found in five key areas.

1. Setup time can be reduced to almost zero. “With a positioning system, an operator can go from cutting one length to another in seconds. There is no need to look around for additional jobs that are the same length to maximize a setup.”

2. WIP and inventory can be reduced. “Dynamic optimization or nesting software quickly and easily allows for the use of remnants or existing drops to be used on new cutlists. This eliminates the need to utilize a new piece of raw material.”

A material pusher like the HeavyDuty 2 can alleviate operator fatigue and increase productivity. Photo courtesy of TigerStop.

A material pusher like the HeavyDuty 2 can alleviate operator fatigue and increase productivity. Photo courtesy of TigerStop.

3. Accuracy can go up, rework down. “As an operator gets fatigued, it is not uncommon to mismeasure while setting a manual stop or misread a tape measure. A digital positioner is going to be accurate every time the measurements are keyed in. It’s not uncommon to see rework due to incorrect measurement reduced by 50 percent.”

4. Productivity can increase. “Using a digital positioner can easily increase productivity by 10 to 20 per cent over a manual system. Once the material is loaded on the tables the operator can stay in the cutting zone, reducing the inefficiencies of having to walk back and forth.”

5. Yield can jump. “Yield can go up because remnants from previous jobs can easily be used. Algorithmic programs will allow for the best utilization of drops, as well as raw material lengths, to complete the cutlist requirements. The guesswork of getting the best fit from the material is eliminated completely, with minimum waste of the material.”

TigerStop, 360-254-0661, www.tigerstop.com.

 

About the Author

Sue Roberts

2135 Point Blvd

Elgin, IL 60123

815-227-8241

Sue Roberts, associate editor, contributes to both Canadian Metalworking and Canadian Fabricating & Welding. A metalworking industry veteran, she has contributed to marketing communications efforts and written B2B articles for the metal forming and fabricating, agriculture, food, financial, and regional tourism industries.

Roberts is a Northern Illinois University journalism graduate.