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Does Your Preventative Maintenance Approach Need Updating? Maintenance Tips for Automated Nailing Machines
Is your preventative maintenance program or lack of one costing you money. Learn some strategies for how to keep things running well and improve your maintenance program for automated nailing machines.
By Chaille Brindley
Date Posted: 7/1/2013
If you are like many other pallet companies, your preventative maintenance approach may be an afterthought or inadequate according to Paul Bailey of GBN Machine. Having designed and built all sorts of automated nailing machines over the last 20 years, Bailey is one of the sharpest minds in the industry when it comes to pallet systems. He recently sat down with me to discuss why preventative maintenance can save you money in the long run. He offered strategies for how you can improve whatever approach you are using no matter the age or type of machine.
Pallet Enterprise: Over the years, pallet machinery has changed a lot. Describe some of the changes that you have seen take place in terms of the guts of the machines over the last 20-30 years?
Paul Bailey: The electrical systems changed, going from relays to programmable logic controllers (PLCs). Obviously you had physical contacts in relays that would burn out over time. When there was a problem, you had to go back in and trace the wiring and test or replace the contacts to discover why a machine would work for an hour and then wouldn’t work. The initial PLCs were very large and kind of unwieldy. The programming software and interfaces weren’t that great. But through the 90s, all the hardware and software improved. You could use your laptop to troubleshoot and program. It makes the entire process much easier. The PLCs themselves have gotten smaller and smaller and if you have a problem, you can look at lights on the input or output cards to visibly see if the switch or valve etc. is on or off. You can do more things with the new PLCs. With the old relays, you had to get either pneumatic timing units or electric timing units, which used physical contacts that could get dirty or even burn out over time. Now you have solid state outputs. Things can be done much faster. It’s all done on a computer screen now and exists in the memory of the computer. You can do a whole lot more with less space.
The downside to using PLC’s is that the PLC manufacturers are struggling to keep up with new computer operating systems, such as Windows 7 or now 8 which means that the end user or OEM has to continually upgrade equipment to keep up as well. Another issue is keeping machines compatible with the newer software versions the OEM’s are releasing. For instance, RS Logix 5000 was compatible with Windows XP through version 19. The name of the software has now been changed to Studio 5000 and version 21 and above is compatible with Windows 7 and above.
Pallet Enterprise: What is the typical maintenance checklist for an automated pallet nailing system? Is there much variability in what needs to be maintained from unit to unit?
Paul Bailey: The maintenance checklist depends on the machinery in use and the number of shifts that you are running. I usually send a recommended maintenance sheet with the machine in the manual. It all starts with regularly inspecting your machine instead of just running it day-in and day-out. You have to look at your bearings, electric eyes, cables, cords, wiring, sprockets, chains, etc. You have to keep up with the preventative maintenance on those parts of your system.
Our machines are very robust, and people tend to run them until they break. Then they put them back into service with a makeshift solution that works for a while until the machines really break. And then the problem is repaired correctly or we are called in to help fix the problem.
As far as a checklist, I recommend that companies daily clean or blow off the machine, especially electric eyes, motor and gear boxes, chain tracks, and nail picks; so if there is an issue beginning, you can see it. We went down to install a new machine at a customer location in the South. This company had previously installed an Excalibur a year earlier. There was so much sawdust under the machine that where the turner turns the pallet over, you couldn’t see the cylinders. The sawdust was 18” deep in there. We filled a container with sawdust so that we could get in and grease the points at the bottom of the turner cylinders.
The machines tend to get ignored as long as they are running. A lot of this is caused by the poor economy where everyone is getting leaner. Maybe you need four maintenance guys, but you only have one on staff. He spends all his time putting out fires and doesn’t have any time to do preventative maintenance. In times like this, some companies depend on the equipment to run with little or no maintenance until they can get the time to shut the machine down to do it. As a manufacturer, you have to take this into consideration when designing a machine, but all machines need maintenance sooner or later.
Of course, you could (and many companies do) train the operators to do some basic maintenance and inspection. Some companies do that by cleaning up the machine regularly. Everybody does it differently. Look to monitor and maintain pieces of the machine that get used more than other areas, such as stringer feeding mechanisms that operate three, four or five times per pallet compared to a turner that runs one time per pallet.
Pallet Enterprise: What is the one maintenance chore that gets ignored the most and why?
Paul Bailey: Preventative maintenance is easy to ignore. You really should look at the machine every week or so to see what is wearing out and what needs to be replaced. Too many companies are only discovering that there is a problem when the machine breaks or stops functioning. For instance, a gear box on a chain or roller conveyor seems like a little thing with an electric motor hooked to it. But there is oil in that box. And if it gets a leak, these don’t have a lot of oil in them. We are talking a maximum of one to two pints of oil. One small drip over three months and all that oil is gone. Now, you have a busted gear box that will cost you $600-$1,000 each to replace. There are many parts that have lubricants in them that are sort of out-of-sight.
In the pallet stacker, there is a jack scissor. There are grease fittings at every shaft and rotating point in that jack scissor as it goes up and down. But because it is under a stack of pallets and is in the middle of the stacker, people tend to leave that area alone. I recently had to replace a few bushings in one of those and it looked like a grease gun had never seen those fittings since it had left the factory 13 plus years ago. If the shaft wears through the bushing into the surrounding steel, you can’t fix the problem with a new bushing and shaft. Now the scissor mechanism has to be removed from the machine and repaired or worse, replaced.
If you read the manual, it has pictures of the grease points and how often they should be greased. Too many maintenance guys just walk around a machine and grease the points that they can see. You need to check the manual to make sure that you don’t miss key areas that are hidden, especially if they are between chain tracks or in the middle of or under the machine.
Pallet Enterprise: What is the best strategy you have seen for setting up a good maintenance program?
Paul Bailey: Many companies have piece work and bonus systems for operators of machines. One suggestion is to set a bonus for the maintenance personnel. Maybe a bonus each month for machines that have no down time or reductions in emergency part replacement costs. This gives employees an incentive to really look at a machine and make sure they don’t miss critical areas. Does this area have too much play in it? Is that bushing taking grease or is it coming out all around the fitting and there is no grease going into the actual bushing or bearing.
The problem is that while some companies do have maintenance programs in place, far more companies do not. Most of the time, a worker just services areas that they can see.
A good strategy is to get the manual for the machines you have and to check and see what preventative maintenance is suggested. Then make up a checklist and chart to ensure that it is done on a regular basis based on your usage of the equipment. Management may want to review the manual with maintenance employees to see that all the critical areas are covered. Less critical components can be serviced less frequently. We usually suggest weekly, monthly, six months and annual checklists.
Pallet Enterprise: What other maintenance pitfalls are you seeing companies experience?
Paul Bailey: A big one is not allowing time to do maintenance because the focus is always on production. Machines may be running at peak production five to six days a week. And at a lot of places unless the equipment breaks there is no preventive maintenance allowed on it. I have had this conversation hundreds of times over the last twenty years. Maintenance guys complain that they aren’t given the time to properly maintenance the machines because there is always another load to get out. One alternative to doing the maintenance during the week is to have the maintenance done over the weekend, but you have to be willing to pay the person for the overtime and find someone who is willing to come in on weekends.
Pallet Enterprise: Can you explain the real cost to benefit ratio of preventative maintenance versus simply reacting to problems as they occur? Does preventative maintenance really save money over time?
Paul Bailey: I think it does. When the machine breaks down, you are either going to build the load by hand or you aren’t going to get the load out. This is especially important in today’s “Just in time” economy. Not many companies keep inventory for customers like they may have fifteen years ago. Now you have a customer that is unhappy with you. And this could cause you to lose customers. If you do preventative maintenance you could have a part brought in via ground delivery which costs much less than express shipping on a heavy part that could run $300-$400. Shipping costs are crazy.This strategy relieves your company to obtain parts just-in-time to keep the machine from ever going down in the first place.
If you have a machine that needs a very heavy part that can’t be shipped via UPS or FedEx, then, the part has to be shipped LTL, which will take three, four or more days to deliver. Now, your machine is down several days. What does that do to your customers and your profitability for the week? The loss of production can be a key concern to consider.
Pallet Enterprise: Explain some of the pitfalls and things you need to know about moving a machine.
Paul Bailey: Moving a machine is always difficult. Most of the time, unless you have a really top notch person doing it the machine may not run as efficiently as it did before. The person moving the machine must take measurements between each part and make sure that everything is reinstalled, square, level and anchored securely to the floor.
In older machines, all the wiring was done point-to-point so you have a bundle of wires and many pieces of liquid tight, seal tight or conduit that went into each box. And all of those wires terminated in that box at a different place. Now we use plugs and hydraulic quick connections so moving a machine is not as hard in terms of connections and rewiring everything. But the biggest problem is making sure that piece of equipment is level and square when you put it back together again. Gaps between the different components need to be the same as they were before that machine was taken apart.
You need to take good notes and a lot of pictures about where everything belongs and how it all fits together before and as you take apart the machine. The other problem is that you may be putting this machine on a floor with a valley in the middle of it or possibly two different levels.
We recently talked to a customer who was buying a used machine from the West Coast. They wanted to put it on asphalt, which won’t hold a concrete anchor. The only way to do that is to construct rods that are driven down through the Asphalt into the ground or construct a steel framework that connects the entire machine together. Shims that level the machine would have to be welded to the machine to prevent them from moving around or simply coming out. That is a much harder installation than installing a machine on concrete.
We can come in and help a company disassemble and move a machine. Many times they prefer to do it themselves. But having someone who is knowledgeable of the machine can help make
sure that it runs properly when moved and reassembled. You need to take detailed notes if you are going to do this yourself.