A Conversation with Don Friar- CPM’s Operations Manager-
about conveyor simplicity or lack of complexity
- When did you begin to intentionally design systems for more simplicity
Direct From our Website:
This starts with being as simple as possible. Simplicity requires better upfront engineering.
While some complexity will always be needed to get our systems to perform best, leaning
toward simplicity reduces initial cost, improves reliability, and simplifies maintenance and repair.
“Better Designs, Better Engineering, Better Conveyor Systems”
We started our careers as service people, fixing everything conveyor and controls. We saw over
and over again systems designed by some of the biggest and best vendors that were over complex
and technical. We have no issue with needed complexity and technical innovation. It is the excess
and unnecessary use of those things that we got frustrated with. Almost every technical discipline
you introduce into your system increases cost, reduces reliability, and widens the expertise needed
for service personnel. Worst of all is when you rely on uninterrupted flow of you r production or
distribution material handling systems and the system is down. Then you find out the one guy that
can fix your system is a couple of days out.
So we have made it our mission to use all the technology we need to but to lean towards simplicity.
Surprisingly, this takes a greater effort up front, but it is always worth that effort.
- Was there a moment or situation where this began to seem like a clearly
different approach from what is standard or the norm?
I’m not sure there was a moment. It was more of an evolution over time. You come across a service
or repair situation and realize this could have been done way simpler, cost less to purchase and
install and would have been much easier to fix. We love those systems engineers, and we need them
for sure, but we have to remind them that just because you have a shinny new technology in your
pocket to use does not mean every application needs it.
Don’t get me wrong, PLCs, frequency drives, communication systems, scales, speed controls, lifts,
diverts, sorters, robots, and a host of associated equipment’s like wrappers, strappers and tape
machines are all parts of modern material handling systems and we use them all. What I am saying
is as you work through the design of a system, bias your thinking and lean at simplicity to minimize
over complexity.
- What are a few of the costliest mistakes you have seen made in conveyor
design? Why were they so costly?
There are so many…
One comes to mind that we are working on fixing right now. This distribution facility was installed
by others and we have been doing service and maintenance there for 5 or 6 years. They installed
line shaft accumulation conveyor on their 3 level pick lines and their two 18 station pack lines. The
mistake was using line shaft conveyor. Without getting too in depth, line shaft conveyor is a poor
choice here because this system runs 24 hours 3 shifts and there is little tolerance for down time
and line shaft conveyor is very time consuming to repair and is not designed for running 24/7. This
has been a huge frustration from day one and could have been avoided by thinking through the
application up front. Ironically, the fix for this problem is going to cost less to install today than the
wrong equipment costed to start with.
Another one is a belted spiral incline. These things are a maintenance nightmare. It is a day long process
for a couple guys and those belts cost upwards of $20,000 each. It is very expensive and time consuming
to repair and is repair prone. The correct application would have been a slatted spiral. They said they
chose the belt so it would have the traction to carry boxes up the incline. The slatted spiral can use rubber
topped slats to cover that application. If a slat is damaged, you stop the conveyor, remove one slat
(no tools required) and snap in a new slat (4 or 5 minutes) and you are back in operation. I said ironically
before but the same situation here is that the solution costs less than the original mistake.
- What are some areas of conveyor systems and peripherals that are worth extra
cost? Why are they worth the extra cost?
The first one that comes to mind is frequency drives. They cost a little more that the old standard contactor
relays used to start conveyor motors. The problem with the contactors is they start motors “cross line”. That
means the motor goes from 0 to 1800 RPM in the blink of an eye. The problem with that is all the inertia of
the conveyor, belts, rollers drive chains, sprockets, bearings, gear reducers and couplers get hammered every
time you turn the system on or off. The solution is using a frequency drive that soft starts and stops the conveyor.
This not only relieves the trauma to the system, but it is also useful on an incline belt. If you start too hard, things
may tumble down the belt.
Another is idle system shutoff. MDR conveyor does this automatically but it can be incorporated in any conveyor
to shut down if the conveyor sees no traffic for say 20 or 30 seconds. Many times I have walked into a manufacturing
or distribution facility and miles of conveyor is sitting there grinding away it’s useful life and burning energy while
the staff is on lunch break or a simple belted incline or decline that sees package in waves and spends most of it’s
time just running. We can easily design them (or upgrade them) to shut down when there is no traffic and automatically
restart when traffic arrives. This saves wear a tear, energy consumption and contributes in no small way to ROI.
- How do you determine if a given design is the simplest / best way to solve a client’s problem?
This mostly comes down to experience and probably more specific experience in conveyor service, maintenance,
and repair. It is the experienced guy under the hood of the new car that could suggest a better way to do a few things.
I think that is what sets us apart. We have been fixing and maintaining conveyor and their systems for many years
and we see wrong applications or bad ideas or over complicated technologies. The guys that spend all their time
designing and laying out conveyor for companies that have them in that job exclusively, unfortunately never get
to but their knuckles or get out of bed at 3am to fix poor designs or decisions. To more directly answer the question,
we determine if a design is simple enough by knowing from experience with service if it is the right choice.
We also listen to the customer. I have a current customer that we designed a sortation system for that involved a
recirculation loop for sorting people. The sorters currently picked their products from the conveyor as it went by.
If they miss something, it went to “jackpot” where someone would then have to bring it back to them manually. We
thought a better system would be to build a recirculation loop so if a product were missed, it would come by for a
second opportunity. The customer did not want that because he said in his experience, this would make the sort
workers lazy and inefficient, knowing that if they missed something, it would come back to them. You might argue
that is a management problem, but it was what he wanted, and we had never considered that as a problem before.
- What are a few of the areas that simpler designs save the most in upfront CapEx cost?
I want to be careful here because I am concerned that we are making a general statement that simpler is better.
Sometimes it is, but maybe we should say it should be as simple as it can be while still delivering everything needed
for the application? Can we save CapEx money by being simpler? In many cases yes, but we need to remember that
simpler often means using less technology. This is where CapEx savings can happen along with a company that keeps
a lean overhead (a shameless self-promotion for CPM Conveyor LLC). If however that technology is needed for the
application, it should not be designed out just to be simpler. What we really want you to know is that we will always
look for ways to minimize complexity while completely satisfying the application. This approach will always give you
the best “bang for your buck” on the CapEx side and will continue to deliver benefits as the system begins to run up the miles.
- What features or technologies are the worst energy consumers?
I’m not sure about features or technologies that are inefficient. It is usually features and technologies that help us
be efficient. When it comes to conveyor itself, the most inefficient is slider bed belts. The friction of the belt on the
slider bet is pure friction. It is the least expensive type of conveyor to buy but the most expensive to operate.
- What features or technologies are the most energy efficient?
The biggest one I already mentioned and that is “no traffic shut down”. It is very simple to do. The up front of upgrade
cost to install it is small and the ROI is very short even for installing on existing systems. We simply use a photo eye to
monitor traffic and if we don’t see any for a chosen and adjustable amount of time (say 30 seconds), the conveyor shuts
off and when traffic does arrive, it simply turns back on. We generally use this technology in conjunction with the
frequency drives for motor control so we soft start and stop the conveyor to avoid excess wear and tear on the drive system.
Another technology that improves efficiency is MDR conveyor. MDR is “Motorized Driven Roller” There is no motor,
chain, gear reducer or coupler. The roller is the motor. It is a fascinating technology. Each powered roller turns a
number of adjacent rollers and runs on 24vdc low voltage. This is a perfect for accumulation systems. These systems
can also be programed to shut down on no traffic. Another interesting feature of this technology is the rollers will stall
under excess load. You can stop them with your hand. They are a huge safety innovation. If a person were to get tangled
in the conveyor, it will simply stall. In many jurisdictions using MDR eliminates the need for an E-stop switch.
- What can cause what used to be an energy efficient system to become highly inefficient?
Can this be prevented? When is it time to replace the system?
The only significant answer here is lack of proper lubrication. This can happen if the customer doesn’t have a proper
system maintenance program in place. CPM Conveyor provides this service. (another shameless self-promotion for
CPM Conveyor). If any moving or rotating shaft or drive chain is deficient in lubrication, it will get hot and hard to
turn or move. This is of course inefficient power wise, but it is also destroying parts of your conveyor. Those parts will
eventually need replaced. Yes, this can be prevented with a proper maintenance program. There are two primary reasons
for you to see my service department, maintenance, or repair. Maintenance is what it sounds like. It is to “maintain”
your conveyor in a healthy and operational state. Repair is also what it sounds like. It is to fix broken stuff. We use
maintenance to minimize repair work.
When is it time to replace a system? When it can no longer satisfy your operational requirements. If you can not get the
job done with your current system, it is time to consider replacing it. Another reason to replace a system is when the system
has so many miles on it that you spend too much time down with repairs.
- What are the top maintenance tasks that must be performed regularly on a conveyor
system and material handling system?
We just touched on one of them and that is proper lubrication of moving or rotating parts and bearings. We also do
general inspection for loose fasteners, belts that are not tracked, rollers not turning, broken frames, fork truck damage,
air leaks, over heated motors, and anything else that stands out as an issue. The results get reported to the customer in
a PM Report, so the customer understands the condition and health of their complex and expensive systems.
- Are there any common areas of automation / robotics that are unnecessary but
frequently used anyway?
Not frequently in the use of robots. Roots are still pretty expensive, so most customers look over the applications pretty
well before going there. What can happen there is the wrong robot can be used for the application. And that is the rest
of the answer too. It isn’t so much that automation is used when it is unnecessary, it’s more that the wrong automation
or technology gets used and it doesn’t fit the application very well and the results are mixed.
- How do overly complex conveyor and automation / robot systems add to maintenance
costs? How does this change as the system gets older?
I think the question gets away from my message of simplicity a bit. It isn’t so much a question of over complex because
sometimes complexity is needed. Although there are systems that are built over complex, the bigger issue is usually that
bad choices are made for the application. The automation and controls can be too complex. Maybe a PLC is used where it
is kind of a wash whether one is needed or not. If you have that decision, I would go without because initial cost is lower,
you avoid programming cost and a less qualified person will be able to service it if it needs attention.
I don’t think this issue gets worse as a system gets older except when wrong application choices were made tolerance for
increasing maintenance may be low.
- Do any of these repair / maintenance questions change if you if you are considering
someone that has in-house maintenance teams vs contract maintenance teams?
If so, what changes?
We are a contract service and maintenance team so no bias here… LOL Seriously, when it comes to in-house service teams,
there are many different levels of ability. If a customer has no in-house service we make ourselves available to them for
anything they need. If they do, we take on the roll of support team. We always work at the customers pleasure, so we work
to help them cover their need, what ever that is. As far as what changes, it depends on how capable the in-house service team
is. Sometimes we do the PM work and send the customer a PM report and the customer in-house service team will any needed
repairs. Sometimes it is the other way around and the in-house guys do the PMs and have us in to do repairs. In any case it is
good to have outside eyes on your systems as partners with your in-house guys. This gets the broadest perspective on conveyor
and system maintenance.
- In your opinion, how much automation is too much automation? If you had to give a single
rule-of-thumb for this that every DC and manufacture in the world had to follow for the
rest of time, what would it be?
Again, I want to through a little water on this idea that there is too much automation going on. The argument is simplicity
vs complexity. Many times complexity comes from making a bad choice of technology or equipment for the application. So
lets answer the question but call automation complexity.
I would say this as a rule-of-thumb: Understand the customer need and the application and then go back and make sure
you understand the customer need and the application… It is important to not short cut this process. Once you have that
worked out, make sure again. Then design a system that is as simple as possible that fully satisfies the application.
- What should your clients do every month / quarter / year to ensure that they are getting the
maximum productivity out of their system? How do they know if they are achieving the max productivity?
This is a hard question to answer because there are so many options in conveyor and handling systems. Each system is
different but the one thing they all need is maintenance weather that maintenance is handled by a contract provider like
CPM or an in-house team or a combination of the two, a properly designed maintenance program is just as important as
selecting the right equipment, automation, and controls for your system. That is why we are here. The way you know if you
are getting maximum production from your system is by getting a detailed report of the health and well being of your system
from a properly executed PM program.
- Why have simpler systems ended up being more productive in the past?
I don’t really measure conveyor performance in productivity. I do measure some based on efficiency, but I would say
mostly I measure its performance on whether it fits the need and application. If it has a long durable life span, fits the
need and application of production, has high reliability, is simple enough for the service people to repair and maintain
without significantly interrupting production, I call that a win.