Data collection: Improving efficiency on the plant floor
We need to breathe life back into manufacturing! I realize that the answers to manufacturing’s problems are not simple or straightforward. The complexities of a global economy along with the thirst for constantly increasing profits and stock prices has forced many companies to change their ways of doing business. Having worked for the past 26 yr in the industrial automation market and coping with these roller-coaster conditions, I have some suggestions that can help manufacturing improve its efficiency.
Improving plant efficiency
Throughout this downturn, many larger companies have invested heavily in lean manufacturing, quality and continuous improvement programs such as Six Sigma and kaizen, as well as software tools like ERP, PLM, and other e-business products. Their ambition was to boost performance and profitability. These approaches have allowed many companies to streamline their workforces, increase productivity, reduce inventory, manage assets, and cut lead times. Despite these high-tech implementations, companies still battle manufacturing inefficiencies.
While many companies think they are doing all they can to work smarter, some simple concepts have gone largely unnoticed. Two things that can immediately impact a company’s bottom line and improve efficiency are information and teamwork (I and T) — not to be confused with information technology (IT).
Plant floor information
My definition of information is plant floor data collection. While many manufacturing firms have invested millions of dollars on their front-office operations, some have virtually ignored their factories and the people who are responsible for managing and maintaining them.
Having access to plant floor information provides many benefits for everyone working in a manufacturing facility. Faced with having to do more with less, some plant personnel may say they already have information overload. However, it is shocking how little useable data collection is done in manufacturing plants.
Many companies use human-machine interfaces (HMIs) or programmable logic controllers (PLCs). But these are not plant floor data-collection remedies. Real plant floor data collection requires storing many machine and process parameters continuously for a very long period of time. These parameters could number into the thousands. This organized collection of critical parameters is called a data historian.
HMIs and PLCs not only enable operators to run manufacturing processes, they also help facilitate the flow of these process and machine parameters to plant floor data collectors. But HMIs and PLCs are not designed to be data historians. Using a data historian with plant floor data collection makes all the data available when it is needed without flooding you with unwanted information.
How does data collection facilitate efficient manufacturing? First, it allows you to monitor the quality of your product by viewing or analyzing the process parameters under which it was run. Imagine being able to modify your parameters, such as glue consumption, heat, pressure, etc., and improve the results of the product against past production runs. Consider being able to pinpoint the process parameters that caused a defect to appear in a customer’s shipment several months ago.
Manufacturing processes can be very complex and require deeper analyses than most plants do today. Many companies log how long it takes to produce a product and which machine made it. But logging this information does not explain why a product does not meet specifications. Some companies are using process parameter data collection to improve quality, but many manufacturers do not have this capability — nor have they thought about it. Traditionally, software that performed these plant-monitoring functions was extremely expensive. However, programs that are user friendly and affordable are becoming available.
Another vital benefit of real-time, continuous data collection is downtime reduction. Obviously, a manufacturing company needs to keep manufacturing; downtime is lost income. Machines do break, despite preventive maintenance efforts and well-organized work orders. A plant can have the most sophisticated front office or CMMS software on the market, but if it can’t monitor critical machine and process parameters, the machines won’t keep producing.
Whenever a plant can minimize or eliminate downtime, the savings go straight to the bottom line. Using data collection to monitor and archive critical machine parameters and key points of operation enables maintenance technicians to pinpoint problems quickly. Any function controlled by a PLC, or parameter measured by PLCs or process controllers, can be monitored and/or archived. Push buttons, limit switches, motor currents, line speeds, and many other machine parameters can be saved in data historians to be used as troubleshooting tools.
Many of us have had the unpleasant experience of being called in at 2 a.m. because a line was down and getting “I dunno” answers to our troubleshooting questions. The HMI is often filled with obscure fault messages and usually not tracking the parameters we need to analyze. Sometimes workers can misinterpret what happened at the time of failure, and inadvertently can cause machine failure. Imagine being able to retrieve in a matter of seconds the machine and process parameters for the last several hours up to the time of failure.
One company’s success
PolyOne Corp., Burlington, NJ, has saved many hours of downtime at its vinyl plant by using data collection. The company has reduced maintenance calls from hours to minutes by using real time and historical data collection. It uses data collection as a proactive maintenance tool by watching key points in its line for potentially damaging changes like high bearing temperature or motor current. It studies actual data to determine when maintenance or shutdowns should be done. It has implemented maintenance training using its own data collection examples. Even operator errors are reviewed with production personnel — not in a punitive manner but to train workers and improve performance.
PolyOne’s use of data collection has helped to improve operator efficiency and gives engineering valuable process data. Jim Wright, plant electrical engineer at that facility, states that data collection “gives you all the facts so that you can make better engineering and maintenance decisions.” At this site, engineering, maintenance, and production have worked together using data collection to improve the plant’s efficiency.
PolyOne’s teamwork approach using plant floor data collection and implementing new projects demonstrates that all groups within a facility can break down the age-old barriers among departments and improve efficiency making them more competitive — keeping manufacturing alive.
|Ron Iannacone, President, Automation & Control, Inc. and Factory Intelligence Network (FIN), LLC, West Berlin, NJ, has spent more than 26 yr in industrial automation. He can be reached at 856-767-1400 or email@example.com|