OEE goes paper-free
30 Oct 2008
Overall equipment effectiveness (OEE) is widely used as a key performance indicator (KPI) by process operators who need to measure how effectively their manufacturing operation is running in terms of availability, performance and quality.
However, a problem with most OEE data capturing systems is that the time taken to collect the data is disproportionate to the time available to analyse it, according to Chris Steel, continuous improvement manager at Evonik Degussa's Seal Sands site.
"By the time you have collected all the data involved and analysed it, you are on to the next month. So you never get to the point of dealing with all the information." explained Steel. However, he believes Evonik has devised a wireless-based solution to this dilemma.
According to Steel, the operation last year started looking at what the barriers to achieving effective OEE actually were. The company, he noted, had previously set out with a paper-based system with charts and codes for when and why things were running or not - but with limited success.
This highlighted a need to move to a computer-based data analysis and monitoring capability. The target, said Steel, was to achieve real-time monitoring of OEE across the site's four production buildings, including the Zone 1 hazardous areas.
The company initially considered installing several fixed LAN Ethernet connection points, but the installation costs for this type of infrastructure and lack of future scalability ruled this option out. The site was also constrained by the lack of a suitable IT infrastructure for the manufacturing area and issues with installing equipment within Zone 1 operations.
Steel and his team, instead, opted for a wireless network from Extronics, which employed the vendor's Meru-powered iWAP101 802.11a/b/g WLAN access points. The intrinsically safe network is centrally managed and controlled via a single-channel architecture, which is designed to provide robust WLAN for heavy metal environments.
The overall project started in the second quarter of 2007 with talks about the system and inputting of data for every building and every single piece of critical equipment. This, said Steel, involved 74 bits of kit. The electronic system went live on 1 Jan 2008, with eight antennae devices giving virtual wireless capability on every floor in each production building.
The project represented an investment of just over £100,000, which included £3,500 for a wireless survey across the entire site. "Because of the chemical environment and all the girders out there, we knew that to get something to work that was wireless was going to be very difficult. From the survey, we now know where we can have wireless coverage, across the site," explained Steel.
Another challenge was getting the operators to adapt to the new system, the CI manager continued. "As with all these systems there can be lots of resistance from production if you ask them to fill in forms etc. We wanted them to buy into the solution, which we did through a Masterclass to introduce OEE out on the plant. That way it became their system."
The process was helped by the ease of use of the system. The control terminals, said Steel, are very simple "just like a PC on a stick," while the screens are touch-sensitive, which is quite important for the operators on the shopfloor.
"Then, and what really makes this future-proof, is the use of terminals out in production with the server unit sitting in the admin buildings, so if we want to upgrade later we just install more terminals."
As a reference site for Extronics, Evonik is soon to trial a battery-powered version of the system, which can be charged by plugging it into the ring main for 12 hours. This will enable the company to monitor further equipment, such as the filters and the dryers, which can slow the process and impact OEE.
The WLAN network is supported by a software package developed in-house by Evonik Degussa. This allows process operators to log faults and other critical information relating to the production equipment and gives instant feedback on equipment performance.
Plant operators have a choice of day-view or shift-view and codes to indicate the reasons for downtime. The touch-screen options also allow them to select the product and input data every hour, for example to indicate changeovers or cleaning.
Data from the wireless network is fed into the company's business management system to provide managers with at an analysis of production. This includes generating a breakdown of performance by batch times, as well as continuous improvement reports. There is also a capability to split the hourly production analysis into 15-minute slots.
According to Steel, one of the key pieces of information is 'previous best demonstrated time', which indicates the best production runs, including an analysis of the uptime and downtime. The system also flags up where the limiting, or bottleneck, vessels are, while a trend button will track downtime and uptime across the site.
"The information starts to tell us how to balance production. We can now get our engineers to really home in on where the opportunities for improvement are, and target issues that are causing downtime on any process," said Steel.
The system can also break down production time into different activities. This enables the company to analyse different step groups, such as total batch times with most variation, and focus in on that.
"Rather than just spending time measuring our OEE, we are now able to involve our people and concentrate our efforts on improving specific areas identified by the analysis tool," concluded Steel. "A lot of savings are about just being more consistent in the way we do things in the critical step groups."
However, a problem with most OEE data capturing systems is that the time taken to collect the data is disproportionate to the time available to analyse it, according to Chris Steel, continuous improvement manager at Evonik Degussa's Seal Sands site.
"By the time you have collected all the data involved and analysed it, you are on to the next month. So you never get to the point of dealing with all the information." explained Steel. However, he believes Evonik has devised a wireless-based solution to this dilemma.
According to Steel, the operation last year started looking at what the barriers to achieving effective OEE actually were. The company, he noted, had previously set out with a paper-based system with charts and codes for when and why things were running or not - but with limited success.
This highlighted a need to move to a computer-based data analysis and monitoring capability. The target, said Steel, was to achieve real-time monitoring of OEE across the site's four production buildings, including the Zone 1 hazardous areas.
The company initially considered installing several fixed LAN Ethernet connection points, but the installation costs for this type of infrastructure and lack of future scalability ruled this option out. The site was also constrained by the lack of a suitable IT infrastructure for the manufacturing area and issues with installing equipment within Zone 1 operations.
Steel and his team, instead, opted for a wireless network from Extronics, which employed the vendor's Meru-powered iWAP101 802.11a/b/g WLAN access points. The intrinsically safe network is centrally managed and controlled via a single-channel architecture, which is designed to provide robust WLAN for heavy metal environments.
The overall project started in the second quarter of 2007 with talks about the system and inputting of data for every building and every single piece of critical equipment. This, said Steel, involved 74 bits of kit. The electronic system went live on 1 Jan 2008, with eight antennae devices giving virtual wireless capability on every floor in each production building.
The project represented an investment of just over £100,000, which included £3,500 for a wireless survey across the entire site. "Because of the chemical environment and all the girders out there, we knew that to get something to work that was wireless was going to be very difficult. From the survey, we now know where we can have wireless coverage, across the site," explained Steel.
Another challenge was getting the operators to adapt to the new system, the CI manager continued. "As with all these systems there can be lots of resistance from production if you ask them to fill in forms etc. We wanted them to buy into the solution, which we did through a Masterclass to introduce OEE out on the plant. That way it became their system."
The process was helped by the ease of use of the system. The control terminals, said Steel, are very simple "just like a PC on a stick," while the screens are touch-sensitive, which is quite important for the operators on the shopfloor.
"Then, and what really makes this future-proof, is the use of terminals out in production with the server unit sitting in the admin buildings, so if we want to upgrade later we just install more terminals."
As a reference site for Extronics, Evonik is soon to trial a battery-powered version of the system, which can be charged by plugging it into the ring main for 12 hours. This will enable the company to monitor further equipment, such as the filters and the dryers, which can slow the process and impact OEE.
The WLAN network is supported by a software package developed in-house by Evonik Degussa. This allows process operators to log faults and other critical information relating to the production equipment and gives instant feedback on equipment performance.
Plant operators have a choice of day-view or shift-view and codes to indicate the reasons for downtime. The touch-screen options also allow them to select the product and input data every hour, for example to indicate changeovers or cleaning.
Data from the wireless network is fed into the company's business management system to provide managers with at an analysis of production. This includes generating a breakdown of performance by batch times, as well as continuous improvement reports. There is also a capability to split the hourly production analysis into 15-minute slots.
According to Steel, one of the key pieces of information is 'previous best demonstrated time', which indicates the best production runs, including an analysis of the uptime and downtime. The system also flags up where the limiting, or bottleneck, vessels are, while a trend button will track downtime and uptime across the site.
"The information starts to tell us how to balance production. We can now get our engineers to really home in on where the opportunities for improvement are, and target issues that are causing downtime on any process," said Steel.
The system can also break down production time into different activities. This enables the company to analyse different step groups, such as total batch times with most variation, and focus in on that.
"Rather than just spending time measuring our OEE, we are now able to involve our people and concentrate our efforts on improving specific areas identified by the analysis tool," concluded Steel. "A lot of savings are about just being more consistent in the way we do things in the critical step groups."
