Identifying Thermal Mass Problems In Paint Curing
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CAS Data Loggers
12628 Chillicothe Rd., Unit J
Chesterland, OH, 44026
Press release date: March 6, 2012
Grant OMK610 Oven Logger Kit Forms Complete Solution
CHESTERLAND OH - CAS DataLoggers recently supplied the oven datalogging solution for a manufacturer of commercial snow removal equipment which was experiencing periodic problems with the quality of their powder-coated parts. Their manufacturing line was designed to be flexible enough to allow for a mix of snowplows, plow frames, frame brackets and other parts to be processed on the same line. A single conveyor moved the parts through a pre-treatment area, a quick changeover coating booth, and then on through the curing oven and cooling area. However, in some cases, the finished parts appeared dull, and the company was also experiencing a high rate of field failures where the coatings would peel and flake. All signs indicated that these failures were related to incorrect curing of the powder-coated parts even though a check of the curing oven indicated that both temperature and time were within the coating manufacturer's recommendations. An oven logging solution was required to make a more detailed analysis and identify the problem, so management began searching for a complete kit with extreme durability, large memory and user-friendly data analysis software.
Management inserted a Grant OMK610 Oven Logger Kit into the paint oven, enclosed in its enhanced stainless steel thermal barrier providing maximum insulation safeguarding the datalogger against temperatures up to 250°C (482°F) for as long as 50 minutes. The kit's optional phase change insert was added to the barrier to absorb heat and extend operation at the above temperature to a full 100 minutes. The compact 6-channel data logger connected with a wide range of Type-K thermocouple probes and was designed specifically for through process and surface coating applications. The battery-operated datalogger stored up to 250,000 readings, and the logger directly printed out reports with no PC required in their production. These standard reports on all functions of the curing process gave proof of compliance of all the manufacturer's stoving requirements. The oven logger also featured sample rates of up to 8 samples/second and a USB interface to communicate with a PC for setup and download of stored data. The comprehensive kit included a carrying case, a quick-start guide, a set of batteries, and also offered optional fast-response and high-accuracy probes in clip-on, magnetic and combination types with models for both surface and air temperature measurements.
The kit monitored several batches of parts as they were sent through the curing oven. Once all the data had been collected, a graph of the part temperature against time in the oven immediately revealed the problem: the large moldboards, which had a high thermal mass, had not been in the oven long enough to completely cure the coating, resulting in the dull parts. Also, smaller parts with a lower thermal mass were being over-cured, resulting in coatings that peeled and failed prematurely. The solution was to process the parts in groups so that conveyor speed could be adjusted to get the optimal cure rate based on the mass of the product and the information collected from the data logger for each type of part, entirely alleviating the problem.
Additionally, the Grant OMK610 oven logger kit included FREE user-friendly PaintView setup and data analysis software, a spreadsheet-style software package exclusively for the paint and finishing industry. PaintView enabled storage of preprogrammed cure data and display of calculated cure percentages and also allowed easy setup and automatic data download from the logger into a meaningful measure of paint cure, offering users the choice between the Grant 'classic' cure or area integration cure analysis methods.
PaintView also provided rapid interpretation of results for advanced paint cure calculations and gave users graphic analysis of historical and online data along with advanced reporting. Users could easily view and control the logger status from one single screen and save all settings for reuse, while a security function protected all data and setup configurations. A database could be built containing different paint types from various paint manufacturers, with data exported into Excel(TM) or as a CSV file for customizable data analysis.
The manufacturer's production of dull parts and high field failure rates were immediately corrected following installation of the Grant OMK610 Oven Logger Kit, having identified the curing problems. Additionally, the comprehensive system assisted in production quality control and led to lowered operating costs, providing everything needed for paint oven temperature profiling and paint cure calculations in one easy to use and convenient kit. The manufacturer consistently met their own specified cure parameters and maintained a specified level of cure to ensure repeatable quality and maximize oven usage and throughput.
For more information on the Grant OMK610 Oven Logger Kit, other versatile Grant dataloggers, or to find the ideal solution for your application-specific needs, contact a CAS Data Logger Applications Specialist at (800) 956-4437 or visit the website at www.DataLoggerInc.com.
CAS DataLoggers, Inc.
12628 Chillicothe Road
Chesterland, Ohio 44026