Monitoring Quality throughout the Planer mill
Posted on December 18, 2017
Monitoring quality at the Planer mill is a task usually performed at the end of the production line, after all personnel and components have contributed their role in the production process. Simply set a pack aside, manually inspect it, and document any concerns. This is a very important task in the production process, but it can only take place after the production process is complete. Because of this, major quality flaws can potentially go unnoticed until it’s too late. This can be avoided simply by monitoring quality throughout the entire production line.
The Planer mill can be divided into 3 large sections: Infeed, Interim, and Outfeed.
The infeed consists of all components from the infeed package chain to the planer. In this area of the Planer mill, it’s more about contributing to optimal quality than it is about monitoring quality. Here are some steps that can be performed to help ensure optimal quality:
- Inspect the forks on the infeed forklift. Over time, forks will inevitably become marred due to rocks and machine support structures. If the damaged fork is bad enough, it can scar the bottom layer of lumber. Sometimes it could damage it enough to create down grading. Routinely grinding any imperfections on the forks can help ensure minimal damage to the lumber.
- The drop out moisture meter can not only affect quality, but production as well. It is the first line of defense against wet lumber. It can easily go overlooked and allow too much wet lumber to continue down the production line, or in contrast, drop out dry lumber. Calibrating this piece of equipment does not need to be done as often as other pieces of equipment in the production line, but it does need to be completed thoroughly. Inaccurate readings can make or break production and quality. Lumber temperature and ambient temperature are both contributors in the way the moisture meter detects moisture in the lumber. Confirming that the moisture meter is calibrated properly from time to time will save yourself from potential down time, as well as unwanted low-grade lumber.
- The planer operator usually has a check list of things to ensure proper quality, such as dimension control, finish, and eased edge radius. All of these things are tremendously important to the quality of lumber, but there are other things that can go under the radar at the planer infeed. Things such as crowder chain and pineapple speed to ensure proper feeding into the planer. Ensuring a “ribbon feed” of lumber into the planer can help reduce the risk of machine bite on the lead end, which is easy to go unnoticed by grader. Continuous ribbon feeding will not only prevent this, but it will also do its part to ensure optimum production. The planer operator can also help quality of lumber by turning boards with the wane side up. Most planers take more cut from the top head. If the wane is positioned to be cut by the top head, there is a better chance of that piece going to a higher grade.
The interim section of the mill consists of the grading area through the end of the sorter. This area is perhaps the most efficient area for monitoring quality and preventing any unwanted defects from making their way into packages that they should not be in.
- The graders bear most of the weight in this area. If there is an automatic grader in use, this frees up a lot of time for the graders to continuously monitor lumber quality. Routinely comparing random physical pieces on the grading line with the optimized solution can be a quick way to determine if there are any problems with grade-out and planer set-up.
- The round table or pull chain is the best place to see if any unwanted trims are taking place. Routinely checking blocks can reveal things such as length issues, machine bite, offset, and may other issues that can be hard to see on the grading chain. Advising round table employees to be observant of blocks with no defects and trending machine related defects can be beneficial to preventing trim loss and adding board footage to the sorter.
- By routinely monitoring the area after the trim saw, post grade saw defects can be easily spotted. Bad ends could mean a limit switch or photocell has moved out of place or quit working altogether. Uneven cuts, if occurring, are easy to spot in this area. If so, it could signal that a belt or saw needs to be replaced.
- Grade stamp printers and other stamp machines rely on ink, which depletes over time. A spot check during breaks and occasionally while running could prevent re-running packs due to no stamp. It’s a simple habit to adopt that could prevent hours of production time lost, as well as below-grade pieces in a pack due to the lack of a stamp.
The Outfeed area consists of the stacker, package maker, and the process of placing finished product in its appropriate place by the forklift drivers.
- The stacker, with all of its moving parts, can easily damage lumber. Ensuring that all hold downs have proper pressure, and the forks are ground down can prevent post grade scarring of lumber. This is also an excellent place for the stacker operator to be observant of mixed grades in any given pack and signal to proper personnel that there may be an issue up stream.
- The package maker is the last step before the packages get strapped. If all other monitoring is efficiently taking place, there shouldn’t be much for the package maker operator to notice. However, this isn’t a perfect world, and things slip through the cracks. This is an excellent area to monitor lumber length. If there’s too much variation in saw distances, the lumber length can be slightly offset. Usually it isn’t bad enough to affect the legality of lengths, but even the slightest difference can be aesthetically displeasing.
- The outfeed forklifts present the same issue as the infeed forklifts. The forks are prone to wear from rocks and chain-runner support. Routinely inspecting the forks can and will prevent marring of lumber.
- Ensuring that correct tickets are on the corresponding packages may seem like something that’s mundane or easy to put little thought into, but it is just as important as every other part of the process. Accurately ticketed packages are essential to package placement, delivering exactly what the customer has ordered, preventing value reduction, and last but not least…an entire pack of below grade lumber. All of this can be prevented by simple routine shed walkthroughs.
With all of this being said, you may have noticed a trending word throughout this blog. That word is “routine”. It’s brought up multiple times not only because it’s pleasing to the ear, but because it’s the most important habit to adopt when monitoring quality. Setting up routine quality monitoring procedures throughout every process of the mill can help lumber stay on grade, and provide a more attractive end product.
Timothy – Process Expert