Redwood Plastics and Rubber offers a series of six molded polyurethane inserts for SN bearing systems. Part numbers R-1150 to R-1155 cover bores 1-15/16″ to 3-15/16″ but what if you have a larger bearing? The news is good as we can absolutely manufacture larger sizes! We just need a part number for the original bearing system. Fair warning that these are custom machined solutions vs. molded solutions meaning the per-piece cost will be substantial. If you think you would be using the inserts more often then you can discuss the creation of a tooling fee and what that would cost.
Recently we took part in a large expansion of one of our customer’s facilities and Redco plastic solutions were in all of the new machinery; however, for a new sorter our plastic sprockets had been declined in favor of a less expensive steel option. This is, of course, the customer’s choice but there were already clear signs of wear on the sprocket and they were noisy making the use of earplugs compulsory. It was a reminder that sometimes we don’t communicate well enough the advantages and benefits of mating a plastic sprocket to metal chain.
The most important advantage is less wear. When you mate metal to metal the abrasion will prematurely wear the chain and the sprocket’s teeth. Anytime you need to shut down for maintenance or replace parts costs your mill money! The reduced noise is the second benefit. Noise is a hazard and noise reduction should be a priority; however, while plastic-to-metal connections reduce noise, metal on metal increases it.
Many metal sprockets are also solid; however, Redco polyurethane sprockets have a detachable A-plate from the hub. This means when the sprocket’s teeth eventually do wear you only need to purchase new A-plates but not a full sprocket and this saves you money.
Lastly, polyurethane is an elastomer. This means it takes a measure of impact and then rebounds where metal will simply dent. Have you had impact issues affecting your metal sprockets? Polyurethane would make an ideal solution.
Redwood Plastics and Rubber offers a wide variety of split and solid polyurethane sprockets for 81X/H78 chain. Check them out here.
Our popular “Oregon Bends” are plastic chain channel we form into semicircles for when sawmill chain wraps around a bend. These are not a “standard” solution as the channel used, infeed and outfeed are different depending on the mill. To that end we’ve prepared a spec sheet that gives the customer everything they’d need to get a quote. You can download the drawing below, print it, fill it out and email it to Redwood Plastics and Rubber.
Redwood Plastics and Rubber offers two “pulp safe” plastics and while they might appear to be interchangeable or similar, they’re really not, and have both different properties and applications. In fact, it’s critically important to know where each should be used. SPS-2000 is meant to dissolve in the kraft mill chemical process and should be the only of the two plastics used in kraft mills! This is because Synsteel will not dissolve under the same process! Conversely, SPS-2000 is not suitable for pulp mills that do not use the kraft process. Those mills use metal detectors and that is where Synsteel, with its embedded metal component, must be used instead. The easiest way to think about it is to use SPS-2000 in kraft mills and Synsteel everywhere else. At this point lets break down the materials.
Besides being kraft mill safe, SPS-2000 offers some other excellent properties. It is the slickest polyurethane product we offer with the lowest coefficient of friction. Its fillers also provide high wear and abrasion resistance combined with both load and impact strength. It is able to bear 2500 PSI load in application. SPS-2000 is quite dimensionally stable and resists most oils, greases, and solvents.
Redco Synsteel has a specific gravity > 2 meaning it will sink (unlike virgin UHMW, which floats). Also, the metal filling makes it attracted to magnets and will trip metal detectors (though that depends on the size of the piece). We’d be happy to mail you a free piece of Synsteel offcut to trial in your mill, cut into various pieces, and see how it detects. The steel filling also provides other benefits such as twice the compressive strength of virgin UHMW, improved abrasion resistance and reduced thermal expansion. All UHMW can take a beating but Redco Synsteel especially with these properties. This makes it an especially good product to use on the log deck (of any mill, not just pulp mills).
For more information or a quotation on Redco Synsteel or SPS-2000, please contact us today.
“Seeing is believing” goes the old cliche and while we can talk about using plastics in sawmills, OSB, or planar mills, nothing beats seeing these solutions in action! Fortunately, Redwood Plastics and Rubber has created a short minute and a half video on YouTube showing a few of these applications in use.
One of our recent solutions has been replacing UHMW L-shaped channel for chain runs in OSB mills with Redwood Plastics and Rubber Redco 750 polyurethane. The issue is that the chain creates too much heat on the UHMW plastic warping it and causing it to bubble. Redco 750 bears more load and its properties appear to dissipate the heat better resulting in a solution to the problem.
These channels can be manufactured in virtually every desired profile, though a one-time set up fee would be required for a profile with new dimensions. Once the tooling is done, shipments can be made in the reasonable time frame of typically 3 weeks. The material is flexible, yet strong, and resilient to abrasion and wear as well as carrying up to 2500 PSI of load.
Our estimators and sales people at Redwood Plastics and Rubber often receive request for quotes on UHMW trimmer or roller lugs. The issue is that customers often think the lugs they are using are ‘standard’ when this is not the case. In fact, our inventory holds hundreds of part numbers for different trimmer/roller lugs of all different thicknesses, lengths, and profiles. Thus when a RFQ comes in we treat it as a new custom part. Yet, these lugs are so common that we wanted an easy way for customers to specify their requirements.
Below you will find a blank drawing for a trimmer/roller lug. Simply print it, measure your existing lugs, fill in the measurements and email your request to firstname.lastname@example.org
Please be sure to include the quantity of lugs you require!
We often write about specific plastic sawmill solutions and what benefits those offer in regards to sawmill/planarmill maintenance. However, sometimes it’s good to take a step back and look at the big picture of why we put industrial plastic in sawmills in the first place. It really comes down to a few primary problems that plastic solves: shock, noise, and wear.
First of all, shock. Sawmills are dynamic operations often involving large logs being transported around mechanically, processed, and with lumber that’s still quite heavy being further transferred. While these logs and lumber move they bang around different pieces of equipment. As this occurs month after month, hour after hour, they can damage sawmill equipment. Weak areas such as welds are very prone to shock and impact. Plastics such as Redco Deadplate or dissipater channel assist in protecting equipment by absorbing this shock and thus protecting valuable sawmill equipment.
Secondly, noise. All this dynamic movement, chains running, banging of lumber and logs, causes a lot of noise. Often governmental agencies have limits on the decibel level of noise that is permissible in a facility. Plastics when mated to metal components greatly reduce noise and thus can assist to reduce the noise in a facility to more acceptable levels.
Last but not least, wear. When components of similar materials are mated to each other this causes increased wear. Examples would be metal sprockets mated to metal chain, or chain running in a metal channel. Plastics provide a low friction, wear-resistant surface, that when mated with metals increases the lifespan of expensive equipment. The reduction in maintenance needs also reduces maintenance downtime and thus increases time in production.
For more information on the benefits that plastics offer sawmills and planarmills, please contact us today.
Polyurethane is one of the main plastics used for sawmill applications. Everything as diverse as kraftmill safe machined U-channel, to sprockets, Shark Fin lugs, and bearings. Softer urethane being used for Redco Deadplate or other shock and vibration dampening products. Most of the time for customers color isn’t important but sometimes a mill manager or maintenance supervisor might think it is. This could be for any reason from part identification to ensuring a part is high visibility for safety reasons. The good news is that the polyurethane sawmill parts offered on this site are available in custom colors, usually with no additional cost! This assumes its a standard colorant that is stocked by Redwood Plastics and Rubber.
The exception to the “no additional cost” is the bearing-grade urethane Redco 750 used also in sprockets. To be clear, this product IS available in custom colors too – but there will be a charge that is quoted on a case-by-case basis. The reason is a separate machine is used to make these products that requires cleaning and a new set up to change color from the standard red. It is important for you to know it CAN be done! The high visibility option mentioned previously in either orange or yellow has potential that shouldn’t be discounted. If you have any questions, please contact Redwood Plastics and Rubber.
Plastics are excellent bushing material that replace metal. In contract to metal, plastic bearings are self-lubricating, require less grease or maintenance, and last longer. Typically six different plastic materials could be used as these bushings and each will be described.
Called “Redco 750 XL” this is a lubrication impregnated polyurethane bearing material. It’s used where shock and vibration are special factors. It has the advantage of being able to be molded which means a low per-piece cost when purchased in bulk.
The most common bearing material in a sawmill, nylon takes high pressure (4000 PSI) and is available in solid and liquid lubrication impregnated versions. High temperature formulas are also available.