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 email@example.com
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.
While many maintenance managers know about UHMW U-channel for use with sawmill chain, less people seem to know that the same yellow/clean/reprocessed material that provides the channel with its excellent benefits is also available in simple, flat, wear strip. This typically comes in 250′ coils though it can be purchased in cut-to-size strips that cost approximately 50% more per linear foot than the full coil. The most common thickness of this stock is 3/8″; however, customers also request 1/4″ and 1/2″ thick strips at times. Widths up to 6″ are available. This is an excellent solution to bolt in on top of existing metal channel. The product is slick, long-lasting, and increases profit by increasing the lifespan of the mated chain (so it lasts longer) as well.
Swapping out customer’s existing metal sorter sheaves for our nylon sheaves is a typical sawmill application for industrial plastic. But why should you consider this investment? The answer comes down to the fundamental properties of nylon and the benefits it offers to your mill. Unlike most metals, nylon sorter sheaves will not rust and they are also lighter and easier to install. They are commonly available in a dark grey “moly-filled” version of nylon plastic called Redco MD but can also be had in oil-filled grades permitting less lubrication. Redco MD’s moly filler provides excellent wear properties on lower rotation applications. The plastic is long-lasting and requires less maintenance. While a press fit bearing can be supplied, the material itself is also a fantastic bearing material so a simple thru-hole for the bore is usually the most economical.
Polyurethane J-hooks and C-bars are a sawmill staple, with the plastic used usually being 75D hardness polyurethane. These hooks and c-bars are typically molded which means there is an upfront tooling cost; however, the per-part price is much lower than a machined part. Redwood Plastics and Rubber can manufacture whatever hook profile you need but there are other modifications to these hooks that can be done to suit customer’s needs. Firstly, a grit surface can be provided which increases the grip characteristics of the hook. LSI (steel later plates) are commonly embedded in the slider block at the top where the hook gets bolted in to provide reinforcement. In addition, the hooks can be manufactured out of SPS2000 which is kraftmill safe.
The colors of the hooks can also be customized (does not cost additional unless it’s a non-standard colour). Other potential additions include adding a screw for metal detectable properties or embedded lubricants.