Tech Talk Blog

Did you realize there are probably over 300 types of Rulon? Rulon is a self-lubricating material that can almost be considered “generic” in some ways.  It is a PTFE material with various fillers; it is the type and amount of filler that makes each variation of Rulon unique.

When choosing Rulon, we ask:

1) What is the application function – bearing? Seal? Gasket? Some materials can be used for all applications.

2)  What is the temperature? -400 to +550 is the general range Rulon can accept. For design purposes, we need to know how much press fit and close in to account for in the gradient.

3)  What is the environment? Some types are made for FDA or USDA environments or for resisting abrasion. Most PTFE materials don’t do well in water, but a few do.

4)  What is the speed? All types of Rulon can take 400/500 feet per minute without lubrication; but we need the load to be a bit more accurate. Rotating? Oscillating? Linear?

5)  What are the loads on that bearing? Most can handle 1000 psi, but others can withstand higher levels.

6)  What type of hardware (consider temperature)? Only a few types of Rulon can work with stainless steel.

7)  What is the surface finish? 8-16 rms on the shaft is recommended, but for holding purposes, we would suggest 32 rms.

We can help you choose the right Rulon for your application.

We see this question often.  Plane bearings offer many advantages; a simple design, self-lubrication, a wide range of operating parameters, and lower cost.

When selecting a plane bearing, consider:

Load – this can be the most difficult attribute to define. What is the pressure? Multiply the ID times the length, and then divide the load by that number. Pressure (P) is expressed in PSI.

Speed – you may know what your shaft speed is, but you need to find the velocity (v). Take the diameter multiplied by pi, then multiply by the RPM. Divide this number by 12, because V is measured in surface feet per minute (SFPM). Every material is rated for a maximum velocity.

P and V – these must always be considered in tandem. The combination of load and speed generates frictional heat. Always review P x V or PV. Every material has a maximum PV rating.

Material Rating – look at all the values for each individual project. Plastics are insulated in nature, and heat will kill a plastic bearing faster than anything else.  Be sure to stay within the known limits to understand what materials are capable of taking.

Temperature – this is critical to getting the proper “press fit”.  Be certain there is no loss of tolerance or close-ins.

You can also visit our Plane Bearing Design Worksheet for guidance, or contact us directly.

Plane bearings are straightforward; two surfaces moving against each other without the aid of a rolling element. A shaft turning in a bushing, a slide pad damping vibration, a bridge joint expanding, and a chain running through a channel are all examples of plane bearings. Sleeve or flange bushings, thrust washers, linear-slide plates, friction bearings, and wear pads all fall into the plane-bearing category. If there are no balls, needles, retainers, or races, it’s a plane bearing.

Plane bearings stand up to most industrial and outdoor applications. They are self-lubricating and offer superior resistance to fresh water, saltwater, deionized water, slurries, acids, or bases. And because they have few moving parts, most plane bearings are not adversely affected by particulates like coal dust, quartz debris, sand, and road ballast. Plane bearings are safe for clean rooms, too, because they produce minimal debris and won’t attract dirt. Many materials also meet FDA, USDA, 3A, or NSF standards.

Our team can walk you through our complete selection to make sure you get the right fit for your application.

Ultracomp Composite Bearings are designed for extreme loads where impact and vibration may occur. Because of it’s very high impact strength it can take extreme loads as well as shock loads. Ultracomp requires no lubrication which eliminates maintenance, is much kinder to the environment and reduces overall costs of ownership.  Ultracomp absorbs virtually no moisture, takes static loads up to 55,000 psi and handles dirty, gritty environments. Ultracomp is also an excellent underwater bearing for applications as diverse as bowthrusters, rudder bearings, roller bearings, dockside equipment exposed to salt air and water. Also an excellent bearing material for construction, material handling and ag equipment.

Visit our Video Learning Center to learn more about all we have to offer.

Rulon bearing materials, and other filled PTFE materials like Fluorosint and Ultraflon, have a unique reaction where coefficient of friction is concerned. Unlike most materials which theorize that higher loads and speeds mean higher friction, filled PTFE products are just the opposite. WIth these materials, the higher the load – the lower the friction. Same goes for speed as a general rule. Design your PTFE bearings with the thought in mind that surface contact area can be reduced dramatically to optimize friction properties. Remember, more is not necessarily better when it comes to PTFE based bearing materials.

Still have questions? Don’t hesitate! Ask The Experts!