General Product Questions
Why do you offer three different wheel compounds? What’s the difference between them?
Automobiles employ a variety of different tires and suspension types to suit various different applications. You’d likely not see the same tires on a luxury sedan that you’d see on a dump truck. Like automobiles, ELSCO roller guides are available in a variety of different configurations built to suit different end user requirements. Offering three different wheel compounds is one way we ensure that ELSCO guides are capable of handling every elevator application.
In most passenger applications, a smooth, quiet ride is of paramount importance. ELSCO’s standard roller – our black neoprene – is engineered for excellent ride quality and silent operation, offering the comfort characteristics of a luxury sedan. A synthetic rubber, neoprene has unique compression characteristics that make it absorb shock, vibration, and noise more effectively than any polyurethane. ELSCO neoprene compounds have been specially engineered for maximum effectiveness in elevator applications, and display excellent “memory characteristics, meaning that they retain their round shape and resist flat spots even after sitting overnight. Most reasonably balanced cars with standard loading characteristics should use these black neoprene rollers.
Most freight elevators do not require such a plush ride. Instead, they require a roller guide that can operate reliably in spite of very heavy or unbalanced loads. In these applications, we recommend our equivalent of the full-size truck – ELSCO red polyurethane roller wheels. Our hardest compound, the red polyurethane resists even the most demanding duty loads. There is a trade-off: harder rollers are less forgiving and ride quality is compromised. Additionally, we have found that harder rollers do not provide the same noise and vibration insulation, meaning hard polyurethane rollers can mean noisier elevators. For this reason, we do not generally recommend our red rollers at speeds above 350 fpm (1,75m/s). Nonetheless, in installations where ride quality and noise are not concerns, but high loading characteristics are (e.g. heavy duty freight elevators, stage lifts, or automobile lifts), red polyurethane rollers may be the answer.
Some elevators demand both durability and ride comfort, in spite of high speeds and heavy or unbalanced loads. These demands are typical in many hospital cars, as well as in high-speed service cars in high-rise towers. Silent operation and ride comfort are necessary for the passengers who use these cars, and for building occupants in proximity to the hoistway. At the same time, these cars must also accept bulky, heavy, and unbalanced loads. In these cases, intermediate-hardness green polyurethane roller wheels offer an elegant compromise. While they forgo some of the ride quality and sonic insulation benefits of the black neoprene rollers, and they are not as rugged as the red polyurethane rollers, they balance these traits in a manner that is suitable for many passenger/freight elevators. Green polyurethane rollers are the Sport Utility Vehicle of the ELSCO line: comfortable enough for in-town driving, but suitable for more utilitarian purposes, too.
Specifying which of these rollers is right for your application requires a combination of knowledge and experience. Call an ELSCO guide specialist at 410.363.9020, or email to email@example.com, to determine which ELSCO compound is right for you.
What makes neoprene so special? Why not just go with quiet poly?
Neoprene is a synthetic rubber, and rubber has different basic operating characteristics than any polyurethane. Rubber compounds actually compress under loading, while most polyurethanes tend to deflect out of the way. This compression characteristic facilitates a damping effect critical to genuine shock absorption. Properly engineered neoprene thereby provides better ride quality than even the softest polyurethane compounds.
Neoprene also has sound-deadening characteristics that help isolate the elevator from the rails. That’s why sound isolating pads used in a variety of different industries are made from neoprene. Elevators are noise-prone systems, with plenty of moving, vibrating, oscillating components. Sheet metal cabins can amplify this noise, and long steel cables transmit the sound throughout the entire building through the elevator rails. By virtue of their neoprene roller wheels, ELSCO guides act as rolling sound isolation mounts between the elevator system and the rest of the building.
ELSCO neoprene is additionally compounded with special “memory characteristics that help it to remember its round shape, resisting the flat spots that result in bumpy rides in less carefully manufactured roller guides. Even if an elevator has remained idle in the hoistway overnight or over a long weekend, ELSCO roller wheels quickly spring back to their original round shape for a smooth, silent ride. ELSCO inspects to a rigorous anticompression memory specification to make sure all rollers leaving its factory demonstrate these special characteristics.
How do I know which ELSCO roller guide to use for my installation?
ELSCO roller guide recommendations are listed in the Guide Selector Charts section of our comprehensive catalog. Please refer to these charts to determine which roller guide is appropriate for your installation. The charts recommend roller guides based on the variables of elevator type, speed, and load capacity, constrained within the indicated platform sizes.
If your particular application falls outside of the guidelines displayed in our charts, of if your installation has any unusual characteristics, we urge you to discuss your selection with us directly. Please call an ELSCO guide specialist at 410.363.9020, or e-mail to firstname.lastname@example.org, to determine which ELSCO guide is right for you.
What are adjustable stops? Do I need them?
Most ELSCO roller guides and swivel sliding guide shoes are spring-loaded to enhance ride comfort. Spring loading allows the car or counterweight to float somewhat independently of the rails, making for a smooth ride even when rails are misaligned. This float also helps compensate for unbalanced loads that may be present in the cabin. However, in most applications, it is necessary to limit this float, lest the car or counterweight stray too far from the rails and clip hoistway obstructions, such as veins, door clutch rollers, etc. Adjustable stops allow elevator mechanics installing ELSCO guides to set a positive, adjustable limit to the amount of float the elevator can experience, tailored to the specifics of the elevator in question.
ELSCO recommends adjustable stops on all car roller guides. As such, they are standard equipment on all of our roller guides whose primary application is on the car. The Express-6, Express-3, Model A, and Model B roller guides are always delivered complete with adjustable stops.
Although most counterweights do not require the use of adjustable stops, they are advisable in situations where high speed, high rise, or poor rail installation may lead to greater-than-normal counterweight float. As such, adjustable stops are available as an option for all ELSCO swivel sliding guide shoes, as well as for the Model C roller guide.
Because it is intended as a low-speed, low-rise counterweight roller guide, and rarely recommended on the cabin except in very low capacity, low-speed applications, adjustable stops are not available for the Model D roller guide.
The Model E roller guide is not spring-loaded and therefore does not require adjustable stops.
All of our Swivel Sliding Guide Shoes are available with adjustable stops as an option.
What are cover guards? Do I need them?
Cover guards are optional sheet metal plates that protect roller guides from falling debris, dust, or the occasionally ill-placed work boot. Cover guards are typically used only on the top two roller guides of the car or counterweight. They also serve a safety function, shielding the potential pinch point between rollers and rail. For this reason,they are occasionally used on the bottom of the car or counterweight as well.
These cover guards are generally optional, although certain consultants or regional specifications may require them.
ELSCO cover guard kits come complete with all necessary mounting hardware. In some instances, field modifications may be necessary to retrofit cover guards to roller guides that were not originally ordered with them.
We often hear cover guards described by other names: cover plates, top caps, top hats, bonnets, or fins.
Do you have guide rail force interaction ratings for your roller guides?
We do have guide rail force ratings for ELSCO guides, but you will not find them published in our catalog. We are aware that guide rail reaction forces (sometimes referred to as “Max Roller Forces, “Fx/Fy or “FF1/FF2 loads) have become an increasingly popular tool in the specification of roller guides and sliding guide shoes. However, we have found little consistency in how these rail reaction forces are calculated and applied. We also find that using rail reaction forces alone to specify roller guides can be detrimental to elevator performance.
Using catastrophic load conditions (such as seismic event loads) alone to specify a roller guide ignores the everyday conditions under which the elevator will normally run. Furthermore, since most elevator codes today require emergency guide plates, most spring-loaded roller guides never absorb the full impact calculated in these ratings – the plates engage the rail before the roller guides bottom out. Other inconsistencies in the use of these ratings make them more considerably more ambiguous than the speed/capacity ratings we have used, with great success, for 50 years.
As a result, we do not openly publish any force ratings for our roller guides, although we are happy to discuss these individually with customers on a case-by-case basis.
My roller wheels are wearing out quickly. What’s happening?
When roller wheels wear out prematurely, excessively high adjustment pressures are typically to blame. Excessive wheel pressure causes extreme deflection of the roller’s tire material. Extreme tire deflection, in turn, causes heat buildup that can destroy the roller material or affect its chemical bond to the aluminum hub. Proper spring tensioning of roller guides and reasonable static balance are therefore critical to proper roller and tire wear.ELSCO roller wheels should always be adjusted between 25 and 50 lbs. (12- 23kg) of pressure per roller wheel. At this pressure, it should be possible to skid the wheel on the rail by hand using only moderate effort. The steps shown below are an example of the adjustment procedures found in the installation instructions that are packaged with every set of ELSCO guides. The example given is from the Model A roller guide; please consult your guide-specific cut sheets for specific model instructions.
In addition to the “skid by hand with moderate effort rule as shown in the installation instructions, there are other simple ways to determine if a roller has been over-tensioned against the rail. Once they have been in use, most rollers will show a characteristic witness mark around the perimeter of the tread that clearly illustrates the deflection of the roller. If this line shows more than 1/32″ to 1/16″ (0,8mm to 1,6mm) of deflection, it is likely the rollers have been adjusted too tightly.
It is also important to note that the depth of the witness mark does not have a strictly linear relationship with the pressure applied. Because of the geometric profile of the wheel, it takes significantly more than twice as much pressure to create a witness mark that is twice as deep.
There is a cut in my roller wheel. Why is this happening?
These cuts are almost always caused by misalignment of the face, or nose roller with the front face of the rail. Although it is less common, it is also possible for the rollers on the sides of the rail to be positioned too far out so that they, too, hang over the corner of the machined portion of the rail. The wheel pictured above was a face roller; the tread on the right side of this wheel hung over the right corner of the rail. The sharp corners of the rail cut the radial groove evident in the photo.
To avoid this scenario, it is important to install all roller guides so that all roller tread runs completely on the rail. Proper 90 degree alignment to the rail is also important. If you have verified that all these installation guidelines have been properly followed, and are still experiencing problems, you should not hesitate to call an ELSCO guide specialist at 410.363.9020, or e-mail us at email@example.com. We are always available to help troubleshoot technical issues.
Does ELSCO recommend any routine field maintenance for roller guides?
ELSCO roller guides are manufactured to be robust, reliable, and trouble-free over the course of many years of operation. As such, our guides require very little in the way of routine maintenance.
Model A, Model C, and Express-6 roller guides do require lubrication between the base and the wheel cluster assembly. This should be performed upon installation and approximately once per year thereafter. Any hard, generalpurpose grease may be used. Refer to individual installation instructions for more information. Other roller guide models do not require any field lubrication.
A quick visual inspection is always a good idea to ensure that roller guides remain in good condition and are properly aligned. Even if installed perfectly, building settling or other elevator adjustments can alter roller guide alignment. Such a visual inspection should be performed annually, and after any other major elevator component replacement or repair. Roller guides that have been installed outdoors or in other challenging environments should be checked more frequently to ensure that corrosion has not impacted moving parts.
Note that roller wheels should be the only wear item requiring replacement under normal circumstances. Other components, including springs, screw machine parts, and elastomeric bushings (in Express-3 roller guides) are intended as lifetime items that should not require replacement during the life of the roller guide assembly, though the occasional wheel stud or wheel stud lock washer may be replaced if corrosion is highly in evidence.
What are ELSCO’s delivery lead times?
We understand that elevator maintenance is not the kind of business that operates on a convenient schedule. As a result, we work very hard to offer some of the shortest manufacturing lead times in the elevator industry. And as an ISO 9001- certified firm, we measure our on-time delivery to ensure we meet our stated lead times. Experienced industry professionals turn to ELSCO for fast, reliable turnaround of roller guides, parts, and accessories.
Telephone orders for replacement parts and roller wheels placed before 12:00pm (noon) United States Eastern Time are generally shipped on the same business day. Replacement parts orders received after noon are generally shipped the next business day.
Complete roller guide and swivel sliding guide shoe orders are built and packaged to order, although we always have parts and subassemblies in stock for optimal turnaround. Most small orders for roller guides (1-5 sets of guides) are shipped within 1-3 business days. Larger orders (6-20 sets) may take 5-8 business days. Extremely large orders may take several weeks, but we are generally able to make partial deliveries to keep crews busy and jobs moving efficiently.
We are also known for our ability to turn special rush requests very quickly, often bettering the general guidelines provided above. Call your rush order in to an ELSCO guide specialist at 410.363.9020 or e-mail to firstname.lastname@example.org to discuss the parameters of your urgent request.
I bought the wrong roller guides. Can I return the ones I have for credit?
ELSCO accepts returns of new, unused roller guides within six months of their original date of shipment to the customer for a 15% re-stocking fee. The customer remains responsible for freight costs in both directions. Customers wishing to make returns should call ELSCO at 410.363.9020 or e-mail to email@example.com to receive a Returned Materials Authorization number that will facilitate the issuance of return credit.
We are very sorry not to be able to accept returns on roller guides once they have been bolted on to the elevator, or after they are more than six months old. We charge a small re-stocking fee in order to recoup some of the overhead costs associated with filling an order, but the remainder of the value we refund depends on the enduring salability of the returned products. Because we can no longer guarantee the quality of a roller guide once it has been installed, or once it has sat in storage outside of our control for longer than six months, we are not willing to pass the goods along to another customer.
In the rare event that you have received incorrect items as a result of an ELSCO error, please do not hesitate to call us at 410.363.9020 or e-mail at firstname.lastname@example.org. As an ISO 9001- certified firm, we strive for total customer satisfaction. Should we make an error, we welcome the opportunity to make things right.
Why do you sell your guides in sets of four? Do I have to buy a complete set?
Because a typical elevator car or counterweight requires four roller guides or sliding guide shoes, our standard unit of measure for all of our complete roller guide assemblies is the set of four.
We also sell our adjustable stop kits and seismic retainer plates in sets of four. You do not have to order a complete set of four. We are happy to break our sets down into half-sets or quarter-sets as needed.
Please note that some of our accessories and replacement parts are still sold individually. In particular, it is important to remember that our cover guard kits are sold per each. Because cover guards are generally only used on top roller guides, two cover guards are typically ordered for each set of four roller guides.