Still need holiday gift ideas? How about one from Gates!

Are you still looking for those last minute holiday gift ideas?  Here is a great one.  REI has recently started selling a bike from their Novara line called the Arkham.  This belt drive beauty won't fit in your stocking, but would look just right underneath the Christmas tree.  Equipped with a Gates Carbon Drive belt, and a SRAM 3 speed hub, this thing would make anyone a happy commuter.  Check it out here:

http://www.rei.com/product/857591/novara-arkham-bike-2014

BladeRunner Belts

A lot of people call us looking for specialty length BladeRunner Belts.  Unfortunately this is not usually an option.  BladeRunner are OEM specific belts, and usually made to special lengths, or even special constructions that cannot be replaced with other off the shelf belt lines.  This is also why the part number is not a description of the belt's dimensions.  The best potential option for replacement of non-standard size BladeRunner belts are our PoweRated line of belts.  However, these belts are typically only offered in inch increments, and not in as long of options as some of the BladeRunner series.  Knowing this issue may help if you are trying to redesign any part of your lawn and garden, or low power requirement equipment.

EZ Align Service

Do you have a Gates EZ Align laser alignment tool in need of repair?  If so, we have someone for you to talk to.  Contact Bill Seiffert at Seiffert Industrial for assistance:

Bill Seiffert
Seiffert Industrial
972-671-9465 x 102

HVAC Equipment Inspection

Many air handling drives have structures that are not particularly rigid, which can create belt tension and drive alignment problems resulting in unusual and premature belt wear. Synchronous belts are sensitive to fluctuations in center distance that can be caused by inadequate bracketry. Under start up conditions, an AC motor can be required to provide 150% to 200% of its rated capacity. Synchronous belts cannot slip, and must transmit the higher start-up torque. Under these conditions, the drive center distance may collapse if the

structure is not sufficiently rigid.  With the drive shut off and safely locked out, a simple method to use when

inspecting potential drive conversions is to grab the two belt spans and push them together while observing the motor. If any significant relative change in center distance or motor position is noticed, the drive’s structural strength is most likely insufficient for a simple conversion. The structure would need to be

reinforced to obtain optimum performance from a synchronous belt drive. The best conversion candidates have motors that are mounted solidly on support bracketry that is part of the fan’s structural system. When possible, select synchronous drives with diameters similar to existing V-belt sheave diameters. This will maintain similar belt pulls and loads on the shafts and structure.

Frequency and Tension

Occasionally we get asked about how to calculate tension based on the Sonic Tension Meter frequency measurement.  The STM will calculate tension in pounds or Newtons for you with the proper input, but the math behind it is really pretty simple.  Here's how to do it by hand:

Formula:

T = 4 x M x W x S^2 x f^2 x 10^-9

Where:

T = Belt span tension
M = Belt mass constant
W = Belt width or number of strands
S = Length of the span to be measured
f = Natural frequency of the belt

Make sure to use proper units!

Gates North America Engineering Support

We are often contacted by Gates customers all over the world, yet there is very little support we can provide to customers outside of North America. Gates product lines vary throughout the world. Technical information from Engineers in North America will not apply to the products available in other regions. For assistance in your area please go to www.Gates.com and select your region using the map in the top left of the screen. You may also use these contacts:

Europe:                 pteusupport@gates.com
Australia:               gatestech@gates.com
Asia Pacific:          guatc@gates.com
India:                      customercare@gatesind.com
South America:     br.ind@gates.com
Inter America:       gatesinteramerica@gates.com

Taper-Lock Type Sprocket Installation and Removal

Taper-Lock Bushings attach a sprocket to a shaft.  They are for the most part industry standard, but when people see them for the first time, many times they are confused about how to install them.  Luckily, our Drive Design Manuals (such as our Poly Chain GT Carbon Drive Design Manual) have a step by step process listed for easy installation and removal of these bushings.  You can find the specific page below, or download the entire manual here: http://www.gates.com/catalogs/index.cfm?requesting=ptcatalog&location_id=2999 

Speed Limit Evaluations For Belt Drive Hardware

Rotational speed limitations for belt drive hardware is based on material composition and balancing standards.  The traditional industry accepted speed limitations for gray cast iron material and static balancing is 6500 ft/min.  For speeds higher than this, materials such as ductile iron, steel and aluminum may be considered, but are typically available on a made-to-order basis at higher cost.  Dynamic balancing is also recommended for operating speeds above the 6500 ft/min limit to prevent excessive vibrations.

In more recent years, the Mechanical Power Transmission Association (MPTA) published the MPTA-B2C - Standard Practice For Sheave/Pulley Balancing Standard based on International Standards Organization (ISO) and American Gear Manufacturing Association (AGMA) balancing standards.  This MPTA standard provides a more accurate and objective evaluation of whether static or dynamic balancing is required. 

The MPTA-B2C balancing standard includes a simple maximum static balancing speed calculation based on diameter and face width.  When operating speeds are not known, static and dynamic balancing recommendations are also provided based on material and hardware weight.

Gates Design Flex Pro drive selection software utilizes the MPTA-B2C balancing calculation.  This may prevent the selection of some drive combinations that would otherwise operate below the traditional 6500 ft/min limit for gray cast iron and static balancing.  Warning notes indicating a need for dynamic balancing at operating speeds below 6500 ft/min may also appear due to this.

In summary, while the traditional industry accepted 6500 ft/min limit for gray cast iron materials and static balancing is a reasonable guide, the MPTA-B2C balancing standard provides a more accurate and objective evaluation of the need for dynamic balancing based on diameter and width.  This calculation is utilized in Gates Design Flex Pro software and may limit drive selections that would otherwise appear to be acceptable.

For questions or additional information, feel free to contact Product Application Engineering at (303) 744-5800 or ptpasupport@gates.com.

Minimum Pulley Diameters: How small is too small

As technology advances and systems get smaller and smaller so too does the desire for smaller drive pulleys.  Though size can be decreased, it is important to ensure that none of the drive pulleys fall below the minimum recommended diameters given this can result in shortened belt life, premature belt wear, and overall poor drive performance. Below are the minimum pulley sizes for both V-belt sheaves and Synchronous sprockets.

It is still important however to check with the motor or gearbox manufacturers to ensure that these small pulley sizes do not result in excessive shaft load or fall below any NEMA (National Electric Motor Association) standards which could prove to be detrimental to the drive components. For any additional questions feel free to contact us at ptpasupport@gates.com or 303-744-5800.

Got Questions? Gates Experts Are Ready to Help

The complex demands of today’s operations present significant challenges. Preventing downtime, ensuring performance, and controlling costs often require deep expertise in highly technical areas. You can rely on Gates engineers to help you deal with these issues. Thorough training combined with ongoing, real-world experience gives them a unique ability to analyze your situation and offer solutions that meet your needs. They know the technology inside out. They understand the requirements of your enterprise. And each one is completely invested in your success. To connect with a Gates engineer, please leave a comment. We’ll be glad to reach out to you.

Belt Working Tension Ratings

For long length or linear applications the maximum dynamic drive tension should be compared to the belt’s allowable working tensions for proper belt width selection, rather than the ultimate tensile, or breaking, strength. Working tension ratings are based on the HP ratings for our belts. We simply convert the HP rating to a torque rating at a given speed, and then divide by the sprocket’s radius. It is much better to base drive designs on the prime mover output ratings instead, as this better represents the amount of energy that can potentially be applied to the system. We recommend basing your design on our published HP rating tables or design software, and using an appropriate service factor.

Each driven and driver sprocket should have 60 degrees of wrap and 6 teeth in mesh. 20% of the HP rating will be lost for each tooth less than six not in full contact. For example, if only 5 teeth are in mesh around a driver or driven sprocket the HP rating will be 80% of what’s shown in the attached tables.

John Force Wins 2013 NHRA Funny Car Championship with Gates as Sponsor

John Force won his fourth race of the 2013 season and his record 16th World Championship on October 27 at the NHRA Toyota Nationals at The Strip at Las Vegas Motor Speedway. John Force faced his daughter Courtney in the final round, with a winning 4.062 second ET at 310.63 MPH run to defeat Courtney's 4.085 second ET at 319.22 MPH. On his way to the race win and points championship, Force had a wild semi final run, needing repeated "pedaling" to attempt to hook the car up and stop the tires from breaking loose. Pedalling is very harsh on the blower belt drives, with repeated tension reversals and shock loads, but the Gates Poly Chain belt held on to get Force down the track to win the semi final run and set him up for his historic 16th Funny Car championship. Just one more testimonial of the toughest, baddest belt on the planet - Poly Chain GT Carbon.

Set Screw Torque Values

Working on my vehicle the other night, I broke a tool from applying too much torque. I should have been using my torque wrench - I know this. Torque values are important. Using the correct torque values when installing set screws does two things: first, it guarentees that you have applied enough torque to keep the set screw from slipping, which could be a safety issue, and second, it keeps damage from occuring to the set screw, the sprocket, and the shaft. Refer to the chart below to find the correct set screw torque for your application.

Wind-Milling and Gates Draftguard

Large air moving fans used in air cooled heat exchangers or cooling towers sometimes “wind-mill” while powered off.  Wind-milling occurs when back drafts cause fans to rotate backwards when out of service.  This can present safety concerns to personnel working in the proximity of the fans.  It can also damage fan structures and belt drive systems when the units are powered on and the counter-rotating fan inertia energy is quickly dissipated and absorbed by the structure and power transmission system.

The Gates Draftguard product eliminates these issues.  It consists of a strong one-way clutch that mounts directly to QD bushing sizes E, F and J and TaperLock bushing sizes 3020, 3525, 3535 and 4030 or directly to fan shafts.  With Draftguard mounted and the torque arm secured, fans can no longer counter-rotate, but are free to rotate normally when powered on.  This eliminates system start-up shock loads and enables technicians to perform maintenance operations on belt drive systems without concern of unexpected backwards movement.

Draftguard is a great product to consider when drive shaft counter-rotation causes safety concerns.  Draftguard also reduces the chance of structural damage and synchronous belt tooth jumping when high inertia and counter-rotating fans are started.

For more information, contact Gates Product Application Engineering at 303-744-4947 or ptpasupport@gates.com.

How Much Center Distance Adjustment Do YOU Need For Your V-Belt Drive?

When designing a new belt drive system it is important to ensure that adequate installation and take-up adjustment is provided to allow the belt(s) to be both properly installed and tensioned throughout the life of the drive.  This is a commonly overlooked consideration due largely to poor installation and maintenance practices.  These practices include rolling belts on when there is insufficient installation adjustment or lack of a preventative maintenance schedule to ensure proper tension is maintained.  Properly installing and maintaining the drive will not only result in increased belt life and performance, but will also increase the overall efficiency of the drive when properly tensioned.  A quick reference to the charts below will help to ensure that the minimum center distance allowances for belt installation and take-up are achieved.  

For any additional questions feel free to contact us at ptpasupport@gates.com or 303-744-5800.

Gates Sponsored NHRA Team Update

The NHRA season is racing to its conclusion, with 4 races left in the 2013 Countdown to the Championship. Gates is proud to sponsor John Force Racing and Don Schumacher Racing. Gates Poly Chain belts are used in the Top Fuel and Funny Car classes to drive the supercharger. The supercharger application is harsh and demanding, with high speeds, extreme HP requirements, and severe torque reversals. The Poly Chain belt is the only belt that can handle the highly destructive application. With only 4 races left, culminating in the final race on November 7-10 in Pomona, CA, the Gates sponsored cars and their teams are shaking out in their chase for the 2013 season championship. Top Fuel Spencer Massey (Don Schumacher Racing) Currently 1st Place Tony Schumacher (Don Schumacher Racing) Currently 5th Place Anton Brown (Don Schumacher Racing) Currently 8th Place Funny Car Matt Hagan (Don Schumacher Racing) Currently 1st Place Robert Hight (John Force Racing) Currently 3rd Place John Force (John Force Racing) Currently 4th Place Jack Beckman (Don Schumacher Racing) Currently 5th Place Ron Capps (Don Schumacher Racing) Currently 6th Place Johnny Gray (Don Schumacher Racing) Currently 7th Place Courtney Force (John Force Racing) Currently 8th Place

Belts and Hose in Different Zip Codes

Gates Corporation is the industry leader for belt and hose products, and its distributors are located all over the world. It's easy for North American customers to locate a distributor near them by clicking the "Where to Buy" tab anywhere on the Gates website or by simply using this link Distributor Locator.

PowerGrip GT2 – The Best Fit for Your Positioning Drive

PowerGrip GT2 belts are an advanced design of Gates HTD system and feature:

• A higher load-carrying capacity and longer belt life than either the PowerGrip HTD or PowerGrip Timing belts.
• The greatest registration and indexing accuracy.
• A modified curvilinear tooth profile with mating sprocket grooves.

This deep tooth profile of the PowerGrip GT2 belts provides…

• Increased contact area and improved resistance to ratcheting.
• Easy, clean entering and exiting the sprocket groove resulting in reduced vibration.
• Parallel contact with the groove eliminating stress concentrations and tooth deformation under load.
• Improved registration characteristics and maintains high torque carrying capability up to 2X that of PowerGrip HTD belts and 3X that of PowerGrip Timing belts.

As a comparison, the PowerGrip GT2 belts greater tooth depth and increased contact area results in full flank contact whereas the PowerGrip Timing belt primarily contacts the sprocket in the root radius only.  In addition, though the PowerGrip HTD belt has a deep tooth profile, it has considerably greater backlash due to the relatively poor belt/sprocket pitch fit when compared to the PowerGrip GT2 belt (see illustrations below).  

Wet Evaporative Type Air Cooled Heat Exchangers

V-belt drives in wet evaporative type air cooled heat exchangers are sometimes converted to synchronous belt drives for more constant fan speed, reduced maintenance and to reduce energy consumption.  While these benefits are often realized from belt drive conversions in many industrial systems, this particular application can be especially challenging.

Wet evaporative air cooled heat exchangers are sometimes structurally compliant allowing drive center distances to flex while in operation.  This allows belts to loosen dynamically resulting in accelerated belt tooth and sprocket groove wear.  Moisture seems to accelerate the rate of wear further with Poly Chain GT Carbon belts.   The first Poly Chain GT Carbon belt may last up to 6 months or so, then 2 to 3 months for the second and then maybe a couple of weeks for the third.  Belt teeth typically wear to a sharp point resembling “shark fins”.  By this time the sprocket grooves are often worn severely as well.

Poly Chain GT Carbon drive system life can be extended up to 12 to 15 months in these adverse applications with nickel plating on the sprocket groove surfaces.  Nickel plating is best applied to fresh cleanly machined sprockets as opposed to sprockets that have been painted or coated previously and then stripped.  In addition, sprocket finish diameters for freshly machined sprockets are corrected to account for the added thickness of nickel plating.  This improves the belt meshing quality reducing component wear.  Our Made-To-Order Metals Group can assist with properly plated sprockets that will perform well.  Contact them at makemymetal@gates.com or at 800-709-6001.

A quick and easy test for structural compliance is to stop the drive system, safely lock it out and then pull or push the belt spans together.  If any shaft or structural movement can be detected, the structure is not adequately sound for synchronous belt drive systems. In these cases V-belt drive systems are probably the better choice.

For further information feel free to contact us at ptpasupport@gates.com or at 303-744-5800. 

Synchronous Belt Drives in Wet Environments

Light and occasional contact with water (occasional wash downs) should not seriously affect synchronous belts. Prolonged contact (constant spray or submersion) results in significantly reduced tensile strength in fiberglass belts, and potential length variation in aramid belts. Prolonged contact with water also causes rubber compounds to swell, although less than with oil contact. Internal belt adhesion systems are also gradually broken down with the presence of water. Additives to water such as lubricants, chlorine, anti corrosives, etc. can have a more detrimental effect on the belts than pure water. Urethane timing belts also suffer from water contamination. Polyester tensile cord shrinks significantly and experiences loss of tensile strength in the presence of water. Aramid tensile cord maintains its strength fairly well, but experiences
length variation. Urethane swells more than neoprene in the presence of water. This swelling can increase belt tension significantly causing belt and related hardware problems.

Fiberglass vs. Aramid Tensile Members In Belts

Inquiries about belts manufactured with aramid tensile members are fairly common. Aramid fibers are known for their high strength and low stretch properties. DuPont’s registered trade name for their aramid fiber is Kevlar®. Both V-belts and synchronous belts can be manufactured with aramid tensile members and have definite benefits as well as drawbacks.

V-belts with Aramid Tensile Cord
Aramid tensile members provide greater tensile capacity and robustness to V-belts. V-belts utilizing aramid tensile members generally utilize premium materials throughout and can carry greater loads than standard belts with polyester tensile members. High tensile strength translates into higher working tensions. High tensile modulus (low stretch) is also beneficial in keeping belt elongation over time low. The Gates Predator® V-belt line is an example of ultra-high performance V-belts with aramid tensile members.

Material costs for aramid V-belts are greater than for standard V-belt constructions. Reduced belt elongation helps keep drive center distance adjustment ranges low, but belt tension levels drop more rapidly with the reduced elongation than with standard belts. In the end, belt re-tensioning intervals for aramid type V-belts and standard V-belts are the same.

Synchronous Belts with Aramid Tensile Cord
Aramid tensile members provide rubber synchronous belts with exceptional shock and impulse load resistance. Fiberglass tensile members used in standard rubber synchronous belts tend to break down when shock loaded as individual glass filaments buckle and fracture. Even though somewhat stronger, however, synchronous belts manufactured with aramid tensile members are not rated for higher working tensions because the load capacities of other belt components remain the same. Even though aramid tensile members may be capable of higher working tension levels, belt teeth limit overall belt load capacity as they become the weaker link.

The length instability of aramid tensile members creates challenges in belt manufacturing processes and in actual belt drive applications. Aramid materials change length as they absorb and release moisture. Changing humidity influences belt manufacturing length targets as well as how belt teeth mesh with sprockets in actual belt drive applications. In addition, aramid tensile members have a negative thermal coefficient causing them to expand and contract opposite that of metal. As machinery warms up in usage and structures expand, aramid belts shrink and become tighter. Aramid belts also loose tension rapidly with structural contraction during cooling as they lengthen. In addition to belt length and tension challenges, material costs for aramid synchronous belts are greater than for standard belt constructions and aramid synchronous belts are all manufactured on a made-to-order basis in minimum order quantities.

Summary
Aramid tensile members are beneficial in increasing the load capacity and performance of V-belts and in improving the resistance of synchronous belts to shock and impulse loading. These benefits come along with belt length instability issues that must be considered when making belt selections. The potential drawbacks of aramid tensile members may not be realized in some applications while they may create serious performance challenges in others.

Online Catalog and Drive Design Manuals

Have you looked at your current copy of the Gates Power Transmission Products Catalog recently?  If you have and noticed that your Catalog doesn’t look like the image below then you are potentially missing changes and updates that may affect your ability to select the best, most up to date product for the specific application in question. 



Gates 2012 Power Transmission Products Catalog



If keeping the latest version of the Catalog on the shelf becomes daunting, then it is important to note that the most current Catalog is also available for download from our Gates Catalog Page online (click link to be taken to Catalog Page).  In addition to downloading the entire Catalog, individual Catalog sections can be downloaded in the event only a specific product type or category is needed.  If you have the most current version of the Catalog on hand but need information from one of our Drive Design Manuals, these too can be downloaded in PDF form from the Gates Catalog Page. 

Finally, this Catalog page also contains PDF documents regarding belt interchange, belt identification, the Sonic Tension Meter manual and Preventative Maintenance manual.   Overall, having the ability to navigate to the Gates Catalog Page is a great reference tool to build on your knowledge of Gates products and design support.

Design Flex® Mobile

Gates is proud to introduce another resource for designing belt drives and/or calculating installation tension. You may be familiar with Design Flex Pro or Design Flex Web, but now Design Flex Mobile is available. Design Flex Mobile bridges the gap between our web based software and phone app, PT Toolkit. Unlike Design Flex Web, this mobile version can be accessed on ANY device connected to the internet. This puts the power of Design Flex in the palm of your hand, without having to download the PT Toolkit app.

507C Sonic Tension Meter Warranty and Repairs

The Gates 507C Sonic Tension Meter is an excellent tool for measuring belt installation tension accurately by reading the frequency of vibrating belt spans.  It is widely used in industry and is considered to be one of the finest belt tension measuring tools available. Gates provides full support for 507C meters including troubleshooting, accuracy certifications and repairs when needed.

Gates 507C Sonic Tension Meters are warranted for 2 years (sensors not included). No-charge repairs are available for meters within the warranty period. Repairs are also available for meters outside of the warranty period. Meters are evaluated in house and repair estimates are provided before work is completed.

New meters are not factory certified for accuracy, but traceable accuracy certifications are available as needed for ISO quality requirements. Certified meters are returned with a sticker and certificate verifying accuracy and the date of inspection. Note that certifications are not included in the meter warranty.

Meter repairs and certifications must be initiated through authorized Gates industrial distributors. Meters cannot be returned to Gates directly. Your local distributor is familiar with the returning process and will be happy to provide assistance. They will provide quotations for repairs or certifications and handle the paperwork and shipping. Go to http://www.gates.com/industrial/distributors  to use our distributor locator tool.

For assistance with 507C Sonic Tension Meters or any additional questions feel free to contact us at ptpasupport@gates.com or 303-744-5800.

Calculating Synchronous Belt Speed

For linear belt applications, it is often desirable to determine belt speed. The speed depends on both the sprocket pitch diameter and rpm.  It is calculated as follows:

S = (pd x rpm)/3.82

     Where:
      S  is the belt speed in feet/minute
      pd is the sprocket pitch diameter in inches
      rpm is the sprocket speed

Correctly Using a String or Straightedge to Measure Misalignment

Outside of the Gates EZ Align Precision laser Tool, a straightedge and/or a string are commonly used to measure and monitor misalignment in belt drive systems.  Unfortunately, these tools are commonly misused which can result in inaccurate conclusions about the actual drive alignment. 

A straightedge, such as a large ruler or other precision machined edge, should be used to project the orientation of one pulley face with respect to the other.  In other words, the straight edge should be contacting the reference pulley across the entire face of the pulley and be contacting both edges.  This straight edge projection should then be compared to the secondary pulley to determine the severity of the misalignment. 

When utilizing a string to gauge misalignment it is important to ensure that the string is held taught and is contacting the pulley at both edges of the pulley face.  The string then needs to be kept as straight as possible to ensure the most accurate alignment conclusion can be made. 

It is important to verify that the edges of both pulleys are of equal thickness, especially with V-belt sheaves, given if the edges are of different thicknesses the actual riding surfaces of the belt can be misaligned regardless of the edges being aligned.  Therefore, if the edge thicknesses are different, it is necessary to quantify this difference and ensure the pulleys are offset to account for this thickness variation.  Though this method is relatively simple, it can easy be misused and result in misaligned drives with decreased life, performance, and stability. For any additional questions feel free to contact us at ptpasupport@gates.com or 303-744-5800.

When In Doubt....

F = MA Actually, a simple formula that is quite often forgotten or overlooked by designers. The key point to remember is that the appropriate sizing of your belt drive is only as good as the load calculation or estimation used to design it. F = MA

Use of Flanged Sprockets

Guide flanges are needed in order to keep the belt on the sprocket. Due to tracking characteristics, even on the best aligned drives, belts will ride off the edge of the sprockets. Flanges will prevent this belt ride-off. On all drives using stock or made-to-order sprockets, the following conditions should be considered when selecting flanged sprockets:

1. On all two-sprocket drives, the minimum flanging requirements are two flanges on one sprocket or one flange on each sprocket on opposite sides.

2. On drives where the center distance is more than eight times the diameter of the small sprocket, both sprockets should be flanged on both sides.

3. On vertical shaft drives, one sprocket should be flanged on both sides, and all the other sprockets in the system should be flanged on the bottom side only.

4. On drives with more than two sprockets, the minimum flanging requirements are two flanges on every other sprocket or one flange on every sprocket —on alternating sides around the system.

On made-to-order sprockets, flanges must be securely fastened, such as using mechanical fasteners, welding, shrink-fit or other equivalent methods.

Adjustable Motor Mounting Bases

There are many components used in belt power transmission systems that are critical, but some may not be as readily apparent as others. An example is electric motor mounting bases.

While motors can be bolted directly to structures by their mounting feet, this does not always allow for necessary movement and adjustability. Adjustable motor bases are commonly used to secure motors while providing a means of positional adjustment. While types, designs, and methods of adjustment vary with brands and size, the best designs adjust with large linear screws.

Focusing on belt drive systems, adjustable motor bases are used to shift motor positions for belt removal and for new belt installation. They are also used to shift motor positions for belt pre-tensioning. Another critical function of adjustable motor bases is adjusting and maintaining motor shaft position for alignment with driven shafts. Accurate shaft alignment is very important for good belt performance, especially with synchronous belt drive systems.

Figure 1 – Single Screw Adjustable Motor Base

Figure 1 illustrates an adjustable motor base utilizing a single adjustment screw. While screw adjustment is superior to bases that only slide, side forces exerted by belt drives on motor shafts generate torsional forces. Single screw adjustment bases often deflect resulting in non-parallelism between motors and driven components. Correction with single screw designs can only be accomplished by applying external forces to motors and bases, which becomes difficult with increasing motor size. Single screw adjusting bases are used mainly for their economics, but do not generally maintain adequate shaft alignment nor belt tension.

Figure 2 – Duel Screw Adjustable Motor Base

Figure 2 illustrates an adjustable motor base utilizing duel adjustment screws. While motor bases of this type generally have fairly heavy duty designs, small torsional deflections can be compensated for fairly easily while applying pre-tension to belts. Adjustments to shaft alignment and belt tension levels are easy and accurate with this type of motor base design.

The design and condition of adjustable motor bases can have a critical effect on belt drive service and performance. When performing maintenance operations, replacing belts or converting V-belt drives to synchronous drives, consider upgrading inferior and insufficient motor bases to heavy duty duel adjusting screw types.

Underwriters Laboratories (UL) Certification for Industrial Belts

When UL certification is desired for a product that includes a belt drive, it is typically applied for by an original equipment manufacturer for their finished product (e.g. air conditioner, compressor, lawn mower, vacuum cleaner etc.) rather than at the component level (e.g. v-belt, synchronous belt, bushing, pulley, etc.).  Gates has not applied for UL approval of  v-belt or synchronous belt drive components.

Synchronous Belt Drives with a BANG!

During the startup of your synchronous drive you may occasionally hear a loud “Bang!” coming from the drive system.  This could be the result of belt tooth jumping, or belt ratcheting which is more prevalent in drives that are under-tensioned or have mismatched tooth forms. Though the installation tension may be correct and sufficient, ratcheting could still occur because of a loss in structural rigidity.  This is due to the fact that belt installation tension calculations do not take into consideration the possible differences in structural rigidity.  Therefore belts which appear correctly tensioned when idle may become under-tensioned when operating, or more specifically during the startup period. 

This belt ratcheting issue is more prominently in direct, across the lines starts in which severe shock loads are introduced to the system during this period.  This severe shock load results in frame deflection which, if the structural rigidity of the drive is inadequate, causes loss in belt tension and potential tooth ratcheting.

One method to determine if the structural rigidity of the system is of a concern is to simply stretch a taught piece of string between the DriveR and DriveN supports in such a manner that any significant movement will result in the string to sag or break.  This of course should be performed with the drive disabled and the proper lock out, tag out procedure followed.  Once the string is set, simply press both the tight and slack side of the belt together and monitor the strings movements.  If significant sag occurs then the structure rigidity should be increased or the belt installation tension will need to be increased above the recommended value.  This increase is used to account for the high startup loading and resist tooth ratcheting given this ratcheting can severely damage the belt and result in decreased belt life and performance. For any additional questions feel free to contact us at ptpasupport@gates.com or 303-744-5800.

2013 FIRST Scholarship

In support of the FIRST^® mission, Gates Corporation is offering six merit-based scholarships, each for $2,000, to select participants in the 2013 FIRST Robotics Competition. This scholarship may be used for any undergraduate science-based course of study at any United States college or university that holds accredited status. More information can be found online at www.gates.com/FIRST.

Eligibility

To be eligible for this scholarship, you must:

·         Be a senior in high school for the 2012-2013 school year

·         Have participated on a team during the 2013 FIRST Robotics Competition (FRC)

·         Provide evidence that your 2013 FRC team used a belt on its competition robot

Submission of Scholarship Application Package

Your complete 2013 Gates FIRST Scholarship application package must be submitted online, no later than May 15, 2013, 11:59 p.m. MST. Scholarship application packages submitted after the deadline will not be considered. Download PDF application and requirements online at www.gates.com/FIRST.

Application package includes:

·         A completed Gates FIRST Scholarship online application

·         A one page or shorter answer to the Gates 2013 Challenge Question, uploaded as a Word doc, PDF or image file

·         A one page or shorter letter of recommendation from an adult mentor/coach on your FIRST team, confirming the use of a belt drive on the competition robot and your participation in the 2013 FRC season, uploaded as a Word doc, PDF or image file

Gates 2013 FIRST Scholarship Challenge Questions

Part I: Describe the belt drive application on your robot. What advantages did it offer in solving the application challenge?

Part II: Gates belt drives can be found in everything from agricultural equipment, to zoom camera lenses, to now bicycles. Describe how Gates powers progress and impacts your everyday life.

Poly Chain Belts and Static Conductivity

Occasionally we get questions about using Poly Chain belts in a static safe environment.  The simple answer is don’t do it.  Our current Poly Chain belts use a carbon fiber cord.  This cord is static conductive, but the polyurethane that makes up the body of the belt is not.  This means that there is no way to guarantee electrical conductivity into the sprockets and then down to ground, which is necessary to dissipate the static electric charge that could build up in the system.

In the past, when the cord in Poly Chain was aramid, which is not conductive, the belts were sometimes used as an isolator.  This cannot be done any more either, as again, the current cord is carbon, and there is a possibility that an electrical charge could be conducted by the cord from one sprocket to the next.  In the rare instance where you need a belt to act as an isolator, this old construction can be ordered, but minimums and lead times will apply, and if you’ve never heard of a belt being used this way, chances are you don’t actually need it.  Like usual, please contact us if you have any questions.

Fastener Information for TaperLock and QD Type Bushings

Sometimes little things like shaft keys and bushing fasteners can halt progress when installing belt drive systems. Shaft key sizes were provided in an earlier blog post so sizes can be checked and key stock obtained before starting the installation process.  Lost bushing fasteners and wrench tool availability can also hinder progress.  Fastener sizes by bushing type and size can be found in industry publications, but not typically in concise form.

The following table provides fastener and wrench tool sizes for TaperLock type bushings ranging from the small 1008 size to the large 7060 size:

This information is very useful, as fasteners used with TaperLock bushings can be unusual and the wrench tools needed to tighten them may not always be readily available.  A hex bit socket set is needed for most TaperLock bushing installations.  And don't forget to have an appropriate torque wrench available so fasteners can be accurately tightened to the recommended torque levels.

The following table provides fastener and wrench tool sizes for QD type bushings ranging from the small QT size to the large S size:

Fasteners used for QD type bushings have hex type heads, so are quite common.  Hex type socket tools are generally available in most mechanics tool sets.  Again, don't forget to have an appropriate torque wrench available so fasteners can be accurately tightened to the recommended torque levels.

Don't let a lost fastener or an unexpected wrench tool size hinder progress when installing belt drive systems.  These tables are handy references for standard TaperLock and QD type bushing fastener sizes.  They also provide valuable wrench tool types and sizes as well as recommended fastener torque values.

Feel free to contact us at ptpasupport@gates.com or 303-744-5800 if you have any questions.

Gates Molded Notch V-belts Can Handle the Heat

Ethylene rubber is a robust material with excellent temperature and ozone resistance.  Several years ago, Gates developed and patented the technology to make ethylene rubber suitable for use in molded notch V-belts.

Gates latest molded notch single V-belt construction utilizes that patented technology to provide an allowable temperature range of -70°F to +250°F (vs. the industry standard of ‐30°F to +140°F).  The increased temperature range results in increased belt performance in high and low temperature environments. For more information on Gates molded notch V-belts, contact us at ptpasupport@gates.com or 303-744-5800.

Making the Cut: Long Length Poly Chain GT Carbon Belting

We are often asked what the best practice is for cutting our Long Length Poly Chain GT Carbon belting.  We have recommendations for not only the equipment used to properly cut the carbon fiber tensile cords with the least intrusion, but also for the location and manner in which the cut should be performed. 

The location along the belt span at which the cut is made can vary slightly depending on the clamping plate system used.  The best location to cut the belt would be in the span between two teeth given this results in the least material loss and decreases the likelihood of damage due to excess force.  In addition, the belt can be cut from the top of the tooth though care will need to be taken to ensure significant material deformation does not occur.  Finally, unless otherwise required, it is recommended to cut the belt parallel to the teeth given non-parallel cuts have the likelihood of damaging the tooth form of the belt and can cause unnecessary stress concentrations on the cut sections.

The tooling used to cut the Long Length Poly Chain GT Carbon belting at our testing lab is known as a “Guillotine Cutter”.  More specifically, a Model 600 Guillotine Cutter manufactured by U.S. Mold Machine Tool Co. is utilized (http://www.usmmt.com/).  The mode in which the Model 600 cutter applies the cutting force to the tensile cords within the belting is the most desirable given it is quick, has consistent forces and produces little to no heat.  It is not regularly advised to use a rotary cut off saw given this produces excess stress and friction on the belt which can causes the temperature to exceed the 185°F limit and result in damage to the belt.

Though each Long length belting application is different, these guidelines should get you on your way to getting your belt properly cut to size.  For any additional questions feel free to contact us at ptpasupport@gates.com or 303-744-5800.

NHRA Update: Double Win for Don Schumacher Racing at Arizona Nationals

At the recent NHRA Arizona Nationals (Feb. 22-24), Don Schumacher Racing celebrated a double win, with Tony Schumacher taking the win in Top Fuel, and Ron Capps winning Funny Car. Gates Corporation sponsors all the Don Schumacher Racing team cars. The win is Capps' 24th win with DSR and the 39th of his NHRA pro career. Capps with crew chief Rahn Tobler and assistant John Collins produced four runs Sunday between 4.037 seconds and the 4.064 he ran in the final. “This new car really likes to be planted early, and so Tobler (Crew chief) has been working on a new clutch package,” said Capps. “In (the final qualifying session Saturday), we finally found out what it really liked. And when you give Tobler a new combination that works, he’s going to ‘bracket car’ it to death,” he said of Tobler’s penchant for consistency. The combination of being runner-up at Pomona and Capps’ win Sunday moved the NAPA team to first in the Mello Yello standings after two of 24 events. “We’re starting to feel like we’re getting into the same rhythm that we were in last year when we went to six finals in a row,” Capps said. Schumacher's victory in Top Fuel was his fourth career NHRA Arizona Nationals at Firebird International Raceway and the 70th event title of his career. “The fans got their money’s worth on that run,” Schumacher said. “It was pedal, pedal, lift, pedal, straighten the car out, do it again. I loved it. It’s cowboy stuff. I enjoy that kind of race more than the record-setting ones we’ve had over the years. That still proves you have to put a driver in these cars and drive these things. We ran incredibly well all weekend. All you have to do is be a machine and do the same thing, win rounds and win rounds, but those runs are the ones that are just fun. The Top Fuel and Funny Car classes use Gates Poly Chain belts to drive the superchargers necessary to achieve the enormous horsepowers required to make the 1000' runs in 4 seconds or less. The Poly Chain belts are specifically engineered for the extreme conditions (shock loads, high loads, high accelerations, high speeds) of the application.

Horsepower Ratings

Determining a belt’s HP rating requires more than just knowing the belt type. Speed, pulley sizes, belt length, wrap angle, and other factors affect the HP rating. Speed affects the HP rating because as speed decreases, torque increases, so the HP rating must also decrease. Larger pulleys improve the belt’s HP rating because less tension in the belt is needed to transmit the torque. Synchronous belt HP ratings are based on having at least 60° of wrap and 6 teeth in mesh. V-belt ratings increase as wrap increases. HP ratings also include a length correction factor. Longer belts have higher HP ratings because they are used with larger pulleys and/or larger center distances, which decreases bending fatigue in the belt.

The easiest method to calculate a belt’s HP rating is by using our software Design Flex Pro or Design IQ. You can also use the tables and equations in our Drive Design Manuals. 

Belt horsepower ratings are used for designing belt drives. Always remember to design a drive with an appropriate service factor based on your application.

Gates Poly Chain Belts Power Courtney Force to Win in 1st NHRA Event of Season

Courtney Force, driving the Traxxas Funny Car with the John Force Racing team, won the Funny Car class of the first NHRA competition of the year, the O’Reilly Auto Parts NHRA Winternationals held in Pomona, CA. Gates Corporation is a sponsor of John Force Racing. “It was definitely unbelievable,” Force said. “My team, [crew chiefs] Ron Douglas and Dan Hood, thanks to them, they had given me a great race car all weekend long. I just try to keep it straight down the center, and they really made my job easy. I really owe it to those guys. It was kind of bittersweet finishing here [at the Automobile Club of Southern California NHRA Finals in November] and not getting that win, then coming back and picking up where we left off and finishing our job. We got the win, and I’m just proud of my team.” The Top Fuel and Funny Car classes use Poly Chain belts to drive the superchargers necessary to achieve the enormous horsepowers required to make the 1000' runs in 4 seconds or so. The Poly Chain belts used are specifically engineered for the extreme conditions of the application.

NAHBS - North American Handmade Bicycle Show

If you’re familiar with bicycles, you’re probably familiar with Gates Carbon Drive.  Gates Carbon Drive has been a viable bicycle chain replacement now going on 6 years.  Carbon Drive has made a pretty big impact on the industry, and a large part of the reason that they have been so successful is the adoption of the belt drive technology by small frame builders.  These builders tend to lead the industry to new ideas and solutions because of their ability to try new things, or change direction easily.  This month here in Denver, we are lucky enough to have a gathering of these frame builders at a show called NAHBS.  NAHBS stands for North American Handmade Bicycle Show.  Gates Carbon Drive is very excited to be a main sponsor of this great event.  Beyond just standard sponsorship, they are also hosting a design contest with more than $11,000 in cash and prizes to be given out.  NAHBS is open to the public, and a great way to see some beautiful and innovative bicycles.  If you’re in the Denver area the weekend of February 22^nd 2013, you should stop by.  Come shake hands with the employees of Gates Carbon Drive!  For show information please visit: http://2013.handmadebicycleshow.com/

ACHE Sprocket Corrosion

More and more often, synchronous drives (especially our Poly Chain GT Carbon belting and sprockets) are being utilized in ACHE applications.  Rust buildup is a common problem on the metal drive components of these cooling tower systems given the high ambient moisture content.  This rusting results in improper belt tooth meshing, premature belt tooth wear, loss of tension, and subsequent decreased belt life.

For these applications, nickel plating of both sprockets as well as rust resistant bushings are recommended to inhibit this corrosion and increase the belts performance and life.  For assistance in obtaining nickel plated sprockets and rust resistant bushings contact Gates Made-To-Order Metals team at (800) 709-6001.

Standard & Non-Standard Shaft Key Sizes

When preparing to install sheaves or sprockets using either TaperLock or QD bushings, it is helpful to know what key sizes will be needed so key stock material can be obtained in advance.  While this information can be found in various industry publications, it is not often presented in a direct and concise form.  The following table includes standard rectangular shaft key sizes for shaft diameters ranging from 5/16" to 9":

 Standard rectangular key stock is readily available from most Gates Industrial Distributors.

As bushing bores approach the maximum recommended diameters, keyway depths are reduced in order to extend maximum bores as much as possible.  Reduced keyway depths then require special non-standard shallow shaft keys.  Because these special shaft keys are not readily available, the appropriate size is included with each bushing.  The special non-standard shaft keys required for TaperLock bushings are included in the following table:

This table includes the specific bushing size that each bore range and non-standard shaft key correspond to for handy reference.

The non-standard shallow shaft key sizes used for QD bushings are not all the same as for TaperLock bushings and bore ranges differ, so the following table includes special non-standard shaft keys required for QD bushings:

This table also includes the specific bushing size that each bore range and non-standard shaft key correspond to for handy reference.

A valuable part of every installation job is obtaining all needed components and then confirming that those received are correct.  These tables will enable installers to quickly confirm shaft key sizes needed for both TaperLock and QD bushings over a broad range of bores.
Feel free to contact us at ptpasupport@gates.com or 303-744-5800 if you have any questions.

Gates and RoHS Compliance

RoHS is the European Union directive on the restriction of the use of certain hazardous substances in electrical and electronic equipment 2002/95/EC.

Gates can provide declaration of compliance letters for customers concerned with the RoHS compliance status of Gates belts and hardware. To obtain a declaration of compliance letter, contact Gates Product Application Engineering by phone at +1.303.744.5800 or via email at ptpasupport@gates.com.

Belt Drives and Radiation Exposure

Exposure to gamma radiation can be detrimental to the compounds used in rubber and urethane synchronous belts. Radiation degrades belt materials much the same way excessive environmental temperatures do. The amount of degradation depends upon the intensity of radiation and the exposure time. For good belt performance, the following exposure levels should not be exceeded:

Standard Construction: 10⁸ rads

Non Marking Construction: 10⁴ rads

Conductive Construction: 10⁶ rads

Low Temperature Construction: 10⁴ rads

Gates Poly Chain Belts Power NHRA

Gates is excited to be sponsoring two of the premier NHRA drag racing teams in 2013 - John Force Racing and Don Schumacher Racing. The two teams will be fielding both funny car and top fuel racing teams in 2013.

The 2013 season sees the debut of Brittany Force in a Top Fuel car - the first time that John Force Racing has fielded a Top Fuel car. We'll be following the teams and challenges through the upcoming season. The Poly Chain belt used for the Top Fuel and Funny Car supercharger drives is a special construction that allows it to handle the extreme shock loads, torque reversals, and speeds on the unique application. The extremes of the supercharger application help us as application engineers to understand the limits of our product, and push capabilities even further. Things that we learn about harsh loading and belt performance are then used to improve belt constructions and application expertise on demanding industrial applications. There aren't many industrial applications that get from 0 to 300+ MPH in less than 4 seconds though....