Introduction To Standards Testing Laboratories’ Machinery Division
In The 1970’s the company that is now Standards Testing Laboratories (STL) began testing tires for major tire manufacturers located in, and around, the rubber capital of the World; Akron, Ohio. Indoor laboratory testing of tires was relatively new at that time. Therefore, of necessity, STL designed and developed its own tire test equipment. This new equipment was used in our lab and sold to many of the World’s major tire manufacturers.
As in-door tire testing became more prevalent, STL worked with entities such as SAE and ASTM to develop new test procedures and new equipment.
As various governments began to issue recommended or required testing specifications, STL assisted by actively participating in groups, panels, and organizations to assure that machinery was available to meet these new test requirements.
STL now operates one of the largest independent tire and wheel test labs; in addition to manufacturing tire test machinery for worldwide use.
Following is a list of equipment available from STL:
A) Radial Endurance Machines---can test to international specifications:
FMVSS 109, FMVSS 119, FMVSS 139, CMVSS
ECE 30, ECE 54, ECE 106, ECE 324
SASO GS 53-8, SASO GS 53-9, SASO GS 646-5
JASO T203-85, JASO C608-75
ABNT NBR 6751-4.1.2
ISO 3006, ISO 3894, ISO 10191-5.3, ISO 10191-5.4, ISO 10454-5.2, SAE J267, NOM and others.
B) Strength Test (Plunger) Machines ---to international specifications:
FMVSS 109, FMVSS 119, CMVSS
ECE 30, ECE 54
SASO GS 53-7, SASO GS 646-4
ISO 10191-5.1, ISO 10454-5.1, NOM and others.
C) Bead Unseat Machines --- to international specifications:
FMVSS 109, FMVSS 119, CMVSS
ECE 30, ECE 54
SASO GS 53-10
ASTM F2663, NOM and others.
D) Drop Impact Machine --- to international specifications:
FMVSSJASO T203-85, JASO C608-75
E) Rotary Fatigue Wheel Test Machines (Bending moment, Cornering)
JASO T203-85, JASO C608-75
ISO 3006, ISO 3894
F) Rotary Fatigue Wheel Test Machines (for tire and/or wheel damage)
In addition to the SAE wheel test noted above, this machine is currently under study for a possible new ECE tire road hazard regulation.
G) Tire Rolling Resistance Test Machines---international specifications:
ISO 28580, ISO 18164, ISO 8767
SAE J2452, SAE J1269, SAE J1270
GB/T 18861-2002, Smart Way Program and others
BUILDING YOUR OWN TIRE AND WHEEL TEST LAB?
For companies interested in establishing their own complete tire and wheel testing laboratory, STL can provide our proprietary equipment listed above. We can also assist with; all other equipment needed for a quality tire test lab, layout your new lab, start-up your new lab, and establish and train your personnel in good lab procedures for your future success.
Some of the additional equipment found in a quality tire test lab include: tire oven (STL), air permeation box (STL), tire water burst equipment (STL), high speed free spin machine (STL), tire mounting machine for passenger and light truck tires, tire mounting machine for truck/bus tires, tire balancer, weigh scales, air compressors, tire sectioning saws, tire mounting adapters and adapter racks, rim/wheel storage racks, and assorted hand tools and gauges. X-ray and Shearography are also available.
For wheel testing, we recommend radial fatigue (STL), rotary fatigue (STL), torsional fatigue machine (STL), and a dye penetration booth for detecting wheel damage after testing (STL).
STL DESIGNED EQUIPMENT IS SHOWN BELOW:(Click next arrow to see more)
RADIAL ENDURANCE TIRE AND WHEEL TEST MACHINE
Radial Endurance Machines can be custom designed in a range of drum sizes (1708 mm, 2000 mm, and 3000 mm are common sizes). Load applied can range from 5 kg to 100,000 kg depending upon your needs. Speeds can range from 2 km/hr to as high as 496 km/hr.
All endurance machines are PLC control and have a choice of the following options: tire rolling radius, tire air pressure control, tire inside temperature, air blowers for wheel testing, AC or DC motor and drive, customized levels of safety guarding, choice of hydraulic or servo-motor loading, spindle brakes, cleats (thumpers) and custom paint if desired.
The standard STL Radial Endurance Machine includes redundancy circuits built into the safety E-stop, is made to comply with fire codes NFPA 70 and NFPA 79, uses NEMA 12 panels and has wiring to UL 508A standards. Additionally, the STL machine uses a forged ring for the drum surface and dynamically balances high speed drums to meet ISO 1940 G2.5 (the balance level used for gas and steam turbines). This preserves bearing life and permits more accurate speed control. The STL radial endurance machines also include surge protection devices.
STRENGTH TEST and FOOTPRINT MACHINES
Strength Test (Plunger) and Footprint Machines are available in sizes commonly used for FMVSS and ECE testing, but are also available for R&D purposes up to 45,000 kg load. The standard machine will chart a load/deflection curve. STL can also custom design this type of machine to permit measurement of static lateral, longitudinal, and torsional forces if desired.
BEAD UNSEAT MACHINES
Bead Unseat Machines are specifically designed to comply with individual international test specifications. The standard STL machine is equipped with a 19mm, 32mm and 38mm plunger. Our machine is also equipped with the three newly designed ASTM bead unseat blocks Type 2A, 2B, and 2C. (The new blocks are designed to work well with new large diameter custom wheels up to 30”)
Load can be applied by your choice of hydraulic or servo-motor. The STL machine design uses mounting cones similar to a standard tire/wheel balancing machines; multiple wheel adapters are not needed. This results in considerable time and monetary savings.
DROP IMPACT MACHINE
The Drop Impact Tester was designed to meet the requirements of SAE J175 wheel tests. We have also found it helpful for certain radial tire sidewall puncture tests; referred to by STL as “corn stalk puncture test”.
The machine comes standard with a 13 degree base. Also available are an SAE spring striker, 30 degree base, 90 degree base, impact velocity measurement system, and various tire air systems.
ROTARY FATIGUE WHEEL TEST MACHINE
The STL Rotary Fatigue Wheel Test Machine is an extremely heavy duty machine designed for long term use in a harsh environment. This is a rugged piece of equipment. The machine is controlled by a PLC which permits step testing, pre-set cycle counter, excessive deflection shutdown, and variable speeds. Maximum speeds to 750 rpm only.
ROAD HAZARD IMPACT MACHINE by STL
STL participated with SAE in the early test phases of this concept. Originally for testing wheels, the machine is becoming more popular in recent years for testing tires. As you can see in the photos above, STL has developed several alternative striker heads capable of creating various types of tire failures (the original SAE striker head is shown in the lower left corner of the accessories photo above).
STL found the original concept and pendulum design to be too limited. Developing a more automated lifting method, adding a functional braking mechanism to limit rebound strikes, and including angle adjustments on two axes resulted in violating the overall weight and geometry of the SAE pendulum arm. We believe that a more sophisticated test method is to accurately measure the speed of each impact and create a simple formula for each individual machine that properly calculates the impact energy. There are currently few of these machines in operation and, to our knowledge, none of them have identical pendulum center of gravity, center of percussion or moment of inertia. Calculating the properties of each pendulum and generating the true impact energy for a particular machine is the proper method for comparing results between the various machines in operation. Similar to tire rolling resistance machines, each individual machine is consistent and repetitive but no two machines have identical pendulum characteristics. Only by targeting the impact energy can test data from different machines be compared. Of course, in-house R&D would always be directly comparable since all tests would be run on the same machine.
The STL machine is capable of drop angles as great as 176 degrees, striker angles of + 30 degrees on the X axis and + 42 degrees on the Z axis, pendulum end weight adjustable from 54 kg to 94 kg, and the STL machine includes your machine’s specific impact formula programmed into the machine’s laptop computer. Impact energy will be given for each impact.
ROLLING RESISTANCE MACHINE for PC, LTR, and TBR TIRES----can be FORCE or TORQUE METHOD ---- or both
FORCE METHOD with heat insulator and servo-motor loading.
One of STL’s 20 year old lab machines for Rolling Resistance testing.
TORQUE METHOD ---- still meets all international accuracy standards
STL does not simply make tire rolling resistance machines; we run tire rolling resistance machines in our own test lab, every day. We maintain three (3) RR test stations running almost constantly. STL has two (2) stations using the Force Method and one (1) station using the Torque Method. My personal preference is the Torque Method.
To my knowledge, current regulations for labeling tires exist only in Europe and Japan. The USA has yet to complete their studies and issue a rolling resistance regulation.
Europe has two basic steps to qualifying and labeling tires for sale. First the tire supplier must qualify a tire line through “type approval”. Type approval does not take into consideration the difference in rolling resistance results generated by each individual RR test machine. For type approval your RR machine does not need to be aligned to any reference machines.
The second step to labeling tires for sale in Europe is to have your machine aligned to one of the 10 or 12 reference machines. The result will be a formula to be used to correct your machine’s numbers to reflect what is believed to be the true RR number for a given tire. This true RR number is thought to be the average generated for that specific tire if all 10 reference machines where to test that tire. In essence, Europe has decided that the average RR number generated by all 10 reference machines for a given tire is the true RR number for that tire. Alignment for European labeling is an expensive procedure.
Bridgestone- Japan has "alignment tires" (2 sizes) manufactured by Bridgestone and assigned a pre-tested rolling resistance numbers that can be used to compare your un-aligned machine with the Bridgestone machine. This will not qualify your machine for European labeling, but will help in understanding the relevance of your machine's test output numbers. Currently, these two alignment tires are available at www.jatma.or.jp/english/labeling/contact.html Find "Related Documents link” at bottom of page, then click on “ARRRT Basic Condition and Procedures/Request for Quotation"
When purchasing a tire rolling resistance machine, it is important to clearly understand that each different RR machine can generate a different RR number for the same tire. It is the repeatability of your machine that is of ultimate importance. Your new machine must be consistent and give repeatable results over long periods of time. This repeatability is what allows alignment between machines.