Chock Questions and Answers

Your questions are important. Chock or bracket questions? Ask

Question: Should I use two chocks instead of one?

Answer:  Yes! Two wheel chocks provide twice the protection of one (see Best Use).

Question: On a mine site. What should I use for my pickup?

Answer: OUT-R paired, orange urethane chocks are light weight, easy to see and compliant.

Question: Which chocks are required for my fire trucks?

Answer: HWG Super Grippers exceed all national standards for chock use fire apparatus.

Question:  My Corvette sits in a garage and I donít want anything to happen to it.

Answer: Simply parking? LRC-07. Lifting, jacking? HRG.

Question: I have a single axle camper trailer. Would 2 chocks be sufficient?

Answer: Yes - Unless you are concerned about potential motion on level ground. In this case, chock both ends of the axle on both sides of each tire. LRC-07 or LWG would be effective.

Question: Are aluminum chocks better than rubber wheel chocks?

Answer: Aluminum chocks generate coefficients of friction from transferring the forces from the axle to the rear teeth of the chock onto a small area that, in turn, creates a high psi or grip. Aluminum chocks keep their shape under extreme loads and will not diminish in height under pressure. Also, aluminum chocks are not affected by cold conditions.

Question: Why are rubber chocks effective?

Answer: Rubber chocks effectively grip with anything they contact except ice and snow.

Question: How do I choose between contour and pyramid rubber chocks?

Answer: Contours capture or fit the tire better than pyramid ones. Pyramid chocks work well considering they stop the rotation of the tire like putting a finger in a clock face. Pyramids transfer the load of the tireís forces vertically to the ground via a wide, stable base.

Question: I haul a backhoe on a dual-axle utility trailer. Which chocks are best?

Answer: RPA pyramids are a good quality, effective and inexpensive rubber chock for this use. HRX or HRG contour wheel chocks have better performance characteristics and fit the tire well.

Question: Our driveway is very steep, paved. What is the best chock to use?

Answer: Use HRMs or HRXs - unless there is ice and snow, then add LWGs or MWGs. Aluminum chocks have gripping power to keep wheels from moving, even at steep grades.

Question:  Should I place the chock directly against the wheel?

Answer: Yes. After an 8í roll on a 30% grade velocity can be as high as 3 feet per second.

Question: How do I calculate my percent grade?

Answer: Use rise over run. A 3 foot rise over 10 feet is equal to a 30% grade.

Question: Our loading docks require durable aluminum wheel chocks that will not cut tires or hands and that is easy to use. Which chock best?

Answer: Our HGSY is an excellent chock for this purpose. HGSY-EPR have added features that aid in visibility and ease of deployment. Consider chocking both sides of the trailer HGSY-EPL by adding a left sided chock to meet OSHA regulations. Driver friendly and enforceable!

Question: Our rubber chocks broke. Are there durable, economical chocks for loading docks?

Answer: LLC large laminated chocks are best suited for high volume, high capacity environments that are unfriendly to wheel chocks. Durable LLC can be punished 24-7-365.

Question: My cement mixer trucks are often on soft ground. What can I do?

Answer: You need a wide based chock to resist soil compression. HRR chocks would work well.

Question: Why is SAE-J348 important?

Answer: Society of Automotive Engineers standard for wheel chocks, SAE-J348, defines the forces a wheel chock can expect under extreme conditions. NOTE: SAE-J348 does not consider coefficients of friction or the benefits of paired usage.

Question: What is the EPDM material used in extruded rubber chocks?

Answer: EPDM is an acronym for a synthetic rubber, Ethylene Propylene Diene Monomer. EPDM has a saturated polymer chemical "backbone" which gives it excellent resistance to ozone and many other advanced chemicals found in today's environment. EPDM is a highly flexible and stable material that is perfect for very demanding environments.

Question: What is SBR rubber?

Answer: SBR (styrene butadiene rubber) is technical chemical: styrene-butadiene copolymer. SBR is an abrasion resistant material with excellent physical strength.

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