Balanced Chocking:

The use of chocks on four tires provides balanced restraint to the center of gravity of the vehicle. This eliminates the extreme lateral forces (induced by longitudinal forces) inherent to chocking systems applied only to one side of the vehicle. Vehicles of one ton capacity or more (including dual wheeled) will require a total of six chocks, four on the front axle and two behind the rear axle.

Longitudinal Restraint
The chock face slopes 60 degrees from the horizontal and can be vertically adjusted to contact the tire tread at a point 30 degrees below the horizontal plane through the axle center, providing effective chocking restraint for all tire sizes, from 20"to 36"diameter.

Lateral Restraint
The vehicle side flange faces on the chocks protrude behind the vehicle tires preventing lateral motion in one direction. The lateral face on the chocks opposite on the same axle prevents motion in the opposite direction.

Vertical Restraint
The use of vertical restraining straps, etc. is not required for rail service restricted to 6-MPH longitudinal impacts.

Flexibility / Adjustability
Applies readily for all vehicles and tires including those with dual rear axles, as the outside wheels of a dual are not chocked. The peg board type grating and the dual cam design of the chock allows incremental longitudinal positioning of 3/4 of an inch. Three chock height settings, at 4-1/2", 6-1/4"or 8"can be selected to suit tire size and vehicle ground clearance.

Simplicity of Operation
Lightweight plastic chocks (7 lbs) engage with deck grating-using cam engaged positive lock latching. No tie-down straps are used, eliminating awkward fitting over tires and the tightening operation required with such straps.

Adverse Conditions
Deck grating is readily clearable of snow and debris by use of hinged panels that are simply pivoted up towards a rail car's side screening to allow the deck to be swept, blown clean or shoveled. As there are no tie-downs incorporated in the system, there is no vertical loading of the chocks and the grating needs no latching to hold it down.

Secure Storage
Chocks apply directly to storage panels mounted low on the rail car side screening where convenient and to provide maximum working and door opening clearances. Chocks should be stored in the collapsed position to occupy the least amount of space.

Low Cost Rail Car Installation
No deck preparation is required before installation No welding is required to affect the installation No painting is required after installation Specially designed two piece inter-locking piano style hinging runs full length of the rail car deck. Proper spacing of grating panels is therefore assured. Alignment plates are available to assist crews in correctly aligning the panels, one to the other.

© 1999 Holden America Inc., All rights reserved.