GENERAL: The resistance barrier shall be Model VR-6,
as manufactured by B&B Roadway, (888) 560-2060.
APPLICATIONS: The barrier shall be designed for use as a penetration resistance barrier and shall be suitable for use as a warning barrier for wide spans. The barrier shall be explicitly designed for traffic control on movable bridges, as required by AASHTO’s current Standard Specifications for Movable Highway Bridges, and shall be suitable for similar applications as well.
HOUSING: The operating mechanism and main control components shall be contained in a weatherproof housing. The housing shall be constructed of .375” (9.5mm) carbon steel, hot dip galvanized after fabrication. Exterior surfaces shall be painted aluminum. All external fasteners ½” and under shall be stainless steel. Fasteners over ½” shall be stainless steel, hot dip galvanized or mechanically galvanized. Arm shaft openings shall incorporate O-ring seals.
OPERATING MECHANISM: The warning arm shall pivot in the vertical plane via a mechanical 4-bar linkage. The linkage shall utilize cranks keyed to the main arm shaft and transmission shaft and an adjustable connecting rod between a pair of self-aligning spherical rod ends. The connecting rod shall be of AISI 4150. The linkage shall be driven by a fully enclosed, double reduction, worm gear speed reducer. Gear ratio used shall produce an operation time of 16 seconds. An auxiliary crank shall be used, paired with the transmission crank, to reduce the load on the transmission and to better balance and stabilize the load on the housing and mounting structure. The auxiliary crank shall be mounted in a permanently lubricated bronze bearing. The velocity of the arm shall follow a sinusoidal pattern to provide smooth operation. The arm shall begin and end its full motion path with zero velocity and accelerate smoothly to maximum velocity at mid-travel.
TRANSMISSION: The mechanism linkage shall be driven by a fully enclosed, heavy duty worm gear, double reduction speed reducer. the transmission shall have an occasional momentary peak load rating of not less than 30,000 inch-pounds. The output shaft shall be 2" in diameter. gear ratio used shall produce an operation time of approximately 16 seconds [option: contact factory for other speed options].
TORQUE LIMITER: For installations requiring heavy arms and/or high winds, a heavy duty torque limiter shall be provided to limit the torque transmitted to the operating mechanism due to excessive wind loads, physical obstruction to the arm or instant reversing of heavy arm assemblies. the torque limiter shall be capable of being set anywhere within a range of 10,000 to 75,000 in-lbs torque. each torque limiter shall be factory set for the load recommended by the manufacturer, based on installation requirements. each torque limiter shall be adjusted and tested at the factory, under over-load conditions, for a minimum of 5 minutes to verify the setting. the gate limit switch assembly shall be driven from the output side of the torque limiter so that slippage of the torque limiter will have no effect on the limit settings.
MOTOR: The motor voltage and phase shall be as specified by the customer. The motor horsepower shall be as recommended by the barrier manufacturer to suit the installation, typically 1hp. The motor shall be a C-face design and shall be mounted directly to the transmission. The motor shall be instantly reversing and overload protected.
LIMIT SWITCH: The barrier limit switch assembly shall be a self-contained unit. The assembly shall provide 8 independent SPDT control switches. [Option: a 10 circuit or a 12 circuit limit switch assembly shall be provided when specified.] Switches shall be rated for 15 amps, 480 VAC. Switches shall be controlled by individually adjustable cams. The limit switch assembly design shall permit adjustment of all cams with the barrier in any position. The limit switch assembly shall have a removable cover to help prevent accidental contact with switch terminals. Shaft, cams, bushings and housing pieces shall be of non-ferrous corrosion resistant materials.
BRAKING MECHANISM: The motor shall be equipped with a solenoid-release, automatic brake. The brake shall have a manual release lever to permit manual operation of the barrier during emergencies or setup.
ARM SHAFT: The main arm shaft shall be of 2.25” (57mm) diameter AISI 4150 with a minimum tensile strength of 140,000 psi. The shaft shall be mounted in heavy duty sealed ball bearings with lubrication fittings. [Option: arm shaft shall be chrome plated, when specified.]
DOORS: Front and rear access doors shall be mounted on full cross straps. Hinges shall be of the slip-off type and shall have stainless steel pins. A stop shall be mounted inside the door to secure the door from being raised off the hinges in the closed position. Door latches, two per door, shall use a vise action to compress a neoprene bulb-type gasket to seal the door openings. [Option: Door latches shall be of stainless steel and shall be tamper-resistant.] [Option: A stainless steel strap shall extend across each door and fit over a heavy hasp to permit use of a padlock. Strap and hasp shall be designed to fit both standard style heavy-duty padlocks and high security shackleless (“hockey puck” style) padlocks. Padlocks shall be provided by others, keyed alike.
ARM MOUNTING TUBES: A pair of carbon steel rectangular tubes, hot dip galvanized, painted aluminum, shall be rigidly affixed to the ends of the main arm shaft. The tubes shall be offset to locate the arm centerline at the height specified above the housing base. The tubes and a steel crossmember shall provide a sturdy mount for the arm and counterweights. the tubes shall have provision for easily adjusting the counterweight offset so the arm can be properly balanced in all positions.
COUNTERWEIGHTS: At the rear end of the side arm tubes, hot dip galvanized counterweights shall be mounted to balance the arm. Counterweights shall be sectional and shall be balanced at the factory.
ARM: The barrier arm design shall be one of the following: double rail aluminum tube (maximum 60’) [Option: Arm shall be tapered aluminum pole or trussed tri-rail aluminum tube (consult factory for specific design and maximum arm length).] Maximum arm length shall be measured from the centerline of the housing. Stainless steel truss cables and a damping type bumper rod shall be furnished with longer arms at the discretion of the manufacturer. Front and rear arm surfaces shall be covered with pre-striped alternating red and white diamond grade reflective sheeting. Stripes shall be 6” (150mm) wide and shall slope at 45 degrees down toward the arm tip. Remaining exposed surfaces shall be painted white.
ENERGY ABSORPTION CABLES: The barrier shall utilize 6x25 construction, 300-series stainless steel, annealed energy absorption cables to assist in diffusing the kinetic energy of an impacting vehicle. Cables shall be annealed in a coil not less than 42” diameter. The barrier shall typically be capable of absorbing the energy of a 5,000 pound vehicle traveling up to 50 mph. Actual capacity shall necessarily depend on individual barrier configuration.
ARM END LATCH: The energy absorption cables shall be anchored at the tip end of the arm in the closed to traffic position. A passive end latch mounted on the arm tip shall engage a rigidly mounted and anchored socket on or in a wall or post for independent barriers. For paired barriers, on-coming barrier shall be fitted with a bar and anchor nut while off-going barrier shall be fitted with a yoke. On-coming barriers shall be sequenced to close first and open last. Yoke on the off-going traffic barrier shall fit over the anchor nut in the closed to traffic position. End latch system shall be designed so that the yoke will engage the anchor nut in a collision to connect the two barriers into a continuous unit. End latches shall not require powered actuation for proper engagement.
MOUNTING: The barrier shall be fixed to a suitable foundation, as specified by the project engineer, using eight 1” (25mm) diameter anchor bolts. The barrier housing base shall provide 1.25” (32mm) mounting holes.
HANDCRANK: Both a hand crank and a drill crank shall be provided with each barrier to facilitate manual operation of the barrier.
SAFETY SWITCHES, TERMINAL BLOCKS AND WIRING: A manual disconnect switch shall be provided, pre-wired at the factory to break the main motor leads, to protect personnel during service. A handcrank safety switch shall be provided to prevent automatic actuation of the barrier during manual operation. [OPTION: Safety switches shall be installed and set at the factory to break the control circuit when either access door is opened. Door safety switches shall have a pull-to-override feature for test operation and shall automatically reset when doors are closed.] Control components and terminal blocks shall be mounted inside an electrical enclosure mounted facing the roadway side access opening, except where custom components required by the customer prevent this arrangement. Pressure-type, modular terminal blocks shall be fully labeled and clearly coded to wiring diagrams. All control wiring shall be clearly coded to wiring diagrams and shall terminate at the terminal block. Connections to screw-type terminals shall have lugs. Conductors shall be #16 AWG stranded, minimum. Wiring shall be run in conduit where practical.
OPTION: CABLE ANCHORAGE SYSTEM: [OPTION IN LIEU OF SIDE ARM LOCKS: The energy absorption cables shall be anchored at both ends of the span in the closed to traffic position. A cable anchorage system shall be used at the housing or base end of the arm to absorb loads during an impact. Details of the cable anchorage system shall be coordinated with the manufacturer to suit installation requirements.]
OPTION: ARM END LATCH ENGAGEMENT INDICATION LIMIT SWITCH: [Option (for barriers equipped with arm end latches): The arm end latch shall be equipped with a proximity switch to indicate correct engagement of the end latch. A trip mechanism shall be mounted as a single unit assembly on one barrier arm including the trip plate and switch. To ensure repeatability under service at all temperatures, trip plate shall not be mounted on the second barrier arm or separate anchor post/plate. Mechanism shall be fully adjustable and preset at the factory.]
ACCESSORIES AND MODIFICATIONS: All common accessories and modifications shall be available. Custom modifications and accessories shall be available through coordination with manufacturer.
WARRANTY: A 2 year warranty shall cover the barrier and related equipment against defective material and components. Manufacturer shall furnish replacement parts for a minimum of 10 years. Replacement parts for standard components shall normally be available within 1 working day. Lamps, fuses and other components designed for a life less than 2 years shall be covered for the rated life of the component or the warranty period of the component manufacturer.
PARTIAL LIST OF ADDITIONAL OPTIONS (contact factory for detailed specifications):
Stainless Housing
Arm Finishes, Striping Materials and Colors
Anchor Bolts (provided by manufacturer)
Alternate Arm Designs
Mounting Template
Arm Lights
Alternate Door Latch Styles
Flasher
Door Strap with Integral Heavy Duty Padlock Hasp
Reflective Button Delineator
Stainless, Tamper-Resistant Door Latches
Sidewalk Arm
Shear Pin Arm Base (for use as a warning gate)
Gong or Vibrating Bell
Don't see exactly what you need?
Contact us for more options and models not shown on our website and for surprisingly cost-effective customizations.
