Engineering Specification for the Safe-Crossing Barrier Gate
I. General
- The Safe-Crossings Barrier Gate is a patent pending telescoping gate that will extend from 20’ to 50’ by manually pulling out two (2) interior gate arms.
The outer gate arm is 20’ long and each interior section can be pulled out to a maximum of 15’ each. It is recommended that each of the two interior gates be pulled out the same distance. (For example on a 40’ gate, the outer gate is 20’ and each of the interior gates should be pulled out 10’ each.) - The Safe-Crossings Barrier Gate is constructed of anodized aluminum which will not oxidize and provides an attractive surface hardening.
- When in the home position, the gate is a compact 20’ long and will withstand wind loads up to 100 mph without fatiguing. (Longer gates generally made of wood, fiberglass, or metal will snap at wind loads of 40 mph or greater).
- Red and white reflective diagonal stripes are provided and compliant with FHWA standards. All reflective tape is “Type III High Intensity Engineering Grade”.
II. Specifications
- Length – Overall retracted length of the Safe-Crossing Barrier Gate will measure 20’. The extended gate can measure from 20’0” up to 50’0”. Extended length is specified by customer and appropriate locating holes are drilled into the gate arms so “T” handle pins can be inserted to “lock” gate arms in place at the desired length.
- Design – The Safe-Crossing Barrier Gate is designed in three sections - the Outer, Middle, and Inner Gate Arms. The Outer Gate Arm serves the purpose of housing the two interior gates and also provides a means as a connection point to adapt to pivoting arms and counterweight system. The two inner gates slide on UHMW (ultra high molecular weight) polypropylene pads for smooth and uninterrupted travel when either pulling the gate arms out or nesting them in their home position.
As noted above, the customer will specify the desired length of the gate and Safe-Crossings will drill locating holes in each arm. As the gate arm is pulled out, indicators are visible as the desired length is being approached. Once final alignment is made a “T” handle pin is placed into the holes to “lock” the arms in place. This procedure is done for each of the two inner gates.
The Counterweight Design is very unique. With all three gate arms fully nested (20’ long), the gate arm will automatically ascend to the vertical position – no need for manual lifting or mechanical devices. To lower the gate to the horizontal position, it will require approximately 5 – 10 pounds of force to pull the unit down. Once the gates arms are pulled out, it will naturally stay in the horizontal position. Stops are provided on the pivoting arms to always maintain a true horizontal position. - Weight – The Safe-Crossings Gate weighs 84 pounds +/- 2 pounds. Installed with three (3) optional solar powered lights the gate weighs 87 pounds +/- 2 pounds.
- Temperature Range – All materials used in the construction of the Safe-Crossings Barrier Gate arm will operate from -30 degrees F to 160 degrees F.
- Lubrication – All components of the Safe-Crossings Barrier Gate are specified as self lubricating or no lubrication required. This includes all bushings and sliders used in the manufacture of the telescoping gate.
- Solar Powered Gate Arm Lights (Optional) – Each light unit has a 0.4 watt solar panel and 1200 MA nickel hydride cells and will operate for three (3) nights on a 6 hour sun charge. The light is FHWA approved and can be operated in a Steady Burn or in a Flashing state (approximately 60 flashes per minute). A built-in photo cell that will automatically turn the lights on as evening approaches and shut the lights when the sun rises. Each lights is turned on and off manually, but an optional mercury switch can be retrofitted for automatic operation. In this mode, anytime the gate is placed in the horizontal position, the solar lights will be activated and when in the vertical position, the light will always be inactive.
III. Gate Sections
- All three gate sections are proprietary extrusions using aluminum alloy temper 6061 with a 215R1 clear anodizing and there may be slight traffic and handling marks on the outside surfaces.
- The gate, when fully extended, shall withstand a side wind load of 100 mph.
- The Outside Section nominal dimensions shall measure 20’ long and the profile shall measure 5.333” x 3.063” with a wall thickness of .125”. Special channels and ribbing are designed on the interior of the gate arm to provide added strength and channels for additional hardware.
- The Middle Section nominal dimensions shall measure 18’ long and the profile shall measure 4.597” x 1.750 with a wall thickness of .080”. Special channels and ribbing are designed on the interior of the gate arm to provide added strength and channels for additional hardware.
- The Inner Section nominal dimensions shall measure 17’ long and the profile shall measure 4.000” x 1.000 with a wall thickness of .083”.
IV. Hardware
- All metallic fasteners which include a variety of screws, bolts, nuts, washers, etc. shall be 18-8 Stainless Steel. Rockwell hardness is B85. Minimum tensile strength is 85,000 psi.
V. Reflective Tape
- Both sides of the Safe-Crossings gate shall have reflective tape the entire length of the extension. Red and White diagonal stripes compliant with FHWA standards shall apply. All reflective tape shall be “Type III High Intensity Engineering Grade”.