MAdoors Systems hydraulic rising bollards are designed for high security vehicle entrances, army, industrial, governmental and commercial buildings or streets which are closed to vehicle traffic between certain hours of the day. Both "High Security" and "Commercial" type Madoors Hydraulic Rising Bollards have the same strength, whereas "Commercial" bollards are shorter than the "High Security" ones. The thickness of the bollard, the underground construction, the self-lubricating sealing and guide ring made of special plastic types, hydraulic piston, flange thicknesses and diameters, hydraulic connections, installation and drainage procedures etc. are all the same. These units are designed to K12 standards. Finite element analysis can be supplied upon request. Typical raise/lower time is 3 seconds but it is possible to design the system to raise/lower in 1 seconds.
Surface Mounted Bollards
This type of bollard uses some sort of anchor system, usually mechanical, to mount the bollard to the surface. Although this is an inexpensive method of installation, it also is not a very secure method. Upon impact, the anchors are often the weakest link and quickly give way, leaving a tilted bollard and damaged foundation. However, when the purpose of the bollard is more to provide a mere presence or psychological barrier, this type of installation is most cost effective. It also may be necessary to use shear bolts in a post-tensioned concrete structure in order to prevent impact to the bollard to potentially compromise the building.
The next type of bollard, the rebounding bollard, is often surface mounted, but overcomes the strength and damage issues associated with standard surface mounted bollards.
Retractable / Removable Bollards
Not all applications for bollards are intended to be permanent or always prevent access. As such, retractable and removable bollards have been designed to allow the owner or a potential traveler access the area normally denied by the bollard.This is typically done in one of several ways. The lowest technology is the pipe-in-a-tube method where a socket is created in the ground. The bollard can then be removed from the socket when access is to be granted. This is inexpensive, but requires manual intervention to access the area.
Automatic hyadraulic rising bollard barriers , A second way is through the use of pivoting bollards. A locking pin is used to hold the bollard upright under normal circumstances, and removed to allow the bollard to lay flat when a vehicle is to pass over it. These bollards are generally flat in shape to allow for vehicle clearance. Often, the pin is locked in place with a padlock to prevent unauthorized access.
Finally, the most expensive method is the automatic retractable bollard. Usually hydraulic powered, the bollard actually retracts straight down into the ground and becomes flush with the surface during access. Actuation of a hydraulic bollard can be by any number of methods, from security guard push button to remote controls and toll booth pay systems.