Category: Decontamination > Mechanical Surface Removal > Scabbling , Mechanical
Reference # : Model No : WallWalker 3D
The WallWalker system consists of four major subsystems: a motion control subsystem, a heavy-duty scabbler work head, an ultra-high performance vacuum system and a monorail mounting system.
The motion control subsystem consists of a system controller, operating software, DC brushless servo motors and the servo motor controllers. The heart of the motion control subsystem is the system controller and operating software. The WallWalker system can be configured with a variety of controllers. The current system utilizes an IBM ThinkPad laptop computer on a Windows 95 based program.
The operating software allows the user to control the work head's position and define it's path of movement. The scabbler head can be "steered" using a manual up-down-left-right movement or can be moved along a predefined path (e.g. straight line, horizontal raster pattern, circle). The control software provides on-line help, as well as extensive error trapping to ensure that the operator does not move the head to an inaccessible or unsafe area.
The scabbler head subsystem is designed to remove lead-based paints, radioactive and other hazardous contaminants from vertical surfaces in an environmentally safe manner. The scabbler head contains three single-piston scabblers mounted on an independent suspension. To provide an even surface profile, the three scabblers can be rotated. The scabbler's rotation direction and speed are controlled via the scabbler control unit.
The VAC-PAC ultra-high performance vacuum system offers two stage positive filtration sufficient to support safe and efficient removal of radioactive and hazardous materials. The first stage roughing filter efficiency is 95% at 1 micron, with a second stage HEPA efficiency of 99.97% at 0.3 microns. The VAC-PAC features automatic self cleaning of the first stage filters using reverse-flow pulses of high pressure air. This exclusive feature virtually eliminates filter clogging, and allows for continuous vacuuming without interruptions or operator exposure due to filter replacement.
The monorail mounting subsystem is designed for quick repositioning of the WallWalker's motors along the wall.
Two important safety features have been incorporated in the positioning trolleys. First, there is a solenoid-controlled brake pin on each trolley to ensure that it remains fixed in position during operations. The brake pins are controlled using an AC voltage and can be engaged and disengaged using a toggle switch on the scabbler control unit. The trolleys also incorporate proximity switches to ensure that the brake pin is fully engaged.
Unit is remote controlled and easy to operate. Unit is not labor intensive.
Vacuum unit minimizes need for respiratory protection for operating personnel.
Unit is very maneuverable.
The design of the monorail allows the scabbling unit to move quickly from one section to another section, thus benefiting decontamination on large areas.
When used in small areas the removal gaps are considerably large.
Mobilization procedure is lengthy.
Walls have to be drilled all the way through the other side in order to set up the monorail system.
In some locations the coating on the mortar joints was not completely removed.
WallWalker™ scabbling head on cart used to move it to work area