FAB Consultants & Engineers [P] Ltd. Manufactures Motorized Roller Conveyor and Gravity Roller Conveyor. FAB Consultants & Engineers [P] Ltd. Is an ISO 9001: 2000 certified company. The Motorized Roller Conveyor and Gravity Roller Conveyor are used in various industrial applications. The Motorized Roller Conveyor and Gravity Roller Conveyor is especially designed for conveying heavy items like cartons, bins, and machinery parts. This system when fitted with steel rollers [idlers] works on principle of gravity.