Solving the Width Restrictions with Most Personnel Mine Doors
Not all mine door applications are equal. AMD recently completed a unique project for a personnel door. The client presented an application that required more than your typical 3-foot (.91m) width for a concave man door.
The client was extremely specific in not wanting a traditional underground personnel access door for this unique application. The personnel doors were needed in a high traffic location underground with ease of access for more than one miner at a time. The problem the mine was encountering was that most underground personnel doors limit access through the doors to one at a time, single file only, with little to no clearance for carrying additional tools and supplies.
Extended Width Personnel Door
Most underground pedestrian door dimensions are limited to approximately 3 foot (.91m) to 3.5 feet (1.06m) in width. This client requested to double the width! This extended width door would give ample space for miners to travel in pairs through the doors with additional supplies as needed. The other major challenge was for the doors to be safe operating at 14” water gauge (1372 pascal) air pressure resistance! We agreed on new free and clear dimensions of 6 foot (1.82m) wide x 7 foot (2.13m) high. AMD Engineering went to work.
AMD Engineering Selecting the Correct Door Design
AMD Engineering started with its AMD patented Opposing Swing Pedestrian Door and extended the width out to 6’ free clearance. The opposing swing design is ideal under this 14” water gauge higher pressure application. One door wing panel opens against the air flow while the opposing wing opens with the air flow. Both wings are tied together with a top mounted connecting bar.
The “balanced” design uses the mine’s air pressure to assist with the opening of one side while balancing the resistance on the opposite side wing panel. By using the energy from the existing air pressure, the pedestrian door requires minimal efforts to open/close which is essential when manually operated.
Important safety note: the doors do not “slam” shut or lunge when opening. This unique design utilizes equalized air pressure to assist the door in opening and closing making them highly efficient and safe.
AMD Finite Element Analysis (FEA) Modeling for Safety
Next AMD engineering went through the process of calculating the amount of force placed upon the proposed personnel door, using water gauge, height, and width to determine the amount of force and stress placed on the door. AMD needed to assure the client it would be safe under these conditions. No exception, AMD will always view any new design with safety first and foremost. The extended width design had to prove safe under these operating conditions.
AMD Engineering conducted a Finite Element Analysis (FEA) modeling process to analyze the expanded width design based on the real underground conditions at the
AMD Improvements and Modifications from the Results of the FEA study
The FEA Study Data results clarified what improvements and modifications were needed to assure confidence and reliability for safety. AMD improvements included:
- Adding a more robust door closer device
- Upgraded seals around door for high air pressure
- Redesigned and upgraded heavier duty door hubs
The final design resulted in a PE stamped validation of the extended width design at 6′ Wide x 7’ high Free and Clear. See the finished product below from both sides of the door.
AMD Designing for a Safer Underground Environment
AMD demonstrated and proved a new solution utilizing an existing AMD design to satisfy another underground mine client.
Contact AMD to find out if this solution is right for you. We want to hear about your unique challenges to your ventilation problems
