The Boeing South Carolina Facility Custom Crane System
American Crane & Equipment Corporation is located in Douglassville, Pennsylvania, near Philadelphia. American Crane is a custom crane supplier specializing in engineered products for aerospace, commercial nuclear, DOE nuclear, NRF, and automated systems, and is known for tackling unique “critical lift” applications. American Crane also performs repairs, inspections, retrofits, and on-site maintenance as well as the sale of spare parts and standard equipment.
This project included the design, manufacture and installation of an 80 ton capacity custom Underhung Crane System with multiple bridges. These bridges can be interlocked to allow the trolley (carrier) to be transferred from one bridge to another throughout the system. The 460 ft x 1000 ft building is designed without columns, which allows 100% accessibility from the crane system.
Crane System Description
American Crane manufactured and installed the overhead crane system used in the Boeing South Carolina 787 final assembly building. There are 14 interlocking underhung bridges on the building runways. Twelve of the bridges are suspended in the main hanger bay, which is 1000′ long and 460′ wide. The main bay houses four (4) 1000′ runways each containing three (3) bridges. There are two auxiliary runways, one above the West mezzanine and one above the East mezzanine, with an underhung interlocking bridge on each runway.
The heart of the crane system is the three (3) “carriers” the operators use to lift airplane components. The carriers can move anywhere in the hanger runway system by transferring from bridge to bridge. The operator can link up to three (3) adjacent bridges together to lift very wide loads (tandem carriers 300′ apart).There are also four (4) 75′ long fixed carrier runways above the Southwest mezzanine used for carrier maintenance. In addition, a moveable work platform is used for workers to perform inspections, maintenance, and repairs on the bridges and runways.
Each carrier is controlled by an operator’s chair which has 10 joysticks and numerous switches and pilot lights. The operator moves the bridge, from which the carrier is suspended, using one of the joysticks. The lower carrier structure rotates 370º. There are two hoist beams which move in and out and are suspended from the lower carrier structure. Each beam has two underhung hoists with each hoist movable along the beam. Including the bridge and the hoist, each of the four crane hooks is movable along six axes. The hoists can be used singularly or in any combination up to a maximum of four (4). Each bridge can hold two 40 ton capacity carriers.
Electrical Control System
Each bridge and carrier is controlled by an on-board PLC (Programmable Logic Controller). The entire crane system is monitored by a separate Supervisory PLC installed in the maintenance area. This Supervisory PLC controls collision avoidance, emergency stop functions, and system status. Each axis of the six crane axes has an absolute positioning system accurate to 1/4”. The positioning system for the bridge and the carrier is a magnetic linear transducer type while all others use absolute rotary encoders. The Supervisory PLC also controls the adjacent linked bridges when multiple bridges are moved simultaneously. All crane inputs (limit switches, relays) and operator inputs are routed to the on-board PLC and mimicked to the Supervisory PLC. The on-board PLC then directs the motor controller (contactors or VFD (Variable Frequency Drive) in the appropriate crane movement. All the bridge E-Stop pushbuttons are hard-wired to the Supervisory PLC control panel through runway energy chain systems. The on-board bridge PLCs communicate to the Supervisory PLC through fiber optic industrial Ethernet cables also in the runway energy chain systems. The on-board bridge PLC relays the on-board carrier PLC communications to the Supervisory PLC. The on-board carrier PLC communicates to the bridge PLC via wireless industrial Ethernet waveguide system installed on each bridge.
The Supervisory PLC control panel is connected to a desktop PC with a color touch-screen monitor. This is the HMI (Human Machine Interface) for the operators and maintenance personnel to access the entire crane system status. Each carrier has an industrial integrated PC with a color touch-screen adjacent to the operator’s chair. This is the HMI for the operator to access individual crane (bridge & carrier) status dynamically and perform some high-level crane functions.
The bridges and carriers are powered by three phase 480 vac conductor bars which are installed on both the bridge runways and bridge girders. The bridges can be moved without a carrier using a local control panel with minimal pushbutton controls.
- Crane system has 14 bridges and three (3) trolleys (carriers).
- The main runway is 460 ft x 1,000 ft for a total building coverage of 460,000 sq ft.
- Project was complex with an aggressive installation schedule.
- Large capacity (80 ton) for Underhung Crane System.
- The system has three (3) trolleys (carriers) which have the ability to rotate +/-180 degrees. Each trolley (carrier) features two (2) single girder beams supporting two (2) 10 ton hoists on each, four (4) hoists total. Each hoist has its own trolley allowing for movement in all directions.
- Controls system has infinite position possibilities providing precision control. This allows for lifting objects of various shapes and difficult centers of gravity. The supervisory PLC/PC is located in the “maintenance barn” and communicates to the bridge PLC via Ethernet fiber optic network (7,800 ft of fiber optic cabling). The carrier PLC communicates to the bridge PLC via wireless Ethernet waveguide system (1,530 ft of waveguide).
- The operator chair is located in the carrier and is complete with a color touch screen which provides critical real-time information about the crane systems to the operators.
- System includes 1,216 bridge wheels, 216 bridge bumpers, 76 bridge end trucks, and 250,000+ pieces of hardware (such as bolts, nuts and screws).
- Runway contains 3.6 million lbs of steel (1,800 tons).
- The crane system can connect four (4) bridges together, creating a bridge crane with a span of 460 ft.
- Six 130 ft bridges: 141,000 lbs of steel each.
- Six 100 ft bridges: 116,000 lbs of steel each.
- Two 75 ft bridges: 103,000 lbs each.
- Entire project over 5 million lbs (2,500 tons) of steel.
- Installation was completed by assembling the bridge on the floor. A custom lifting device aided in lift actions and also served as a transport structure.
- The bridge and carrier absolute position is determined by non-contact linear transducers which use uniquely placed magnets in the bars along the runways to produce the position within ½ inch. There is 9,680 ft of transducer bars along the runways and bridges.
- The bridge uses energy chain (flexible cable track) for the hardwired E-stops and fiber cables to connect to the building wiring at the supervisory PLC. The chain lies in a metal trough for support along the building runway. There are two multi-conductor cables in each chain for each bridge, and every cable includes 12 copper wires.
- Total length of bridge entry chain is 6,150 ft.
- Total length of trough is 11,550 ft.
- Total length of multi-conductor cable is 12,300 ft.
- Total length of individual wires is 147,600 ft.
- The carrier uses energy chain to connect the moveable components together. There are 146 multi-conductor cables on each carrier.
- Total length of carrier energy chain is 700 ft (each carrier).
- Total length of multi-conductor cable is 7,300 ft (each carrier).
- Total length of individual wires is 55,300 ft (each carrier).
- Total length of flexible cables for the bridges and the three (3) carriers: 34,200 ft (over six miles).
- Wire in those cables: 313,500 ft (almost 60 miles).
For more information contact: Karen Norheim, Vice President of Marketing & IT1-877-877-6778 Ext. 227 or email at firstname.lastname@example.org