Globe Life Field

Uni-Systems Engineering designed, supplied, and oversaw installation of the retractable roof mechanization and seals. The 12,000-ton roof panel is supported by ten steel trusses that span 620 feet between tracks on the north and south sides of the ballpark. A ten-bogie train on each track is powered by thirty 10-horsepower motors that drive the roof panel approximately 405 feet along the tracks. Each of the roof’s 120 wheels is supported vertically by two guided polyurethane segmented springs and laterally by four fused springs providing a smooth suspension system ride. Each bogie train is equipped with three rail clamp assemblies that act as parking brakes to prevent roof movement along the rail. Feedrails along the tracks provide power and communication via pick-up trolleys mounted to the roof panel. Compression bulb and flap seals protect the interface between the retractable roof and the fixed building to maintain the indoor conditions.

Uni-Systems Engineering developed the retractable roof’s custom operating system, which includes a programmable logic controller (PLC) and a human machine interface (HMI) accessed via a personal computer in the control room. The operating system also monitors all I/O devices so that any faulty component can be quickly and easily identified. The mechanical drive and electrical control systems are designed with multiple redundancies that assure the roof will remain operational while any faulty component is repaired or replaced.