Panama Canal locks
The total length of the lock structures, including the approach walls, is over 1.9 miles (3 km).
In this usage pattern, the paired locks offer redundancy during maintenance or in the event of mechanical issues.
The center wall between the chambers is 60 ft (18 m) thick and houses three galleries that run its full length.
The lowest of these is a drainage tunnel; above this is a gallery for electrical cabling; and toward the top is a passageway that allows operators to gain access to the lock machinery.
This arrangement has the effect that the force of water from the higher side pushes the ends of the gates together firmly.
This design allows for the transit of smaller vessels less than 600 ft (183 m) long, such as canal tugs, without using the full quantity of water.
[6] The auxiliary gates were originally incorporated because the overwhelming majority of all ships of the early 1900s were less than 600 ft (183 m) long and therefore did not need the full length of the lock chamber.
These mules are used for side-to-side and braking control in the locks, which are narrow relative to modern-day ships.
[11] The mules themselves run on paired 5 ft (1,524 mm) broad gauge railway tracks.
The track inland is used to return the mules to their starting point and does not have racks except on the steep inclines between lock chambers.
[10]: 23 Traction is by electric power,[12] supplied through a third rail laid below surface level on the land side.
These fender chains featured elaborate braking mechanisms to allow a ship of up to 10,000 tons to be safely stopped.
With many modern canal users weighing over 60,000 tons, and given the expense of maintaining them, the fender chains were reduced in number in 1976 and finally removed in 1980.
Mechanical interlocks are built into the controls to make sure that no component can be moved while another is in an incorrect state—for example, opening the drain and filling the valves of a lock chamber simultaneously.
The quantity of material needed to construct the locks required extensive measures to be put in place to handle the stone and cement.
85 ft (26 m) high towers were built on the banks of the canal, and cables of 2.5 in (6 cm) steel wire were strung between them to span the locks.
The smaller constructions at Pedro Miguel and Miraflores used cranes and steam locomotives in a similar manner.
