Tubular locks are not to be confused with those similar to them, such as wafer tumbler locks, cylindrical wafer tumbler locks and pin tumbler locks. Tubular locks are used in the creation of elevator locks, locks for coin-operated washing machines, locks for vending machines, ATM locks, Kensington computer locks and bicycle locks, including the Kryptonite lock.
Tubular locks have a ring-shaped hole in the middle of the keyway. In the middle of this circular hole is placed a solid metal cylinder. Inside the gap between the cylinder and the keyway hole are six to eight pins. In a sense, tubular locks encase the bolt within a tube. Tubular lock pins are held in place by plugs that rest in the cylinder, as do driver pins and springs. While tubular locks usually have between six and eight pins, they may also have as few as four or as many as ten.
To work, a round key that is open in the center is inserted into the lock. The key has rectangular notches cut around its edges that correspond to similarly shaped plugs. When properly inserted, each notch depresses an individual pin to a certain height. In doing so, the lock cylinder is able to turn freely. While basic pin tumbler systems use pins that move vertically when pushed, the pins of tubular pin tumbler locks move horizontally when pushed.
Tubular locks are often mistakenly considered to be more secure than other types of locks, because they are used so frequently with coin-operated machinery. In fact, however, they can be picked fairly easily using a special tubular lock picking tool, the back end of a ballpoint pen or a hole-saw drill bit.
To combat the possibility of theft, manufacturers may either machine the middle pin of a lock with hardened steel or with a ball bearing in its center. However, tubular locks are still not recommended for high security applications.
To determine whether or not tubular locks are right for your application, reach out to a well-versed lock manufacturer with the details of your operation.