Also Known As: Cylinders
DESCRIPTION
Cylinders are typically operated by keys, which are what operate 98 percent of locked or secured doors today, although as the cost goes down and newer technologies and types of electrified locking devices become available, that percentage will continually shrink.
Cylinders are manufactured as a housing and plug with pins and springs that move when a key is inserted. This must create a consistent shear line, which allows for the key to rotate the plug in the hous- ing, turning the tail piece of the cam, in turn allowing the latch or deadbolt to be retracted or extended to open or secure the locking device and door.
The triangular shapes that appear as peaks and valleys at different distances across the key are known as the blade, and the part of the key that sticks out of the cylinder is the bow. The peaks and valleys match the different pin sizes inside the cylinder, and the springs are installed underneath the pins to give them tension when the key is inserted.
PROPERTIES
Mechanical cylinders are typically manufactured with a metal housing that has a plug, which is where the key is inserted, along with springs, pins, and a cam to operate.
Electronic cylinders are available from some manufacturers where, in addition to the mechanical components of a cylinder, there is an electronic component that needs to match the key as well, sending a signal between the key bow and the cylinder to ensure the key is intended to open that particular cylinder. Basically, this is a second level of security to verify that the mechanical key is not an unauthorized duplication.
Cam
With the rotation of the plug also comes the rotation of the cam on the back of the cylinder, which operates the locking device itself. The cam is a small piece of metal that has a particular shape to
FIGURE 2.19 Cylinder Cam
(Source: Courtesy of SARGENT® Manufacturing Company)
FIGURE 2.20 Cylinder Cam
(Source: Courtesy of SARGENT® Manufacturing Company)
FIGURE 2.21 Cylinder Cam
(Source: Courtesy of SARGENT® Manufacturing Company)
FIGURE 2.22 Cylinder Cam
(Source: Courtesy of SARGENT® Manufacturing Company)
operate the specific mechanisms inside of a lock body or chassis, in order to rotate and trigger the proper operation of the locking device.
Finishes
Depending on the manufacturer, cylinders are typically available in all architectural finishes to match the other specified hardware on the opening.
Painting cylinders or anything on site is not recommended as it will contribute to poor air quality for those working in the space. Using a manufacturer’s factory finish might even help contribute to credits toward a current or future green building standard, code, or certification.
Collar
A cylinder collar surrounds the cylinder between the its face and the door or surface upon which it is installed. The collar provides the separation or acts as a spacer so that there is no void and the cylinder sits flush against the door. Without the collar, the cylinder might be exposed for tampering.
FIGURE 2.23 Cylinder Cam
(Source: Courtesy of SARGENT® Manufacturing Company)
FIGURE 2.24 Cylinder Collar
(Source: Courtesy of SARGENT® Manufacturing Company)
Grades
Although cylinders are not typically referred to in grades, ANSI/BHMA A156.5 American National Stan- dard for Cylinders and Input Devices for Locks, 2010, describes grades 1, 2, and 3. The grading tests include operational, finish, and security tests. These tests include torque to rotate cylinder plug, cyl- inder body or housing tension and torque tests, cycle testing, cylinder plug pulling tests, and cylinder plug torque tests.
Housing
All of the components, including the cylinder plug, springs, and pins all come together in the housing where they work together in order to operate the cylinder.
Keying
The subjects of keying and master keying should have their own manuscript and reference guide, more suitably written by a master locksmith, one of which I am not, but several of whom I have close friend- ships. With that said, I will give a brief overview of keying in general.
Not including the various levels of security that cylinders have as options, keying can be very simple or very complicated. Cylinders can be individually keyed, also known as keyed different, or KD, or a change key. They can also be master keyed at various levels.
FIGURE 2.25 Cylinder Illustration
(Source: Courtesy of SARGENT® Manufacturing Company)
FIGURE 2.26 Mechanical Key (Source: Courtesy of SARGENT®
Manufacturing Company)
FIGURE 2.27 Mechanical Key
(Source: Courtesy of SARGENT® Manufacturing Company)
Keying is done with mathematics. There are certain calculations, depending on the number of pins in a cylinder, whether it be 5 pins or 6 pins, with or without sidebars or various levels to create the matching shear line in order to rotate the plug in the housing to operate the locking device.
Master Keying
Master keying is the art of creating a master key system, pinning, and operation of a key and cylinder.
A master key is a key that opens all or part of the locks in a system, but there can also be various levels of master keying. An example is a floor master key where the floor master only opens a respective floor, such as the third floor, while the grand master key opens all of the locksets on the first, second, and third floors. A great grand master key would open several buildings, say, in a global company or several buildings on one site like a campus. This way the CEO or any other executive requiring access to all or certain parts of a facility would only need to carry one key and it would operate no matter where he or she traveled.
Another type of master key is the janitor key, which would only open the janitor closets in a building, or an exterior master, where the key would only open all perimeter doors.
Materials
Cylinders are typically manufactured from cast, forged, or wrought extruded aluminum, brass, or bronze. Some other options available are stainless steel, iron, wrought steel, and zinc alloys.
Pin
The pins and springs are aligned in length with the key cutouts so that the shear line or multiple shear lines in a multilevel master key system can be created. Some manufacturers offer higher security cylin- ders where there are additional alignments that need to take place in addition to the main shear line, such as side bar alignment.
Plug
A key has various depth cutouts along the top of the blade that protrudes out of the bow, which is what our fingers grab onto in order to rotate the key in the cylinder. These cutouts need to align with what is known as the shear line inside of the cylinder plug so that the plug will rotate in the cylinder housing.
FIGURE 2.28 Simple Master Key System Illustration (Source: Courtesy of Rockwood® Manufacturing Company)
Side Bar
Some manufacturers offer higher-security cylinders, where there are additional alignments that need to take place in addition to the main shear line, such as side bar alignment. The cylinders are manufac- tured with bars along the sides that require the key to have grooves to accept those side bars; otherwise the key will not enter the cylinder plug at all.
Spring
The springs and pins are aligned in length with the key cutouts so that the shear line or multiple shear lines in a multilevel master key system can be created.
TYPES