Lesson 2: Tools, Locks, and Keys - Part 2Types Of Key Operated Locks
The International Association of Home Safety and Security Professionals defines a lock as “a device that incorporates a bolt, cam, shackle or switch to secure an object – such as a door, drawer or machines – to a closed, opened, locked, off, or on position, and that provides a restricted means of releasing the object from that position.” In this section we will be discussing some of the ‘usual suspects.’ The most commonly encountered key operated locks will be discussed below. Most of the key operated locks use pin and tumblers to engage with the key unless otherwise stated. Greater specificity will be given to each lock as we learn to service them in later chapters.
- Grade 1: Commercial grade locks
- Grade 2: Residential and light commercial use.
- Grade 3: Residential use
There are many different types of deadbolts and handle sets available. Each has its own purpose and it’s important to know what that is. One of the distinctions you need to make is about the grade of the lock. The grade of the lock is determined by manufacturer’s standards and refers to testing on 3 factors.
examines the amount of torque needed to retract the latch bolt with and without the key. For key-in-knobs to receive a grade, toque used may not exceed 9 lbf-in. For lever handles, torque may not exceed 28 lbf-in. For all locks, to turn the latch and retract the bolt, torque may not exceed 9 lbf-in.
examines how much turning force a lock in the locked position can withstand. For grade 1, a key-in-knob must withstand 300 lbf-in; a lever lock must withstand 450 lbf-in. For grade 2, a key-in-knob must withstand 150 lbf-in; a lever lock must withstand 225 lbf-in. For grade 3, a key-in-knob must withstand at least 120 lbf-in, and a lever lock must withstand at least 180 lbf-in.
determines how many the lock can be operated before failure. For grade 1, a lock must complete 800 000 cycles. For grade 2, a lock must complete 400 000 cycles. For grade 3, a lock must complete at least 200 000 cycles. Colloquially speaking, most locksmiths refer to grades in a tier system: knock offs, residential, commercial, and high-security. High security locks offer the maximum amount of security. These locks have commercial grade durability along with the greatest degree of access control. High security features include exclusive keyways, pick proof locking mechanisms and drill resistant hardware. Knock off locks don’t have a brand name and are often made offshore. They are made from cheap parts and materials and will not survive an attack or lengthy period of use. As a rule, locksmiths do not carry knock off grade locks in stock. When you encounter them on the job, you should suggest to your customer that they upgrade their locks.
- Passage Set:
This is your standard handle set. There is no locking mechanism. The latch bolt can be released by either handle.
- Entrance Set:
The lock is in the unlocked position unless the outside key or internal lever locks the outside knob.
- Privacy Function:
you see this most often on bedroom and bathroom doors. On one side is the thumb turn which engages the locking mechanism, on the other side is a small hole. You can insert a poking device into the hole to disengage the lock.
- Storeroom Function:
You see this most often in storage rooms and lockers. The lock handle is always in the locked position. The latch can be retracted by a key on the outside.