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Types of Padlocks

Quick Tips #333

Padlock Basics

Padlocks are simple devices comprised of three basic components: the shackle, body and locking mechanism. Shackles are often available in varying lengths and diameters to fit a variety of locking needs.

Shackle: The loop of metal that opens up to lock a device

The solid part of the padlock that contains the locking mechanism

Locking mechanism/cylinder:
Locks usually have a keyway where the key is inserted, or they may use a type of rotary mechanism or dial


Types of Padlock Styles

Padlocks are used in virtually every business, organization and home. In order to fill the needs of these different groups, a wide variety of options and styles have been developed. The most popular types of padlocks are the following:

Laminated: The body of a laminated padlock consists of multiple pieces of metal stacked on top of each other to form a tough, tamper-resistant lock.

Lockout padlocks: Padlocks designed specifically for use in lockout programs typically have a provision on the lock to write the users name and often come with only one key to limit access to the lock.

Weather resistant
: Weather-resistant locks either have a shroud to protect the lock from the elements or are constructed from weather-resistant materials such as stainless steel. Although regular locks will work outside for a period of time, they tend to rust or corrode over time to a point where they can no longer be opened with the key or combination sequence.

A combination lock uses a rotary dial or series of buttons to unlock the device rather than a conventional key.

Combination with key control:
A combination lock with key control can be opened with a key or a combination. This type of lock is typically used in schools and locker rooms. The control key is capable of opening all the combination locks in that set.

Guarded/shrouded/shielded padlocks:
A guarded or shrouded padlock has solid metal guards that protect and surround the shackle on both sides, leaving only the top of the shackle exposed. The guards make it nearly impossible to cut the shackle with a bolt-cutter.

High security:
A high-security lock typically has one or more of the following options to increase its level of protection:

  1. Hardened steel shackle
  2. Shrouded shackle
  3. Pick-resistant key cylinder
  4. Reinforced locking mechanism to resist prying

Keying Options

For most applications, the typical padlock that comes with two keys works well. However, there are many applications where different keying options are required. The most common keying options are:

Keyed alike: All the keys open all the locks in a set of padlocks. Every key and every padlock is exactly the same. If the padlocks are not sold in a set, they typically need to be purchased at the same time in order to be keyed alike.

Keyed different: Padlocks do not have duplicate keys in that set or on that order. Each padlock has a unique key that will not open any of the other locks in that set. As with the keyed alike option, if the padlocks are not sold in a set, they need to be ordered at the same time in order for them to be specifically keyed different.

Master keyed: Padlocks are keyed different padlocks with the addition of a single master key that can open all the locks. The keys that come with the locks can only open that one lock, but an additional master key that will open all the locks in a series can be ordered separately. The master key and the master keyed padlocks must be ordered at the same time.

Rekeyable: The cylinder in rekeyable padlocks can be removed in order to (a) change the pinning or (b) replace the original cylinder with a new one, restoring security quickly and economically. This is ideal for situations where keys are lost or stolen.

Interchangeable core padlocks: These padlocks and door locks provide an instant security solution because they do not require disassembly to remove the core (cylinder). The control key fits into the padlock just like the user key, but actuates the interchangeable core retaining mechanism to allow the removal and replacement of the core (cylinder). Interchangeable cores can be used in both padlocks and door locks for facility-wide security systems.

Non-removable key: The key cannot be removed from the padlock when the lock is open. This helps prevent users from accidentally leaving the padlock in the open position.

Reserved key system: The reserved key system is not available to the general public but is a system where key blanks are cut and supplied directly through padlock distributors when requested by registered end-users. These locks are typically used by the government and some larger companies.

Materials of Padlock Construction

Padlocks are made in a variety of metals and even plastics. Some of the common materials and applications for those materials include:

Plastic: Padlocks are typically used in a light security situations where tampering isn't expected to occur.

Aluminum: Locks are generally used in light security situations. The aluminum bodies are often anodized in different colors, allowing color coding of lock systems.

Brass: Padlocks are more durable than plastic but are not as tamper-resistant as heavier steel padlocks. However, they do hold up to the elements and are often used as an inexpensive, weather-resistant light security lock.

Solid steel/case hardened steel: Padlocks are very durable, cut-resistant materials. These types of locks are typically used in higher security applications and are often chrome or zinc-plated to help resist corrosion.

Stainless steel: Like solid steel locks, these are very durable locks but stainless steel generally holds up to the elements better than solid steel.

Titanium: Extremely durable metal resists corrosion and is lightweight in comparison to solid and stainless steels. These are typically used in higher security applications.

Commonly Asked Questions

Q.   Can I get replacement keys for my padlock?
A.   If you have the key number that is stamped on the key itself, a locksmith may be able to get a replacement key for you. If you do not have the key number, it may be possible to have a locksmith make a replacement key.
Q.   Are master keyed and keyed alike locks the same?
A.   With master keyed locks, the individual keys will only open one lock but there is a separate master key that can open all the locks in a group. With keyed alike locks, every key in a group will open every lock.



(Rev. 1/2012)

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