Union hook lock

Product Description

Secure Hook Bolt Engagement for Doors

A Union hook lock is a specialized locking mechanism that uses a curved, hook-shaped bolt to secure a door. Unlike a standard straight deadbolt that simply extends into a strike plate, the hook bolt rotates or extends and then hooks around a robust keep or receiver in the door frame. This design provides significantly greater resistance to forced entry, as the hook cannot be pushed back or slipped past the strike plate. Union, a trusted name in British lock manufacturing since 1840, produces hook locks for a variety of applications, including patio doors, French doors, and multi-point locking systems.

The Union hook lock is commonly found in:

• Patio Door Locks: Sliding and hinged patio doors often use hook locks as part of a multi-point system

• French Door Locks: Double doors that require secure locking at the meeting stiles

• Multi-Point Locking Systems: Where hook locks work alongside deadbolts, rollers, and latches

• Traditional Mortice Locks: Some Union mortice locks feature a hook bolt as an alternative to a straight deadbolt

  

  Union hook lock

How a Hook Lock Works

The Union hook lock operates on a simple but highly effective principle:

1. Engagement: When the lock is engaged (by key, handle, or cylinder), the hook bolt extends from the lock case

2. Rotation/Hooking: The hook bolt rotates or is shaped to curve around a specially designed keep or receiver in the door frame

3. Locking: Once hooked, the bolt cannot be forced back by inserting a tool between the door and frame

4. Anti-Slip Design: The hooked shape prevents the bolt from being slipped or manipulated

This design is particularly effective against:

• Crowbar attacks: The hook resists being pried back

• Shimming: The curved shape prevents shims from reaching the latch mechanism

• Slipping: The hook cannot be pushed out of the keep with a thin tool

“What is the difference between a hook lock and a deadbolt?”

Both are secure, but hook locks excel in applications where the door might be vulnerable to slipping or prying, such as patio doors with large glass panels.

Types of Union Hook Locks

Union produces several hook lock variants:

1. Patio Door Hook Locks
These are designed specifically for sliding patio doors. They typically feature:

• A hook bolt that engages a keep in the frame

• A cylinder or key operation

• A handle or thumb turn for interior operation

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  Union hook lock

  Often part of a multi-point locking system

2. Multi-Point Hook Locks
In multi-point systems, the Union hook lock is one component among several locking points. The hook locks engage when the door is locked, typically at the top and bottom of the door, while a central deadbolt and latch provide additional security.

3. Mortice Hook Locks
Some Union mortice locks feature a hook bolt instead of a straight deadbolt. These are used on timber doors where a traditional mortice lock is required but enhanced security is desired.

4. French Door Hook Locks
For double doors, hook locks are often used at the meeting stiles—the point where the two doors meet. The hook bolt from one door engages a keep in the other, securing both doors together.

Key Features and Benefits

• Superior Anti-Slip Security: The hooked bolt cannot be pushed back or slipped past the keep

• Durable Construction: Made from high-grade steel with corrosion-resistant finishes

• Smooth Operation: Precision engineering ensures reliable engagement and disengagement

• Versatile Application: Suitable for patio doors, French doors, and multi-point systems

• Union Quality: Backed by over 175 years of lock manufacturing expertise

• Multiple Finishes: Available in chrome, brass, satin nickel, and other finishes to match your door hardware

Technical Specifications

Applications

The Union hook lock is suitable for:

• Patio Doors: Sliding and hinged patio doors where security is paramount

• French Doors: Double doors that require secure locking at the meeting stiles

• Multi-Point Systems: As a component in a comprehensive door locking system

• Timber Entry Doors: Where a hook bolt provides enhanced security over a standard deadbolt

• Commercial Doors: Where high-security locking is required