A security hinge is a protective feature that prevents potential crime, such as theft or vandalism, by making it difficult to remove a door by tampering with the hinges. They may be used on exterior doors for security, as well as in secured facilities where containment within a building is necessary. In addition to providing protection from threats like vandalism, most also have a fire rating which indicates how long they should remain intact in high heat conditions. Hardware and home supply stores sell security hinges and accessories that can be used to convert existing hinges to make them safer.

When selecting security hinges, it is important to think about weight and fire resistance ratings. The security hinge should be heavy enough to handle the weight of the door as well as anticipated uses. Secured doors should ideally be heavy to make them difficult to break down and add fire resistance, and hinges may provide information on how much weight they can comfortably bear. Fire resistance ratings offer an estimate on how long hinges will hold up in a fire, and a fire department can provide specific advice on the best ratings for a given structure.

Spring hinge is a hinge containing one or more springs; when a door is opened, the hinge returns it to the open position automatically; may act in one direction only, or in both directions (as on a swinging door).

Spring hinges keep a door or hatch in a certain position, whether open or closed. Although you can open the door, the spring will settle it back into place when you let go. You can find spring hinges in some cabinet doors, jewellery boxes and items that have a latch or lock. If you already have a traditional pin hinge, you can make your own spring hinge for any of your homemade projects.

Spring hinges are on doors that require automatically closing capabilities without the use of a door closer. There is a spring inside the barrel that adjusts to provide the closing action. Some house doors have these types of hinges and are recognisable by the two holes on the side of the barrel where a hinge pin sits on a standard hinge. To remove spring hinges from a door requires releasing the spring tension inside the barrel. The spring hinge removes in one piece.

To fit a double action spring hinge, you will first put the hinge on the door where it is desired. Secondly, mortise the hinge space of the door using the adjustment ring at the top and install the hinge. The hinge uses one direction as the outside part and the other as the inside part so that the door swings in both directions.

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