hollow metal doors 
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Hollow Metal Doors & Frames.
Wood Doors. Commercial Door Hardware.
fire rated hollow metal doors and frames

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Commercial Door Hinges

The most common hinge size for hollow metal doors and frames is the 4 1/2" x 4 1/2" square corner. Although there are many other sizes available, this is the hinge that is used unless something else is specified. Round corner hinges are usually used on wood prehung units. All wood doors that will be installed in a hollow metal frame will have the square corner hinge unless something else is specified. The first number in the size always refers to the height of the hinge while the second number always refers to the width of the hinge in an open position.

There are four basic types of hinges. Always use the door as the reference, so a half mortise hinge would be mortised into the door and surface applied to the frame as a half surface hinge would be surface applied to the door and mortised into the frame.
FULL MORTISE: The standard hinge unless something else is called for. Mortised into the door and the frame.
HALF MORTISE: This is usually used on channel iron frames with a hollow metal or wood door.
HALF SURFACE: This is sometimes used when you are installing a new door into an existing frame and the hinge locations are different.
FULL SURFACE: This is usually used on tubular steel doors with channel iron frames.

On exterior outswing doors it is a good idea to have some kind of means of security so that the hinge pin can not be removed to gain entry into the building. This is usually done with a non removable pin (NRP) hinge. This hinge has a set screw in the barrel that is only accessible when the door is in the open position. The set screw is tightened down against the hinge pin after installation so that the pin can not be removed once the door is closed.

On fire rated doors and frames, you have to use steel or stainless steel ball bearing hinges. Brass and bronze hinges will melt under extreme heat causing the door to fall out of the frame.

Spring hinges will close the door automatically after it has been opened like a door closer but there is no "sweep" and "latch" control that you find on closers. The only adjustment is how fast the door will close.

Double acting hinges will allow the door to open in and out. This is used when people will be exiting and entering often out of the same door. A good example is in a restaurant into the kitchen.

We keep a full line of hinges in stock in all of the applications mentioned above as well as many different finishes. We also have other types of hinges available such as swing clear, pivot, continuous, concealed, and many others.

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