What are concealed hinges?
We’ve put together this guide to introduce you to concealed hinges, which are sometimes called invisible door hinges or hidden hinges. Concealed hinges are designed to be out of sight when a door or cabinet is closed. Unlike traditional hinges that are visible on the outside, concealed hinges are mounted inside the cabinet or door frame, providing a minimalist look and feel. In this guide, we’ll cover:
Basic parts of a concealed hinge
Benefits of using concealed hinges
What are the different types of concealed hinges?
How concealed hinges work
There’s no one way in how a concealed hinge works – it depends on the hinge and the door. Some industrial heavy-duty hinges require you to screw the hinge onto the door frame and then weld the other part onto the door. These weld-on concealed hinges are typically used for high-security enclosures and heavy-duty doors. Other concealed hinges simply screw on.
You’ll also come across concealed hinges designed for a specific direction: left-hand or right-hand. Sometimes, both are possible. For example, a right-hand concealed hinge goes on the inside right of the door as you look at it.
Concealed installation: Concealed hinges are installed within the door and frame, remaining out of sight when the door is closed. This installation involves securing one part of the hinge to the door and the other to the frame, with the hinge components typically embedded into the materials.
Multiple pivot points: They often use multiple pivot points or a sophisticated kinematic mechanism for a smooth opening and closing of the door. The multi-link system ensures precise and controlled movement.
Basic parts of a concealed hinge
There are so many different concealed hinges, but for our purposes, let’s consider the type you might use for junction boxes. Concealed hinges facilitate quick access for repairs or maintenance. Constructed with multiple engineered parts, typically in steel or stainless steel, they offer exceptional durability.
Key components:
● Quick release pin: A sturdy steel pin with a user-friendly design for easy door removal.
● Box leaf: The hinge base attached to the cabinet or box frame using bolts.
● Hex bolts: Securely fastens the box leaf to the box itself.
● Lid leaf: The hinge portion attached to the door, connected to the hinge body via a traditional knuckle joint. The lid leaf rotates around the quick release pin when the box is opened.
Benefits of using concealed hinges
For industrial applications, there are several reasons to use a hidden hinge. Here are the main advantages:
● Appearance
Concealed hinges are used to improve appearance, and that’s no different for industrial uses. They contribute to a minimalist design, free from visible hardware that might detract from the overall aesthetic of the application..
● Security
Concealed hinges prevent tampering from the outside. This is why they’re ideal as enclosure hinges. used in the interior of outdoor telecom equipment cabinets and other enclosures. They’re perfect for preventing tampering with the door.
● Adjustable
Some designs are adjustable to allow you to line up doors for easy and smooth opening and closing: up and down, left and right, in and out. This lets you fine-tune the fit and function of the door.
You should know about all hinge types before making any decision. We urge you to learn more in our guide, Types of hinges and where to use them.
What are the different types of concealed hinges?
Cabinets, entry and interior doors, corner units and other furniture are just some applications that use a concealed hinge. Styles vary, from those suitable for machine-covers and metal enclosures to heavy-duty applications.
Let’s look at some of the different types.
Screw/weld-on concealed hinges
These concealed hinges are available in steel and stainless steel, offering dual installation methods:
● Screw-on: Provides holes for screws. Requires threaded studs welded into the door and box.
● This method is straightforward and convenient for installations where welding is not feasible.
● Weld-on: The hinge also has surfaces that can be welded, providing a strong and permanent bond. This method is ideal for metal enclosures.
To find out other types of industrial heavy-duty hinges, check out our expert guide, The advantages of heavy-duty hinges.
Screw-on concealed hinges
The hinge shown here is 30% glass-filled nylon, ideal for applications such as lightweight panels and vehicle tool boxes. With a hinge rotation of 90°, it’s easily and quickly installed with screws.
Metal types are popular as enclosure hinges. They also work well for machine covers, such as those needed for industrial generators. The removable pin allows easy access when lifting the door from the frame. Available in different styles in steel, stainless steel, and zinc alloy with rotational angles of 90°, 110° and 180°. Ideal as both light and industrial heavy-duty hinges.
Spring-loaded, removable concealed hinges
Available in a variety of styles in steel and stainless steel, these are ideal for internally mounted doors and access doors on machinery.
This concealed hinge contains a spring to keep the pin in place. The spring also makes door removal a cinch.
This spring-loaded concealed hinge is a type of corner hinge for internally mounted doors. It’s also a steel, copper-plated weld-on concealed hinge. It can be used as a pair or with a hinge pin. The rotational angle is 110°.
View our range of spring-loaded concealed hinges
Just a note – to make your job easier, visualize the concealed hinge's fit and function within your design. Simply download CADs.
How many concealed hinges per door?
You have to consider several factors. The number of concealed hinges you use will depend on the weight, height and width of the door.
While manufacturers will tell you how many of your chosen hinges to use, these are the general rules to follow:
Door height and weight
A 40 in. (101.6 cm) door in height usually needs two hinges. Another 20 in. (50.8 cm) to the door height requires a third hinge, regardless of your door’s weight.
| Door height |
Number of hinges needed |
| 60 in. (152.4 cm) | 3 |
| 80 in. (203.2 cm) | 4 |
| 100 in. (254 cm) | 5 |
A door weighing 15 lbs. (6.8kg) requires two hinges. For every 14.9 lb (6.78 kgs) added, you’ll need to add another hinge. This is regardless of the door’s height.
Note: if the door’s height and weight require a different number of hinges, always use the larger number.
What about the sizes of your hinge? Our experts have put together a helpful guide for you. Find out how to determine the size you need in How to size hinges.
Materials
The ideal hinge material depends on several factors, including your intended application (residential, commercial, or industrial), load-bearing requirements, environmental conditions, and budget. The common materials to consider include:
● Zinc alloy
The concealed hinges are cost-effective, offering reasonable durability when treated properly. Keep in mind that they generally have lower strength than other materials.
● Steel
Steel is known for its exceptional strength and durability, making the material perfect for industrial heavy-duty hinges.
● Stainless steel
Stainless steel hinges excel in strength, durability, and resistance to corrosion, making them ideal for harsh environments. They have a long lifespan and an attractive appearance, though they are typically more expensive.
30% Glass-filled nylon
These concealed hinges offer a unique combination of strength and lightweight properties. They’re highly resistant to wear and corrosion, making them suitable for environments where metal hinges might not be ideal. These hinges are also cost-effective and provide good durability.
Download free CADs and try before you buy
Free CADs are available for most solutions, which you can download. In many cases, you can also request free samples to make sure you’ve chosen exactly what you need (limitations apply).
If you’re not quite sure which solution will work best for your application, our experts are always happy to advise you. Whatever your requirements, you can depend on fast dispatch. Request your free samples or download free CADs now.
Questions?
Email us at sales@essentracomponents.com or speak to one of our experts for further information on the ideal solution for your application 800-847-0486.