Waterproof Enclosure Design in Product Manufacturing

How is Waterproof Grade Divided?

The rating system is a term that qualifies many electronic products based on their ruggedness. As related to this material, it is ideal to divide them based on their waterproof ability. Without the rating system, using ruggedness and waterproof properties is a simple marketing term. For example, it is impossible to know the extent to which a product can withstand water when submerged. However, with a rating system, you can know about the extent of such properties. The two popular rating systems that we will discuss are the IP and NEMA rating systems.

Waterproof Enclosure Design in Product Manufacturing

IP Rating System

People using electronic products would be familiar with the IP rating system. It is highly possible to have seen an inscription on their device with IPxx. This inscription is what manufacturers use to judge if an electronic product's water seal design is effective and the extent of its effectiveness.

IP rating stands for Ingress Protection (IP) ratings, and from the above example, it has two letters, “IP” and two digits, e.g., IP67. The first number shows protection against physical objects such as dust and dirt. The second number shows protection against a liquid environment.

The higher the IP rating, the better the sealing design. For example, a product with an IP32 rating has lesser protection when compared to the same product with an IP67 rating.

NEMA Rating System

NEMA is an acronym for the National Electrical Manufacturer Association, and its rating system also shows how protected a product is. Unlike the IP system of rating, the NEMA rating system is mainly for industrial products. The IP rating system estimates the protection a product has from water and physical parameters such as water and dust. However, the NEMA rating system goes a little further as it deals with exposure to parameters such as ice, corrosives, and oil.

Before using the NEMA rating system, you should know the following:

• Whether the product is an indoor or outdoor one
• Element exposure
• If it will be hosed down
• Whether there is a chance of exposure to corrosive agents, oil, and coolant

NEMA rating system can be in terms of indoor and outdoor use. For indoor use, we have a rating from 1–13, which shows an increase in the degree of protection from dust and electrical shock, i.e., the higher you go, the better the protection. For outdoor use, we have NEMA 3, 3R, and 3S. NEMA 4 is used for products used under conditions such as high-pressure water.

Waterproof Enclosure Seal Design

Using a water seal design comes with understanding the various ways of getting things done. There below are a few ways you can make a watertight seal.

O-rings

O-rings are important in water seal design and also for repairing things. They are very popular, which shows that they are widely used. They have one shape but come in different sizes. An O-ring has two numbers that show its inside diameter and outside diameter. O-rings are easy to install, and they come in two types: Static O-rings and Dynamic O-rings.

· Static O-rings

If your water seal design is for circular products, using a static O-ring is ideal. Static O-rings are seals where the mating gland parts do not move relative to one another. Therefore, there is no movement on the sealing surface.

· Dynamic

Dynamic O-rings, unlike the Static types, move concerning their mating gland parts. Therefore, the material needs more lubrication. The materials also must be tougher than the materials used to manufacture static O-rings.

• Major Differences between Static and Dynamic O-rings

Understanding the use of static or dynamic seal rings comes with knowing their differences. Below are the major differences that help you make a watertight seal when using the two seals.

• Because dynamic O-ring moves constantly, the materials used in the manufacture must be tougher.
• Dynamic O-ring gland must have a surface finish that does not have abrasive properties. If they have an abrasive surface, it can lead to the development of wear and tear. This is, however, irrelevant in static O-ring since it doesn’t move.
• Dynamic O-rings need more maintenance than static O-rings.
• Even though the two seals need lubrication, Dynamic O-rings should be more lubricated.

Gasket

A gasket as a sealant is an adhesive glue, paste, or spray used in holding mechanical joints together. It can be used together with or without other types of sealants, and with or without, it reduces the tendency of mechanical breakdown when the parts rub together.

A gasket is ideal for complex face-to-face seals involving multiple cavities. This is one area they excel more than O-rings. However, you have to consider factors such as compression, thickness, and tolerances of the joints to be mated to use them. Generally, gaskets are custom. Therefore, you don’t have to worry about constant calculations.

Button

Buttons are used in directional pads, triggers, and panel switches, and they are ideal sealants for those who worry about interfacing. They are also cheap and easy.

Depending on what they are to be used for, buttons can be made of different materials. For example, for low-pressure waterproof button design, molded rubber buttons are used as a sealant. However, for a heavy-duty waterproof button design, the button can be made of harder materials.

There are many waterproof button designs, and they are usually worked with dynamic O-rings. However, it would be best to use them with caution since many seals can lead to seal failure.

Material Selection

Knowing and selecting the right materials comes with understanding the necessary factors that you should consider before selecting the right materials. This will be in two sections. One will be about the factors that aid selection, while the other will be about the common materials you can use.

Factors to Consider in Material Selection

• Stage of Development

The stage of development determines the material you are using. For example, during the prototype development stage, a low-level material that is cheap is used to get the right fit, function, and aesthetics. Therefore, you won’t worry about the water seal’s effectiveness, and you will get to know about the error easily. You can then use the original materials when done.

• Use and Design Guide

The design guide you use in manufacturing the product decides the type of materials you choose. For example, high-pressure product enclosure design requires CNC machining to control the surface quality.

• Durability and Environment

Durability has a relationship with the environment in which the material will be used. For environments that require high durability, metallic waterproof enclosure materials should be used. Material selection also depends on whether the materials will be used outdoors or indoor.