Skin fittings

What are skin fittings? 

A skin fitting is a fitting or device that is installed in the hull of a boat or ship. This allows pipes, cables or other mechanisms to pass through from one side of the hull to the other while maintaining watertightness. Skin fittings are typically made of materials such as bronze, brass, stainless steel or plastic, which can resist corrosion and the constant pressure of water. 

Multi-purpose skin fittings 

Skin fittings are designed to ensure a tight and safe passage for various systems through the ship's hull. This makes them essential for the function and safety of the ship. The areas of application include:   

• Water pipes: Used to carry water in and out of the ship, for example, for engine cooling systems or toilet systems.  

• Cable entry: Enables the safe passage of electrical cables and hydraulic hoses through the hull, eliminating the risk of water ingress.  

• Bilge pumps: Skin fittings are also used as outlets for bilge pumps, which pump water out of the lower points of the boat. 

These penetrations can be made during the construction and maintenance of the boat, or when the boat requires a repair or upgrade because the old skin fittings are worn out.   

Find skin fittings in good materials at Biltema 

At Biltema, you'll find a wide range of skin fittings in a variety of sizes and materials, so you can find the right one for your needs. Our range includes skin fittings made of zinc-free brass, glass fibre-reinforced PP plastic with an outer ring of acid-resistant stainless steel, and PP plastic. 

When selecting the correct size, it's essential to measure the area where the grommet will be installed accurately. And the materials offer different advantages:   

• Zinc-free brass is durable and resistant to corrosion and galvanic corrosion.   

• Glass fibre-reinforced PP plastic with acid-resistant stainless steel for enhanced strength and durability.  

• Pure PP plastic is a lighter and more cost-effective alternative to brass, for example, and it is safer from corrosion. 

The choice of material depends on your specific needs and the environment where the skin fittings will be used. 

Avoid galvanic corrosion 

Galvanic corrosion is a form of corrosion that occurs when two different metals or alloys come into electrical contact with each other in an electrically conductive liquid, typically salt water. This creates an electrochemical cell where the less noble metal (often zinc, aluminium or iron) begins to corrode while the more noble metal (often stainless steel and copper) is protected. 

To protect against galvanic corrosion, you can use the methods below:    

• Insulating the metals from each other: Use insulating materials between dissimilar metals to prevent electrical contact.  

• Correct material selection: Choose materials that are electrochemically compatible and can reduce the risk of galvanic corrosion. For example, stainless steel and bronze should never be mixed. 

Galvanic corrosion is an important consideration in the design and maintenance of many types of structures, especially those exposed to aggressive environments like seawater. By understanding and managing the electrochemical properties of metal use, the lifespan of these structures can be significantly extended. 

We have more than skin fittings at Biltema 

In addition to a wide range of skin fittings, Biltema also offers a wide range of other products in the boat plumbing category that are essential for both maintaining and upgrading your boat. Among these products, you'll find our selection of bottom plugs, which are essential to ensure that water from rain and waves that has entered the boat can be released once it's pulled ashore.   
Our range also includes boat toilets, which are a necessity on longer sailing trips where comfort and hygiene are important. These toilets are designed to be efficient and easy to install, making them an excellent choice for boaters looking to upgrade or replace their existing boat toilet. 
 
Perhaps you're also looking for our range of plumbing hoses? These are essential for the safe and efficient management of water and other liquids on board. Naturally, the hoses are made from materials that can withstand the harsh marine environment and are available in various sizes and materials to match specific needs and applications.   

Whether it's upgrading your boat's water system or installing new plumbing elements, Biltema has the necessary products to help you complete your project. 

FAQ

Which material is best for skin fittings?

The best material for skin fittings depends on both the application and the boat's construction; however, bronze is often considered one of the best choices due to its exceptional corrosion resistance and strength. It's essential to select a material that's compatible with the boat's hull material to prevent galvanic corrosion.

How long do skin fittings last?

Skin fittings can vary in lifespan. On average, a skin fitting can last between 10 and 20 years. However, it is important to regularly inspect and maintain them to ensure the safety and integrity of the ship. Consider replacement if there are signs of wear or damage.

Can I replace my skin fittings myself?

You can replace your skin fittings yourself, but it requires the right knowledge and tools. It's essential to select the appropriate materials and ensure the installation is watertight to prevent leaks. If you are unsure, it is recommended to consult a professional to ensure a safe installation.