To enhance the corrosion resistance of pipe fittings, factories typically apply galvanization to these fittings.

Galvanizing generally falls into two categories: hot-dip galvanizing and electro-galvanizing.

Regarding the sizes and forms of galvanized pipe fittings, these include: bushings, elbows, couplings, caps, tees, unions, and hex plugs.

Galvanized malleable iron pipe fittings are commonly used in systems for transporting fuels, water, gas, and other fluids in industries such as chemicals, waste incineration, and semiconductors. These fittings are pipes with substantial wall thickness, coated with a protective zinc layer that shields against rust, corrosion, and mineral accumulation while withstanding humid conditions. Female threads are located inside the fitting, while male threads are on the outside, which screw into the female threads. The threaded connections used include NPT (American Standard Threads) or BSPT (British Standard Pipe Taper), sealed with PTFE tape. These galvanized pipe fittings come in a wide range of sizes and shapes.

You can find galvanized elbows in 45-degree and 90-degree angles, designed to redirect the flow of water. The fitting connects directly to the pipe. Additionally, 45-degree and 90-degree street elbows are available. Unlike standard elbows, street elbows attach to the galvanized fitting instead of the pipe, changing the pipe’s direction.

Galvanized couplings are designed to join two pipes. These couplings fit tightly together to prevent leaks.

Galvanized caps are used to seal the ends of galvanized pipes securely, ensuring an airtight closure.

Galvanized tee fittings are ideal for merging or splitting fluid flows. These fittings are particularly useful when connecting pipes of different diameters or when there is a need to redirect pipes in various directions.

Unions, often confused with couplings, are used to connect two pipes. The key difference is that unions offer a quicker and easier way to disconnect a pipe for maintenance purposes.

Hot-dip galvanizing involves a reaction between molten metal and the iron base to form an alloy layer, ensuring a solid bond between the base and the coating. The process begins with degreasing the fittings, followed by pickling to remove iron oxide from the steel surface. The fittings are then immersed in a bath of preheated molten zinc, which forms a protective zinc layer on the surface of the fittings. This process results in strong corrosion resistance as the alloy layer integrates seamlessly with the pure zinc layer and the pipe fitting’s base.

Cold galvanizing, also known as electro-galvanizing, involves applying a thin zinc layer (10-50g/m²) to the fittings via an electrolysis process. The zinc layer adheres less firmly to the base of the fittings, making it prone to peeling and offering less corrosion resistance compared to hot-dip galvanizing. The electro-galvanizing process starts with degreasing and pickling the fittings, followed by immersion in a zinc salt solution. The fittings are connected to the negative pole of an electrolysis device, with a zinc plate at the positive pole. When electricity is applied, zinc ions move toward the negative pole and deposit on the fittings.

While it may be difficult to distinguish the two types of galvanized fittings from their appearance alone, their differences are significant.

Hot-dip galvanized pipe fittings offer benefits such as an even coating, strong adhesion, and an extended lifespan. The zinc layer in hot-dip galvanizing is many times thicker than that of electro-galvanizing, resulting in far superior corrosion resistance.

Electro-galvanized pipe fittings are cost-effective and have a polished, bright appearance but offer inferior corrosion protection.

Jizhong Casting Company has made a significant advancement in electro-galvanizing, producing a surface finish that nearly matches the performance of hot-dip galvanizing. This technology has been granted a Chinese design patent. The following image showcases both hot-dip galvanized and electro-galvanized pipe fittings produced by Jizhong Casting Company.

Hot-dip galvanizing is well-suited for outdoor pipe fittings, such as those used in sports facilities, power towers, bridges, and large fasteners that require long-term corrosion resistance. On the other hand, electro-galvanizing is typically used for smaller fasteners and indoor pipes that need rust prevention.

Founded in 1990, Jizhong is a top manufacturer and supplier of galvanized pipe fittings. The company currently employs over 150 individuals, with more than 50 technical engineers, and has distributors in over 100 countries worldwide. Jizhong is dedicated to making the world a safer place by providing high-quality galvanized pipe fittings to homes and buildings.

*Standard: EN10242 / ANSI / ASME B16.3 / DIN2950 / ISO 49 / NBR6943 / IS1879 / BS EN10242

*Threaded Standard: EN 10226 / ASME B.1.20.1 / DIN2999 / IS07-1 / IS0228 / IS554 / BS EN 10226

Galvanized fittings feature a minimum coating thickness of 86µm or an average coating weight of 610g/m²

You’ve found the right place. Jizhong is a leading manufacturer of malleable cast iron and galvanized pipe fittings, offering premium products at competitive prices. We supply high-quality galvanized pipe fittings to North America, Europe, and the Middle East. Our product range includes elbows, nipples, tees, nuts, caps, crosses, flanges, and more. For more details, visit our product pages or reach out to us.