A cross, also known as a four-way fitting, is a type of pipe fitting that allows for the connection of four pipes at right angles, forming a cross shape. It is commonly used in plumbing and piping systems to facilitate the distribution of fluids or gases.

The main purpose of a cross is to provide a central point for branching out multiple pipelines in different directions. It allows for the efficient distribution of flow to various sections of the system, enabling multiple supply or distribution lines to be connected. This makes it particularly useful in applications where there is a need for fluid or gas transfer to different locations simultaneously.

Some advantages of using a cross include:

1. Versatility: A cross fitting can accommodate four pipes, offering flexibility in system design and layout. It allows for connections in all four directions, facilitating complex piping arrangements.

2. Equal distribution: The design of a cross ensures an even distribution of fluid or gas flow among the four connected pipes. This helps maintain balanced pressure and flow rates throughout the system.

3. Simplified installation: By using a cross, multiple branches can be connected at a single point, reducing the number of fittings and connectors required. This simplifies the installation process, saves time, and reduces the risk of leaks or failures.

4. Compatibility: Cross fittings are available in various materials such as brass, stainless steel, PVC, and copper, making them suitable for different applications and environments. They are also manufactured in different sizes, allowing for compatibility with various pipe dimensions.

Cross fittings find applications in a wide range of industries, including residential, commercial, and industrial sectors. They are commonly used in plumbing systems, irrigation systems, HVAC (heating, ventilation, and air conditioning) systems, and process piping systems. Crosses are particularly beneficial in systems where multiple supply lines or distribution lines need to be connected, ensuring efficient and reliable fluid or gas transfer.