Which fitting is typically used to connect two sections of pipe directly?

The fitting that is typically used to connect two sections of pipe directly is a coupling. Couplings are designed specifically for this purpose, allowing for a secure connection between two pipes and ensuring continuity in the flow of fluids or gases. They come in various sizes and materials to accommodate different types of piping systems.

In contrast, other fittings serve different functions. An elbow is used to change the direction of the pipe run, creating a bend, while a nipple is a short length of pipe with threads on both ends, primarily used to connect two other fittings or pipes together, often in more specific configurations. A reducer, on the other hand, is utilized when transitioning between two different pipe sizes, allowing for a reduction in diameter. Thus, while all these fittings play important roles in plumbing and piping systems, the coupling is the appropriate choice for directly connecting two pipe sections.