How are grooved pipe couplings held together?

Grooved pipe couplings are held together using a bolted tri-split metal collar, which is a design that enhances the integrity and strength of the connection. This type of coupling features a ring that secures the pipes in place by wrapping around their grooves, ensuring a firm grip. The tri-split design allows for easy installation and disassembly, which is particularly advantageous in situations where adjustments or repairs are needed.

The use of a metal collar also provides durability and resistance to high pressure, making it a reliable choice in various piping systems. The bolted connection ensures that the pipes remain securely coupled under operational conditions, minimizing the risk of leaks or separation.

The other options, such as welding, soldering, or using a plastic collar, do not accurately reflect the method used in grooved pipe couplings. Welding and soldering involve the fusion of materials, which is a different approach altogether, while a bolted plastic collar would lack the necessary strength and durability required in many industrial applications.