New Mexico Pipe Fitter Journeyman (JPF) Practice Exam

What is one type of bonnet assembly in valves?

1. Welded

2. Rotatable

3. Flange-less

4. Non-removable

The correct answer is: Welded

A welded bonnet assembly is a method for securing the bonnet to the valve body by welding. This type of assembly is commonly used in applications requiring a high level of pressure containment and where leakage needs to be minimized. Because the bonnet is welded, it creates a strong, permanent connection, which enhances the structural integrity of the valve and prevents any loosening that can occur with threaded or bolted connections. Welded bonnets are often utilized in high-pressure and temperature applications, where it is crucial to maintain the seal and ensure that the valve operates reliably over time. This assembly type is particularly beneficial in process industries, where even minor leaks can lead to significant safety hazards or production losses. While other bonnet types like non-removable, rotatable, and flange-less have specific applications and advantages, a welded bonnet focuses primarily on ensuring a secure, leak-proof design suitable for demanding working conditions.