DB&B Valve Verification

Question 1

What two types of DB&B valves are covered?

Answer 1

A 2-way and a 4-way.

Question 2

What two types of 2-way DB&B valves are there?

Answer 2

The plug and the expanding gate.

Question 3

What type of DB&B valve is a 4-way?

Answer 3

A DB&B plug type valve.

Question 4

What is the proper way to check whether a DB&B valve has a good seal?

Answer 4

Crack the bleed valve while the DB&B valve is still open. Then close the DB&B valve to see if the bleed valve stops flowing. If it doesn’t the valve may be leaking. Ensure that the check valve isn’t leaking by by either closing the check valve or tapping it to clear any trash.

Question 5

What should be connected to the bleed valve and why is it there?

Answer 5

A gooseneck, so that the bleed valve doesn’t drain the valve cavity and indicate a false leak.

Question 6

What two conditions (at the bleed valve) can falsely indicate a leak in a valve.

Answer 6

Thermal expansion over time, and draining the cavity because there isn’t a gooseneck installed on the drain valve.