The book "Dust control Handbook for mine" has mentioned 4 equipment for discharging dust from baghouse.

However I couldn't find any information or picture from 2 of them as below:

1- Tilt Valves

Tilt valves are similar to double dump valves and are normally used in pairs....

2- Vacuum or Dribble Valves

A vacuum valve basically consists of a soft gum rubber tube mounted in a steel housing....

would you please help me to understand how these valves work.

Thanks in advance ■