Steam Traps Flashcards
What’s a steam trap?
Self contained valve which drains condensate from steam system
Why do we use steam traps ?
Prevent water hammer
What’s water hammer ?
A sudden intense pressure surge due to wave in a fluid or vapor system
3 types of steam traps we use at PVGS?
Mechanical, thermostatic, thermodynamic
Two types of mechanical traps ?
Float lever,free float
How does an inverted bucket trap work ?
A upside bucket gets lowered/raised which closes/opens a valve
What type of thermostatic steam trap do we use at PVGS?
Balanced pressure
How does a balanced pressure trap work ?
bellows with liquid that pressurizes/ depressurizes in response to temp. Which open/closes trap
What type of operations are balanced pressure traps mainly used for ?
System start ups where large volumes of purging are required
What type of thermodynamic steam trap do we use at PVGS ?
Disc trap
How does a disc trap work ?
When steam enters it applies for pressure on top of disc due to surface area which seats the valve. When condensate enters it cools steam and opens the disc to let condensate pass
How are steam traps identified on P&IDS?
A box with several valve numbers inside it
How do you find details of the steam trap ?
Mechanical legend P&ID using trap detail
What can be done if trap isn’t operating properly ?
Operate manual bypass valve to drain condensate
What are Critical steam traps ?
If removed from service needs alternate way of draining/depressurization of the affected area of piping
