- Steam Theory
- 1. Basics of Steam
- 2. Steam Heating
- 3. Basics of Steam Traps
- 4. Steam Trap Selection
- Steam Trap Selection: How Application Affects Selection
- Steam Trap Selection: Understanding Specifications
- Steam Trap Selection: Safety Factor and Life Cycle Cost
- Traps and Orifices Part 1
- Traps and Orifices Part 2
- Casting vs. Forging
- Don't Get Steamed : Selecting Steam Trap Design
- Understanding Steam Traps
- 5. Steam Trap Problems
- 6. Steam Trap Management
- 7. Water Hammer
- 8. Steam Quality
- 9. Steam Distribution
- 10. Condensate Recovery
- Introduction to Condensate Recovery
- Returning Condensate and When to Use Condensate Pumps
- Condensate Recovery: Vented vs. Pressurized Systems
- Condensate Recovery Piping
- What is Stall?
- Methods of Preventing Stall
- Cavitation in Condensate Pumps
- Steam Heat Exchangers are Underworked and Over-Surfaced
- Stop Knocking Your Condensate Return
- 11. Energy Efficiency
- 12. Compressed Air / Gas
- 13. Other Valves
What is Water Hammer/ Steam Hammer?
Have you ever heard a loud 'BANG' or hammer-like sound after quickly turning on or off a water faucet? This is the sound of water hammer in the water piping system. In a factory, a pump starting up operation or shutting down, or an air vent suddenly closing are examples of when this might occur.
In addition to water transport piping systems, water hammer also occurs in steam and condensate recovery (i.e. water circulation) systems. This series of articles will focus on water hammer in these latter two systems. Note that as steam is involved, this type of water hammer is also sometimes referred to as 'steam hammer'.
The Dangers of Water Hammer
When steam is first supplied to steam distribution piping or steam-using equipment, a metallic and repetitive 'bang, bang, bang', or even sometimes a violent 'boom' accompanied by vibration may be heard. Most steam users will probably have experienced one of these at some time.
When water hammer occurs, a momentary abrupt pressure change of over 10 MPa may occur inside the piping.
This impact can severely jar piping, equipment or machinery housing, possibly resulting in damage not only to gaskets in junctions, but also to valve flanges or the valves themselves.
As soon as something like this, such as a valve, becomes damaged, large quantities of steam or hot condensate begin blowing out, which could lead to a serious accident. There have even been reports of deaths occurring as the result of water hammer. In spite of this, there is remarkably little research or literature devoted to its causes and prevention, and many steam users find themselves at a loss with how to cope with the issue.
Places Water Hammer (Steam Hammer) Occurs, by Type
|Why Bad Things Happen to Good Steam Equipment||Water Hammer: The Mechanism|