Your Reliability Engineering Professional Development Site
When a control valve or manual valve is shut fast in a full pipeline of moving liquid, the liquid comes to a sudden stop. If the pipe suddenly starts banging and thrashing about you can be sure a water hammer was created. [Read more…]
This true story could have been a lot worse. A NB100 (4”) flanged plug valve was removed from a 98% sulphuric acid tank nozzle and returned to the supplier. When the valve was opened for inspection at the supplier’s workshop acid was sprayed over the repairman’s legs.
If 98% sulphuric acid lands on skin it immediately boils out the moisture in the skin and burns it. A review of the incident was conducted to learn from the accident and to put corrective measures into place. [Read more…]
What readers will learn in this article.
Valves can be used to both isolate and regulate liquid and gas flow.
Valve used for isolation duties must provide secure, tight shut-off. Consideration must be given to the nature of the process chemical, the quality of sealing and the impact of outside environmental occurrences.
Keywords: bubble tight, design pressure, leakage rate, fire rated, differential pressure. [Read more…]
