Is it normal to rate steam boilers to full vacuum ?

[jamesbanda]

dear all,

Question as title.. is it normal to rate steam boilers to full vacuum ?

 

[athomas236]

Until 1977 I used to work for a European manufacturer of utility boilers who always provided a vacuum breaker on the steam drums until one 660MW project came along and the breaker was removed to cut costs.

During commissioning the boiler was drained for a drum internal inspection. The fitter removed the door nuts and the door was sucked into the drum along with the fitter who became wedged in the door opening. The fitter suffocated and the company paid a considerable sum as compensation.

While with this manufacturer, I used to carry out the strength calculations for steam drums and other pressure parts; a full vacuum case was not considered.

Regards,

athomas236

 

[MJCronin]

athomas,

The vacuum breaker must have been rated to withstand a very high positive pressure and no vacuum. What were the typical design conditions ?

Who makes such a device and how was it mounted on the boiler ?

-MJC