I have often seen that personnel in labs and R & D setups do not understand the hazards of a pressure vessel. Many times, pilot plants are built by buying equipment from the second hand market. Not having the specifications / data sheet for the vessel is dangerous. One such fatal incident in a NASA lab highlights the following:
"Vessel at least 33 years old
• Unknown prior service, no nameplate, no drawings
• No pressure or temperature rating information
• Most welds on hold down bolts were cracked before being put into this service
.Vessel design inappropriate for intended service
– Vacuum vessel put into service as a pressure vessel
• Vessel not pressure checked prior to full use
– And no restricted access during initial pressurization
• Critical welds on hold down bolts not inspected after 33+ years of existence
– Were not considered critical for a negative pressure (vacuum) application
• Bolt welds were cracked and cracks exhibited corrosion prior to this use
• Vessel failed (chamber lid separated from chamber body) when all hold down bolt welds broke simultaneously".
Read about the incident in this link.
"Vessel at least 33 years old
• Unknown prior service, no nameplate, no drawings
• No pressure or temperature rating information
• Most welds on hold down bolts were cracked before being put into this service
.Vessel design inappropriate for intended service
– Vacuum vessel put into service as a pressure vessel
• Vessel not pressure checked prior to full use
– And no restricted access during initial pressurization
• Critical welds on hold down bolts not inspected after 33+ years of existence
– Were not considered critical for a negative pressure (vacuum) application
• Bolt welds were cracked and cracks exhibited corrosion prior to this use
• Vessel failed (chamber lid separated from chamber body) when all hold down bolt welds broke simultaneously".
Read about the incident in this link.
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