Under Deposit Corrosion of Pipe Nipple
A failed Pipe Nipple was received for failure analysis and ID deposit chemical analysis. The pipe was specified as 0.168” MWT, SA-213 304L stainless steel. The nipple was installed about 5 years ago and was used as a pressure tap for pressure indication. Nitric acid vapor flowed through the nipple at 120 psi and 500°F. The nipple thinned to failure and was plugged with deposits at the failure as shown below.