Hi Harry I could not agree more. Even elastic will only stretch to a certain point to return to its original length one over stretched it is always "to slack".
I remember the classic Cockenzie boiler test in Scotland a number of years ago I think the plate was 8 inch thick if my memory serves me right. The boiler had been tested if I recall 8 times!! The insurance officer did not believe Lloyds etc and insisted seeing the needle on the pin. This time the boiler blew. This was put down to "brittle fracture". It had been ultrasonic and radiographically examined but no significant defects had been found. The cockenzie report is of course classic literature. Back to our little kettles, the hydraulic tests are carried out cold, the boiler is run hot. It is usual to examine a vessel before and after the test. This is to ensure that any defects which the test possibly caused or brought to notice can be found before putting the device into service. Over high test pressures can cause considerable damage when the device is put into service. A silver soldered joint is not welded and stress relieved. Who carries out a radiographic examination before and after on our little kettles??. Who has proven gauges? who uses at least two of them for the test? etc etc. I agree fully with you Harry. test to sensible pressures. unless the state requires more. Bert ------------------------- Bert & Edmunda [EMAIL PROTECTED]
