If all pipe fittings are connected by threads, is it then unnecessary to conduct flaw detection?
Thread Content
All pipe fittings are connected by threading, with no welding used. I didn’t realize this at first, so I wrote down requirements for flaw detection; but then I thought that without welding, there’s no need for flaw detection.
Threaded connections do not involve non-destructive testing. However, the possibility of thread leakage is a bit higher.
Don’t pipes connected with bolts also need welded flanges?
The flange can also be threaded: lol
If used on LNG pipelines, it can be colored to detect surface defects such as small cracks and pores.
Threaded connections can only be used for pipelines carrying low-pressure, non-hazardous media such as water, compressed air, and nitrogen; they are commonly used for small diameters (up to 40 mm). It is advisable to use hot-dip galvanized pipes and fittings. Large diameters are not suitable for threaded connections, as leakage is likely to occur.
A gas-tightness test is required, but flaw detection is not necessary.