exhaust gaskets

[Bunje]

hi there
i have recently removed my downpipe to get my bung welded in for my afr meter and noticed that there is no gasket between some parts can anyone tell me if there should be there isnt one between the turbo and turbo elbow. and from the elbow and the downpipe should there be a sealing ring type thingy metal usually and the same at the end of the down pipe where it connects to te exhaust. the reason i ask the questions is because it was all covered in a white powder stuff which i can only presume was some type of exhaust sealer
any help would be much appreciated
Ben

[Markey Mark (BD)]

As standard there were no gaskets on any of those joints, on the bottom of the down pipe there was a metal ring that help seal it alittle but thats all.

[Bunje]

Thanks for the info. I did think that maybe that was how it was supposed to be but just had to make sure