What does these welding symbols means?
In these two pictures. One doubt about LS & CS joint and another one is the triangular symbol. Please tell me what is exactly means.
The triangle with the "2" in it looks like a flag note to me, look for a note somewhere with the same symbol, often on sheet 1 .
The little single and double triangles looks non-standard, or of a standard I'm unfamiliar with, so if I'm guessing, it's a shop callout for datums or secondaried surfaces or something.
As Luke Seal said; the double triangle symbol indicates a surface finish around 63 - 125 (N7 - N8)
Here's a little chart I found: http://www.lucefin.com/wp-content/files_mf/roughness.pdf