What do t, tv and ti mean in electrical drawings?

What are sc tube, MT tube, tc tube, KBG tube and JDG tube? Sc: welded steel pipe, TC: thin steel pipe for conducting pipe, pc: rigid plastic pipe, ct: cable tray, cp: metal hose, SR: steel trunking, RC: water pipe and gas pipe, and SC pipes is the initials of the English word steelconduit. The new standard symbol of SC, like the original G, should be electric conduit, and the newly marked TC refers to thin-walled conduit. The above is the so-called welded steel pipe. The new label, PC PVC rigid pipe FPC semi-rigid pipe KPC corrugated pipe CT, laying SC as bridge means steel pipe wiring.