these are the gardes defined in ASTM/ASME A216 has three grades viz.. WCA, WCB & WCC for carbon steel castings
with slight variations in chemical/mechanical values
for WCB
c 0.3%
Mn 1%
P 0.04%
S 0.045%
si 0.6% all are Max and other specified residual elements
with 485-655 Mpa UTS, 250Mpa YS Min...
hidrogen induced cracking this will be done as per NACE standrd TM-02-84
stressed specimen will be kept under corrissive atm. for a perticular period, normally 120 hours
test conditions as per the above standard
there are gap o lets available in the market to maintain this gap. it just like a spring washer with dif. MOC are available. Very simple and easy to use
