Casting data sheet
*Choose the proper casting position(usually horizontal for specially for cylindrical shapes with flanges, and choose the
parting line)
*Use the following table to pick the suitable shrinkage allowance ( based on the cast material/if not given it could be
assumed)
*Determine the number of core prints based on the cast shape (opened from one or two sides), use the following
table to get the proper core print length:
-D is the diameter of the core, choose either hl or l based on your casting pattern position… l for vertical and hl for
horizontal.
*Use the following table to determine machining allowance (we don’t use cope side, choose surface for outer surfaces
and bore for inner surfaces
2)Charge calculations:
*The matrix M will be given as the percentages of each element contained in the charge(c%,Mn%..etc), get the transpose and
multiply it be the matrix c which is the charges matrix(pig iron- steel scrap ..etc)
-Then get the final compositions by adding the given pick up percentage, multiply by (1-loss percentage) or multiply by (1+gain
percentage).
-Measured strength or hardness will be given in the question.
-Calculate CE and Sc from the compositions you have obtained earlier from matrices.
Eutectic ⇒ CE=4.3, 𝑺𝒄 = 𝟏
Hypo-Eutectic ⇒ CE<4.3, 𝑺𝒄 < 𝟏
Hyper-Eutectic ⇒ CE>4.3, 𝑺𝒄 > 𝟏
*Mg% is the weight of Mg (kg) per 100 kg of the charge, if it is required to calculate per ton charge multiply by 10.
*Atomic weights are given and get S% from your calculations or it will be given also.
*Mg residual is the final composition of Mg in the ductile cast iron after adding Fesi alloy, it will be given but if not take it
0.05%.
*To design gating system:
Calculate the total volume of the cast (mm^3) after dividing for several sections, then change the volume to (m^3) and
multiply it by the density of the cast material to get cast weight (Wc), divide Wc by casting yield (cy) to get the total weight
and calculate pouring time(not solidification time).
*t=1.84(root(Wt)) is used for small casts, it is always preferred to use the other formula, to get average thickness calculate
the thicknesses of the whole shape and divide by their number.
‫افرد الشكل عشان تحسب السمك‬
*Calculate effective height (heff) based on your gating system design, for symmetrical shapes: parting line is preferred.
*Calculate the chock area(Ac) taking friction factor(c) for sand from 0.7 to 0.8 if it was not given, for metal it ranges between
0.9 to 1
4)Riser design:
*Shape factor method is preferred but you can use any of the methods as you like.
*Calculate the whole surface area of the shape then get ratio Vc/Ac and multiply it by 1.2 to get the modulus of the riser which
equlas d/6 for cylindrical shapes (d is the cylinder diameter), you can assume that the height of the riser is equal to the diameter
H=d.
*Lf is the feeding length, it’s a check step to determine if one riser is sufficient or not, T is the average thickness.
Best Wishes