CALCULATIONS

Mini riser requirements are based on the modulus of a casting. Exothermic Riser Modulus is defined as the ratio of casting volume divided by the casting surface area. Normally, it is sufficient to calculate the modulus at the thickest section of the casting. Castings can be broken down into simple shapes for this purpose. The following simple shapes will cover practically all castings of exothermic and insulating sleeves.


Bars_graph Cube graph Sphere graph

Bars Calculation:
Casting Modulus = h x w / 2(h +w) where: h = height and w = width

Cube Calculation:
Casting Modulus = s3 / 6 s3 where: s = length of side

Sphere Calculation:
Casting Modulus = d/6 where: d = diameter
Cylinder_graph Rings graph Junctions graph

Cylinder Calculation: Casting Modulus = r x h / 2(r/h) where: r = radius and h = height

Rings Calculation:
Casting Modulus = t x h / 2(t+h) where: t = wall thickness and h = height

 Junctions Calculation:
Casting Modulus, by inscribing a circle over the junction you can treat the calculations as a Cylinder; therefore = r x h / 2(r/h) where: r = radius and h = height of the circle covering the junction.