Local 7 Wiki

Section 46: Heel and Throat Using Machinists Figures

PreviousNext

Formulas and Measurements

  • X the decimal of Miters Equivalent - for the # of Miters = Heel Radius - O.D.I.
  • X the decimal - equivalent for the # of Miters + Throat Example: 6" pipe - 1 1/2 X Insulation (Long Radius) - 6 Miters required 6 X 3 =18+9= 27 27 X.131 = 3.5 - Calculate to nearest 1/8" = 3 5/8" - Throat: 6 X 3 =18 -9 = 9 9 X.131 = 1.179 - Calculate to nearest 1/8" = 1 & 1/8" - Heel and Throat Measurements for Miters - Using MITER FORMULA For 90 Degree Elbows - - Heel = Center Line Radius + 1/2 the O.D.I.
  • X 1.57 divided by the # of miters. - Throat = Centerline Radius -1/2 the O.D.I.
  • X 1.57 divided by the # of miters. - Long Radius: The radius will be 1 1/2 times the Pipe Call-Out Size. - Pipe Call-Out Size.
  • 410 - Example: 8X2 Radius X Number of Miters = 6 Center Line Radius + half O.D.I. x 1.57 -:- # of Miters = Heel - 12 + 6.375 x 1.57-:-8 = Heel 18.
  • 375 x 1.57 -:- 8 = Heel 28.84875 -:- 8 = Heei - 3.606 = keel; 3.61 = Heel (changed to a fraction the -'~ E=e1 would be 3 5 8 ) - Center Line Radius - half O.D.I. x 1.57-:-# of Miters = Throat 12-6.375 x 1.57-:-8 = Throat; 5.625 x 1.57 -:- 8 = Throat, - 8.83125 -:- 8 = Throat; 1.103 = Throat (changed to a fraction= 1 1/8") - Example 8X2 Radius # of Miters - Center Line Radius + half 0.0.1. x 1.57-:- 6 = Hee i 8 + 6.375 x 1.57 -:-6 = - 14.375 x 1.57 -:- 6 = s; 22.56875 -:- 6 = Heel; - 3.761 = Heel (changed to a fraction = 3 3/4") - Center Line Radius - half O.D.I. x 1.57-:-6 = Throat:8 - Half O.D.I.
  • X 1.57-:-6 = Throat - 8 - 6.375 X 1.57-:-6 = Throat; 1.625 X 1.57-:-6 = Throat; 2.55125-:-6 = Throat -.425 = Throat (changed to nearest 1/8 would be 1/2 ")

Procedure

  1. Step 1

    Radius + O.D.I.. X the decimal of Miters Equivalent - for the # of Miters = Heel

  2. Step 2

    Radius - O.D.I. X the decimal - equivalent for the # of Miters + Throat Example: 6" pipe - 1 1/2 X Insulation (Long Radius) - 6 Miters required 6 X 3 =18+9= 27 27 X.131 = 3.5 - Calculate to nearest 1/8" = 3 5/8" - Throat: 6 X 3 =18 -9 = 9 9 X.131 = 1.179 - Calculate to nearest 1/8" = 1 & 1/8" - Heel and Throat Measurements for Miters - Using MITER FORMULA For 90 Degree Elbows - - Heel = Center Line Radius + 1/2 the O.D.I. X 1.57 divided by the # of miters. - Throat = Centerline Radius -1/2 the O.D.I. X 1.57 divided by the # of miters. - Long Radius: The radius will be 1 1/2 times the Pipe Call-Out Size. - Pipe Call-Out Size. 410 - Example: 8X2 Radius X Number of Miters = 6 Center Line Radius + half O.D.I. x 1.57 -:- # of Miters = Heel - 12 + 6.375 x 1.57-:-8 = Heel 18. 375 x 1.57 -:- 8 = Heel 28.84875 -:- 8 = Heei - 3.606 = keel; 3.61 = Heel (changed to a fraction the -'~ E=e1 would be 3 5 8 ) - Center Line Radius - half O.D.I. x 1.57-:-# of Miters = Throat 12-6.375 x 1.57-:-8 = Throat; 5.625 x 1.57 -:- 8 = Throat, - 8.83125 -:- 8 = Throat; 1.103 = Throat (changed to a fraction= 1 1/8") - Example 8X2 Radius # of Miters - Center Line Radius + half 0.0.1. x 1.57-:- 6 = Hee i 8 + 6.375 x 1.57 -:-6 = - 14.375 x 1.57 -:- 6 = s; 22.56875 -:- 6 = Heel; - 3.761 = Heel (changed to a fraction = 3 3/4") - Center Line Radius - half O.D.I. x 1.57-:-6 = Throat:8 - Half O.D.I. X 1.57-:-6 = Throat - 8 - 6.375 X 1.57-:-6 = Throat; 1.625 X 1.57-:-6 = Throat; 2.55125-:-6 = Throat -.425 = Throat (changed to nearest 1/8 would be 1/2 ")