Table below provides spade and spacer dimensions made from ASTM A516 Gr70 plates for use on Class 900 Series A flanges.
Read the section at the bottom of table for basis of the calculations for dimensions of spade and spacer.
All dimensions are in "mm" unless noted otherwise.
Table for Class 900 Series A Flanges - Material of Spade and Spacer: ASTM A516 Gr70
| Nom Size Inches |
Pipe OD mm |
Pressure Thickness of Spade Inches |
Pressure Thickness of Spade mm |
Pressure Thickness + 3mm 'T' |
OD of Spade Spacer mm 'A' |
ID of Spacer mm 'D' |
Dimension mm 'B' |
Dimension mm 'C' |
|---|---|---|---|---|---|---|---|---|
| 26 | 660.4 | 3.54 | 89.83 | 92.83 | 877 | 647 | 540 | 65 |
| 28 | 711.2 | 3.81 | 96.74 | 99.74 | 941 | 698 | 570 | 65 |
| 30 | 762 | 4.08 | 103.65 | 106.65 | 1005 | 749 | 605 | 65 |
| 32 | 812.8 | 4.35 | 110.56 | 113.56 | 1068 | 800 | 635 | 65 |
| 34 | 863.6 | 4.62 | 117.47 | 120.47 | 1132 | 850 | 665 | 65 |
| 36 | 914.4 | 4.90 | 124.38 | 127.38 | 1195 | 901 | 700 | 65 |
| 38 | 965.2 | 5.17 | 131.29 | 134.29 | 1195 | 952 | 700 | 65 |
| 40 | 1016 | 5.44 | 138.20 | 141.20 | 1246 | 1003 | 725 | 65 |
| 42 | 1066.8 | 5.71 | 145.11 | 148.11 | 1297 | 1054 | 750 | 65 |
| 44 | 1117.6 | 5.99 | 152.02 | 155.02 | 1363 | 1104 | 780 | 65 |
| 46 | 1168.4 | 6.26 | 158.93 | 161.93 | 1430 | 1155 | 815 | 65 |
| 48 | 1219.2 | 6.53 | 165.84 | 168.84 | 1481 | 1206 | 840 | 65 |
Basis for calculation of Spade and Spacer Dimensions
Spades are used in piping systems to positively isolate sections of piping from one another. The spades are subject to the design pressure and hence the thickness of spades must be able to withstand the design pressure. As per para. 304.5.3(b) of ASME B31.3, the minimum required thickness of a permanent blank shall be calculated in accordance with following equation:
tm = dg\(\sqrt[]{\frac{3P}{16SEW}}\) + c
where
c = sum of allowances (mechanical + corrosion + mill tolerance)
dg = inside diameter of gasket for raised or flat face flanges, or gasket pitch diameter for ring joint and full retained gasketed flanges.
E = quality factor from Table A-1A or A-1B
P = design gage pressure
S = allowable stress value for material from Table A-1
W = weld strength reduction factor
In the calculation of spade thickness, we adopted a slightly different approach which provides conservative values. We know from para. 2.5 of ASME B16.5 that line blanks may be subjected to system tests at a pressure not to exceed 1.5 times the 38°C (100°F) rating rounded off to the next higher 1 bar (25 psi) increment. In the calculation we used a value of P that corresponds to the hydrostatic test pressure (1.5 x Flange Rating Pressure) rounded of to the next higher 25 psi increment.
For Class 900 the value of P considered is 3375psi (2250psi x 1.5 = 3375psi)
The value of allowable stress is taken as 90% SMYS of the material. The SMYS for ASTM A516 Gr70 material as per Table A-1 of ASME B31.3 is 38000 psi. Hence the value of allowable stress S = 34200 psi. E and W are considered as 1 in the equation.
Outside diameter of spade and spacer is calculated as bolt circle diameter of flange minus the bolt hole diameter-1.5mm.
Inside diameter of spacer is calculated as pipe outside diameter minus 6.35 mm.
Dimension B is calculated considering a projection of 75mm of center of handle hole from outside diameter of flange for sizes up to 46 inches and 100mm projection for sizes 48 inches and above.
While calculating dimension 'C' it is checked that the spade and spacer handle can pass through the gap between two adjacent bolts.
The thickness of spade excludes the projection for raised face.
Thickness T in table above assumes sum of allowances 'c' of 3mm.
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