Dimensions of Class 600 Spades for Series A Flanges A285 GrC

Expired

Table below provides spade and spacer dimensions made from ASTM A285 GrC plates for use on Class 600 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.

Spade and Spacer Dimensions

Table for Class 600 Series A Flanges - Material of Spade and Spacer: ASTM A285 GrC

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 3.25 82.55 85.55 862 647 530 45
28 711.2 3.50 88.90 91.90 909 698 555 50
30 762 3.75 95.25 98.25 967 749 585 55
32 812.8 4.00 101.60 104.60 1017 800 610 55
34 863.6 4.25 107.95 110.95 1068 850 635 55
36 914.4 4.50 114.30 117.30 1125 901 665 55
38 965.2 4.75 120.65 123.65 1100 952 650 55
40 1016 5.00 127.00 130.00 1150 1003 675 55
42 1066.8 5.25 133.35 136.35 1214 1054 705 60
44 1117.6 5.50 139.70 142.70 1265 1104 735 60
46 1168.4 5.75 146.05 149.05 1322 1155 760 60
48 1219.2 6.00 152.40 155.40 1385 1206 795 60
50 1270 6.25 158.75 161.75 1443 1257 820 60
52 1320.8 6.50 165.10 168.10 1494 1308 845 60
54 1371.6 6.75 171.45 174.45 1551 1358 875 60
56 1422.4 7.00 177.80 180.80 1608 1409 905 60
58 1473.2 7.25 184.15 187.15 1658 1460 930 60
60 1524 7.50 190.50 193.50 1729 1511 965 60

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 600 the value of P considered is 2250 psi (1500psi x 1.5 = 2250psi)

The value of allowable stress is taken as 90% SMYS of the material. The SMYS for ASTM A285 GrC material as per Table A-1 of ASME B31.3 is 30000 psi. Hence the value of allowable stress S = 27000 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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