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Fitting Size Chart

MALE NPT IDENTIFICATION CHART

The line drawings below depict the actual sizes of the various common NPT thread sizes. If you are unsure as to what thread size you are using lay your fitting over the appropriate drawing to determine its size.

npt-chart

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MALE AN/ORB ADAPTER IDENTIFICATION CHART
The line drawings below depict the actual sizes of the various common AN/ORB thread sizes. If you are unsure as to what size fitting you have lay your fitting over the appropriate drawing to determine its size.ย NOTE:ย - AN and ORB thread are the same diameter. AN seals with the flare, ORB seals with an O-ring.

an-orb-chart

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AN HEX OD IDENTIFICATION CHART
The line drawings below depict the actual sizes of the various common types of fittings, hose ends and adapters. The number is SAE spanner size equivalent.

an-hex-chart

NPT (National pipe Thread)

Thread Size Threads Per Inch Closest AN Size
1/16" 27 3
1/8" 27 4
1/4" 18 6
3/8" 18 8
1/2" 14 10
3/4" 14 12
1" 11-1/2 16
1-1/4" 11-1/2 20
1-1/2" 11-1/2 24
2" 11-1/2 32

AN NUT

Hex Sizes B Nut AN Side S Nut Hose Side
-3 1/2" 1/2"
-4 9/16" 1/4"
-6 11/16" 19/64"
-8 7/8" 7/8"
-10 1" 1-1/16"
-12 1-1/4" 1-3/16"
-16 1-1/2" 1-7/16"
-20 1-13/16" 1-3/4"
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AN THREAD

Thread Size Thread Size SAE Threads Per Inch Max Torque ft/lbs
-3 3/8 24 8.75
-4 7/16 20 11.5
-5 1/2 20 14.3
-6 9/16 18 16.25
-7 5/8 18 19.5
-8 3/4 16 29
-10 7/8 14 35
-12 1-1/16 12 45
-16 1-5/16 12 70
-20 1-5/8 12 85