F959

Scope

ASTM F959 covers the requirements for compressible washer type direct tension indicators in diameters ranging from 1/2” to 1-1/2” inclusive. These washers are capable of indicating the achievement of a specified minimum bolt tension. They are available in two grades for use with A325 and A490 structural bolts and are also available in a weathering steel option for both grades.

F959 Types

Type 325 and 325-3

Type 490 and 490-3

For use with A325, F1852 and A325-3, F1852-3 structural bolts

For use with A490, F2280 and A490-3, F2280-3 structural bolts

F959 Acceptable Compression Load Range

Diameter

Type 325 and 325-3, in kips

Type 490 and 490-3, in kips

1/2

12 – 14

15 – 18

5/8

19 – 23

24 – 29

3/4

28 – 34

35 – 42

7/8

39 – 47

49 – 59

1

51 – 61

64 – 77

1-1/8

56 – 67

80 – 96

1-1/4

71 – 85

102 – 122

1-3/8

85 – 102

121 – 145

1-1/2

103 – 124

148 – 178

F959 Chemical Requirements, Heat Analysis

 

Element

Type 325 and 490

Type 325-3 and 490-3

Carbon

0.30 – 0.55%

Manganese

0.50 – 0.90%

Phosphorous, max

0.040%

0.040%

Sulfur, max

0.045%

0.050%

Silicon

0.15 – 0.35%

0.15 – 0.35%

Chromium

0.45 – 0.65%

Nickel

0.25 – 0.45%

Copper

0.25 – 0.45%

  • List Item Weathering steel DTIs may also be made from any of the type 3 steels listed in A325 and F4361

  • List ItWeathering Steel DTIs having Copper, Sulfur, and Phosphorous conforming to the above, and having a Corrosion Resistance Index of 6 or higher calculated on the basis of the heat analysis as described in Guide 101 Predictive Method based on the data of Larabee and Coburn shall be considered acceptable.em 2