astm a325

ASTM A325From Wikipedia, the free encyclopedia

ASTM A325 is an ASTM International standard for heavy hex structural bolts, titled Standard Specification forStructural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength. It defines mechanical propertiesfor bolts that range from 1

2 to 1-1 2 in diameter.[1]

The equivalent metric standard is ASTM A323M, which is titled Standard Specification for Structural Bolts,Steel, Heat Treated 830 MPa Minimum Tensile Strength. It defines mechanical properties for sizes M12–36.[2]

There is also a T version, which is used to refer to fully threaded bolts.[3]

This is a standard set by the standards organization ASTM International, a voluntary standards developmentorganizations that sets technical standards for materials, products, systems, and services.

Contents

1 Types2 Connection types3 Mechanical properties4 References

Types

The type refers to the type of material used to make the bolt. The standard currently defines two types, howeverit previously defined the following three:[3]

Type 1: Medium carbon steel, boron steel, or medium carbon alloy steelType 2: Low carbon martensitic steel[4] (withdrawn from the standard in 1991)Type 3: Weathering steel

Note that independent of the material the bolt is quenched and tempered.[4]

Connection types

There are also three connection types defined:[3]

SC: A slip critical connection.N: A bearing type connection where the threads are on the shear plane.X: A bearing type connection where the threads are not on the shear plane.

Mechanical properties

These types of bolts are designed to be tightened to near their proof strength, in order to create significant bolt

ASTM A325 - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/ASTM_A325

1 of 3 28/08/2012 4:16 PM

tension. The standard states that the bolts must be tightened to at least 70% of the tensile strength. These boltsuse the same material as their common cousins (ASTM F568M for metric bolts), but have a thicker and widerhead to more effectively distribute the load. This modified geometry is often referred to as heavy hexgeometry.[5]

ASTM 325 bolts can be considered equivalent to Grade 8.8 bolts according to ASTM F568M.

For a higher strength version of this type of bolt, see ASTM A490.

Head markings and mechanical properties for imperial sizes[4]

Head marking Grade Nominal sizerange [in]

Proofstrength

[ksi]

Yieldstrength

(min) [ksi]

Tensilestrength (min)

[ksi]

Core hardness[Rockwell][6]

or

[6]

Type1

12–1 (inc.) 85 92 120 C24–35

1–1-12 74 81 105 C19–31

Type2

12–1 85 92 120 C24–35

[7] Type3

12–1 85 92 120 C24–35

1–1-12 74 81 105 C19–31

Head markings and mechanical properties for metric sizes[5]

Headmarking Grade Nominal size

range [mm]

Proofstrength[MPa]

Yield strength(min) [MPa]

Tensile strength(min) [MPa]

Core hardness[Rockwell]

Type1

12–36[2] 600 660 830 C23–34Type2

Type3

References^ ASTM A325 - 09 (http://www.astm.org/Standards/A325.htm) , http://www.astm.org/Standards/A325.htm, retrieved1.


2 of 3 28/08/2012 4:16 PM

2009-06-13.^ a b ASTM A325M - 09 (http://www.astm.org/Standards/A325M.htm) , http://www.astm.org/Standards/A325M.htm,retrieved 2009-06-13.

2.

^ a b c ASTM A325 (http://www.portlandbolt.com/technicalinformation/astm/ASTM_A325.html) ,http://www.portlandbolt.com/technicalinformation/astm/ASTM_A325.html, retrieved 2009-06-13.

3.

^ a b c ASTM, SAE and ISO grade markings and mechanical properties for steel fasteners(http://www.americanfastener.com/technical/grade_markings_steel.asp) , http://www.americanfastener.com/technical/grade_markings_steel.asp, retrieved 2009-06-06.

4.

^ a b Metric structural fasteners (http://www.icaen.uiowa.edu/~sdesign1/Text/fasteners_si.html) ,http://www.icaen.uiowa.edu/~sdesign1/Text/fasteners_si.html, retrieved 2009-06-06.

5.

^ a b Grade Markings: Carbon Steel Bolts (http://www.fastspecinc.com/technical/technical.html) ,http://www.fastspecinc.com/technical/technical.html, retrieved 2009-05-30.

6.

^ Other markings may be used to denote atmospheric corrosion resistant material7.

Retrieved from "http://en.wikipedia.org/w/index.php?title=ASTM_A325&oldid=499557441"Categories: ASTM standards Screws

This page was last modified on 18 August 2012 at 21:56.Text is available under the Creative Commons Attribution-ShareAlike License; additional terms mayapply. See Terms of use for details.Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.


3 of 3 28/08/2012 4:16 PM

astm a325

Documents