查看标准

适用范围：<p id="s00002">1.1 This specification covers the requirements for compressible-washer-type direct tension indicators capable of indicating the achievement of a specified minimum bolt tension in a structural bolt. </p> <p id="s00003">1.2 Four types of direct tension indicators in nominal diameter sizes <span class=''unicode''>x00BD;</span> through 1 <span class=''unicode''>x00BD;</span> in. are covered: </p> <p id="s00004">1.2.1 <span class="italic"><span class="italic">Type 325</span>8212;</span>direct tension indicators for use with Specification A 325<astmref rid="a00001"> Type 1 bolts or F or F 1852<astmref rid="a00010"> assemblies.</p> <p id="s00095">1.2.2 <span class="italic"><span class="italic">Type 325<span class=''unicode''>x2013;</span>3</span>8212;</span>direct tension indicators for use with Specification A 325<astmref rid="a00001"> Type 3 or F 1852<astmref rid="a00010"> Type 3 assemblies.</p> <p id="s00005">1.2.3 <span class="italic"><span class="italic">Type 490</span>8212;</span>direct tension indicators for use with Specification A 490<astmref rid="a00002"> Type 1 bolts or F 2280<astmref rid="a00011"> assemblies. </p> <p id="s00094">1.2.4 <span class="italic"><span class="italic">Type 490<span class=''unicode''>x2013;</span>3</span>8212;</span>direct tension indicators for use with Specification A 490<astmref rid="a00002"> Type 3 F 2280<astmref rid="a00011"> Type 3 assemblies.</p> <p id="s00006">1.3 Direct tension indicators are intended for installation under either a bolt head or a hardened washer. (See Research Council on Structural Connections: Specification for Structural Joints Using ASTM A 325 or A 490 Bolts.) </p> <p>1.4 This specification provides for furnishing Types 325<span class=''unicode''>x2013;</span>3 and 490<span class=''unicode''>x2013;</span>3 to a Chemical Composition Requirement or a Corrosion Resistance Index (CRI) at the suppliers option.</p> <p>1.5 The values stated in inch-pound units are to be regarded as standard. No other units of measurement are included in this standard.</p> <p id="s00007">1.6 <span class="italic"><span class="med">The following precautionary statement pertains only to the test method portions, Section 12 and Appendix X1 of this specification: </span><span class="italic">This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. </span> </span>