ASTM D622-99(R2019) pdf free download
ASTM D622-99(R2019) pdf free download.Standard Test Methods for Rubber Hose for Automotive Air and Vacuum Brake System
1. Scope
1.1 These test methods are intended for use in testing the conventional types of hose employed for the operation of air brake and vacuum brake systems, 2 either on a single motor vehicle or as connecting or transmission lines in a combination of vehicles. The hose may be assembled with suitable metal couplings or may be as fabricated for use with detachable fittings. The term “rubber” as used in these test methods includes synthetic compounds as well as compounds of natural rubber. 1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. 1.3 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 appro- priate safety, health, and environmental practices and deter- mine the applicability ofregulatory limitations prior to use. 1.4 This international standard was developed in accor- dance with internationally recognized principles on standard- ization established in the Decision on Principles for the Development of International Standards, Guides and Recom- mendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
8. Adhesion Test
8.1 Fiber Reinforced Hose—Conduct the adhesion test be- tween component parts of fiber reinforced hose in accordance with Test Methods D413, Machine Method. 8.2 Wire Reinforced Hose—Conduct the adhesion test on specimens with a minimum length of380 mm (15 in.) prepared from the original sample without having been subject to previous tests. 8.2.1 Procedure—Place a steel ball of the size specified in Table 1 in the bore of the hose. Completely close one end against air leakage and connect the other end to a vacuum pump. Subject the bore of the hose to a reduced pressure (vacuum) of 85 kPa (25 in. Hg) for a period of 5 min while in an essentially straight position. At the end of this period and while still under the reduced pressure, bend the hose 3.14 rad (180°) to the minimum radius specified in Table 2 in each of two directions 3.14 rad (180°) apart. 8.2.1.1 After bending and returning to an essentially straight position and while still under reduced pressure, the ball shall be rolled from end to end of the hose. Failure of the ball to pass freely from end to end shall be an indication of separation of the tube from the carcass due to inadequate adhesion. Report any separation.
9. Ozone Resistance Test
9.1 Bend a specimen of hose of full circumference around a mandrel and tie the ends together where they cross one another with tie wire. The mandrel shall be a diameter twice the minimum bend radius specified in Table 2 for air brake hose and 8 times the nominal outside diameter for vacuum brake hose. The specimen length shall be about 250 mm (10 in.) longer than the mandrel circumference. Seal the ends of the hose with plugs on caps in such a manner that the reinforce- ment and inner tube will not be exposed to ozone. 9.2 Condition the hose for 24 6 1 ⁄ 2 h in air at room temperature and while still on the mandrel place in an exposure chamber in accordance with Test Method D1149, containing air mixed with ozone, with ozone at a partial pressure of 50 6 5 mPa (formerly expressed as pphm, see Test Method D1149 for explanation). The ambient air temperature in the chamber during the test shall be 40 6 2°C (104 6 3.6°F). Expose the specimen to the ozone and air mixture for a period of 70 6 2 h. To determine conformance to this requirement, examine the cover of the specimen under 7× magnification, ignoring areas immediately adjacent to or within the area covered by the tie wire. 9.3 Report any cracks.
