ASME B107.15 pdf download FLAT TIP SCREWDRIVERS
5.4.2 Finish. The blade shall be treated in a manner to resist rust or corrosion. There shall be no evidence of peeling or chipping of any coating where applicable.
5.4.3 Hardness. The tip portion of the screwdrivers or the entire blade shall be hardened to not less than 48 HRC (para. 6.2).
5.4.4 Symmetry. See Fig. 3. The tip width shall be perpendicular to the shank axis within 2 dcg. The tip thickness shall be perpendicular to the shank axis within 6 dcg. Taper at the tip shall be centered within 5 deg of the shank axis.
5.5.1 General Requirements. The handle shall be of a material capable of withstanding the applicable test requirements as specified herein. The handle shall be suitably finished to provide a comfortable grip. The handle shall be free from rough edges, sharp corners, or tool marks that affect comfort while using the tool.
5.5.2 Cushion Grip. When specified, the handle shall be furnished with a cushion grip, and the screw- driver shall typically resemble that shown in Fig. 4 The grip material shall be capable of meeting the tests of paras. 6.7 and 6.8. The durometer hardness shall be a maximum of Shore A 75 (para. 6.2). The cushion grip lenguh shall be at least 60% of the handle length, and there shall be no detectable slippage between the handle and the cushion grip under normal usage. A handle with a cushion grip shall meet the dimcnsional requirements for the corresponding conventional type handle for each type and design (see Table 1).
5.6 WORKMANSHIP The screwdriver shall be free from conditions which may impair its serviceability, durability or comfort.
6 TEST PROCEDURES Many tests required herein are inherently hazardous, and adequate safeguards for personnel and property shall be employed in conducting such tesLs. The follow.
applied by forces acting perpendicular to the axis withthe tip held securely in the test block. It is permissibleto support the blade in a suitable position for test.Theblade shall be restricted from endwise movement duringtesting.
6.4Assembly Torsional Test
The tcst shall be conducted after preheating the entiretool to a uniform temperature of 125F土5F (51.7C±2.8C).The lorque shall be applied within 1 minafter renoving the iool from the heating nedium.Thetorque shall be applied by forces acting at or near themiddle of the natural grip of the handle perpendicularto the axis with the tip held securely in the test block.t is perrmissible to support the shank at or ncar thejunction of the shank and handle in a suitable positionfor test. The screwdriver shall be restricted from endwisemovement during testing. When tested to the minimumasscmbly torque value specified in Tablc 2, the assemblyshall not show a permanent slippage between the shankand handle.
6.5 Tip Toughness Test
The tip shall be tested as in the torsion test describedin para. 6.3 except that the torquc shall be increaseduntil failure. If a fracture occurs, the pieces shall berefitted and the tip shall show that permanent deforma-tion had occurred prior to fracture. If the tip fails withoutexhibiting such dcformation.it shall be considered tohave failed the tip toughness test.
6.6 Bending Moment Test
The bending momcnt test for flat tip screwdriversshall be conducted in a manner similar to that shownin Fig. 6. In this test the force shall bc applied nearthe middle of the handle，the force acting at rightangles to the axis of the screwdriver to lift weight w(sec Fig. 6).A load measuring device may be used inlieu of a deadweight in applying the bending load.When tested to the minimum bending moment specified