QB /T 2564.3 (PH) - 2012 Screwdriver blades for cross-recessed head screws - Tyep PH

轻工行业QB /T2564.3 (PH) - 2012 QB2564.3 256 十字槽螺钉旋具旋杆 PH型

Unit:

Tip

D	Nominal Blade Diameter
b	max
	min
e	max
	min
f	max
	min
g	max
	min
L	min
α	max
	min
β	max
	min
Minimum test torque/(N · m), M_{for manual use}
Minimum test torque/(N · m), M_machine

3	4.5	6
0.61	1.03	1.56
0.56	0.98	1.51
0.38	0.54	1.13
0.29	0.49	1.08
0.31	0.53	0.64
0.26	0.48	0.59
0.84	1.3	2.31
0.79	1.25	2.26
2.78	2.78	4.37
/	138°30'	140°30'
/	138°00'	140°00'
7°00'	7°00'	5°45'
6°30'	6°30'	5°15'
1	3.5	8.2
1	3.9	10.3

①,a：Length of straight part.
②,b：Blending of flutes dependent on method of manufacture.
③,c：Flutes equally spaced at 90°.
④,d：For tip No. 0, see detail below ( f ).
⑤,e：Section Y-Y: true flute angle measured at right angles to straight part of length L.
⑥,f：Tip No. 0.
⑦,The screwdriver tips shall have a minimum hardness of  54 HRC for hand-operated screwdrivers,  58 HRC for machine-operated screwdrivers, for a minimum length of three times the nominal blade diameter measured from the driving end. The remainder of the tool shall be hardened and tempered to a minimum of 50 HRC.