Square/Allen Drive Working Torque

Drive Size: The square or hex drive of each drive is limited in its maximum output by its material and its engagement area. Since Atlas Copco uses a specially suited alloy-steel for its drive members, the following maximum torque output can be achieved without drive failure, provided the reaction member abuts close to the same plane as the nut to be turned.

If the reaction arm cannot abut on the same plane as the nut to be turned, less torque should be applied, as the additional side load has to be taken into consideration. When toque requirements are close in excess of the values listed above, use RT's/-9/ Sockets Hex-Drive with replaceable Hex Insert Bits.

RT series is available with square drive (standard) or option hexagonal/Allen drive. The table below reviews ideal working range for the respective drives.

Drive Size Inch or mm	Drive Type	Maximum Working Pressure		Probable Failure
Drive Size Inch or mm	Drive Type	ft lbs	Nm	ft lbs	Nm
1/2"	Hex	353	478	392	531
1/2"	Square	367	497	408	553
5/8"	Hex	689	934	766	1038
3/4"	Hex	1191	1614	1324	1794
3/4"	Square	1239	1679	1377	1865
7/8"	Hex	1892	2565	2102	2848
1"	Hex	2824	3827	3138	4252
1"	Square	2937	3980	3263	4422
1-1/8"	Hex	4021	5448	4468	6054
1-1/4"	Hex	5516	7474	6129	8304
1-3/8"	Hex	7341	9948	8157	11053
1-1/2"	Hex	9531	12915	10590	14350
1-1/2"	Square	9912	13432	11014	14924
1-5/8"	Hex	12118	16420	13465	18245
1-3/4"	Hex	15135	20508	16817	22787
1-7/8"	Hex	18616	25224	20684	28027
2"	Hex	22593	30613	25103	34015
2-1/4"	Hex	32168	43588	35742	48431
2-1/2"	Hex	44126	59791	49029	66435
2-1/2"	Square	45891	62183	50990	69092
12mm	Hex	298	404	331	449
17mm	Hex	847	1147	941	1275
19mm	Hex	1182	1602	1313	1780
22mm	Hex	1835	2486	2039	2763
24mm	Hex	2382	3228	2647	3587
27mm	Hex	3392	4596	3769	5107
32mm	Hex	5647	7652	6275	8502
36mm	Hex	8040	10895	8934	12105
41mm	Hex	11878	16094	13197	17882
46mm	Hex	16774	22730	18638	25255
50mm	Hex	21542	29190	23935	32433