Tightening Torque and Forces for Bumax Joints

Thread Size and Class	Class	M3	M4	M5	M6	M8	M10	M12	M14
Tightening Torque Mv in Nm (1) (3)	Bumax 109	1.7	4.1	8.1	14	34	66	115	162
	Bumax 88	1.3	2.9	5.7	10	25	47	82	129
	Bumax Lock			6.6	12	29	54	94
Preload Applied +/- 23% (2)	Bumax 109	2.9	5.2	8.6	12	21	34	49	60
	Bumax 88	2.1	3.6	5.9	8.4	15	24	35	48
	Bumax Lock				8.4	15	24	35
Failure Load kN	Bumax 109	5	8.8	14	20	37	58	84	115
	Bumax 88	4	7	11	16	29	46	67	92
	Bumax Lock			11	16	29	46	67
Yield Load kN	Bumax 109	4.5	8	12	18	33	52	76	92
	Bumax 88	3.2	6	9	13	23	37	54	74
	Bumax Lock			9	13	23	37	54
Nominal Stress Area mm2		5.03	8.78	14.2	20.1	36.6	58.0	84.3	115
Pitch of Thread		0.5	0.7	0.8	1.0	1.25	1.5	1.75	2.0

Thread Size and Class	Class	M16	M18	M20	M24	M27	M30	M36
Tightening Torque Mv in Nm (1) (3)	Bumax 109	249	275	481
	Bumax 88	198	275	385	665	961	1310	2280
	Bumax Lock	228		442	765
Preload Applied +/- 23% (2)	Bumax 109	81	100	128
	Bumax 88	65	80	102	181	235	287	418
	Bumax Lock	65		102	181
Failure Load kN	Bumax 109	157	192	245
	Bumax 88	126	154	196	282	367	449	654
	Bumax Lock	126		196	282
Yield Load kN	Bumax 109	125	154	196
	Bumax 88	100	123	157	226	294	359	523
	Bumax Lock	100		157	226
Nominal Stress Area mm2		157	192	245	353	459	561	817
Pitch of Thread		2.0	2.5	2.5	3.0	3.0	3.5	4.0

Thread Size and Class	Class	1/4-20 unc	5/16-18 unc	3/8-16 unc	1/2-13 unc	5/8-11 unc	3/4-10 unc	7/8-9 unc	1"-8 unc
Tightening Torque Mv in Nm (1) (3)	Bumax 88	11	22	39	95	188	329	527	789
Preload Applied Kn +/- 20% (2)	Bumax 88	8.7	14.3	21.1	39.7	61.7	91.2	125.9	165.2
Failure Load Kn	Bumax 88	17	28	41.5	75.9	121	179	247	325
Yield Load Kn	Bumax 88	13.1	22.4	33.2	60.8	96.9	143.4	197.9	259.6
Nominal Stress Area mm2	Bumax 88	20.5	33.8	50.0	91.5	146	216	298	391