Bumax Tightening Data

Thread size and classClassM3M4M5M6M8M10M12M14M16M18M20
Tightening Torque * ***Bumax 1091.74.18.1143466115162248344481
Bumax 881.32.95.710254782129198275385
Bumax Lock  6.612295494 228 442
Preload applied KN ± 23% **Bumax 1092.95.28.6122134496081100128
Bumax 882.13.65.98.4152435486580102
Bumax Lock   8.4152435 65 102
Failure load KNBumax 1094.58131833527692125154196
Bumax 883.269133375474100123157
Bumax Lock  913233754 100 157
Nominal stress area mm² 5.038.7814.220.136.658.084.3115157192245
Pitch of thread 0.50.70.81.01.251.51.752.02.02.52.5

 

Thread size and classClass  M24M27M30M36
Tightening Torque Mv in Nm * ***Bumax 8866596113102280
Bumax Lock765
Preload applied KN ± 23% **Bumax 88181235287418
Bumax Lock181
Failure load KNBumax 88282367449654
Bumax Lock282
Yield Load KNBumax 88226294359523
Bumax Lock226
Nominal stress area mm² 353459561817
Pitch of thread 3.03.03.54.0

 

Thread size and classClass1/4-20 UNC5/16-18 UNC3/8-16 UNC1/2-13 UNC5/8-11 UNC3/4-10 UNC7/8-9 UNC1”-8 UNC
  Tightening Torque Mv in Nm * ***Bumax 8811.022.039.095.0188.0329.0527.0789.0
Preload applied KN ± 23% **Bumax 888.714.321.138.761.791.2125.9165.2
Failure load KNBumax 8817.028.041.575.9121.0179.0247.0325.0
Yield Load KNBumax 8813.122.433.260.896.9143.4197.9259.6
Nominal stress area mm² 20.533.850.091.5146.0216.0298.0391.0

* The Mv recommendations refer to burr-free surfaces lubricated with a good quality lubricant. 

** The preload applied is calculated as 65% of Rp 0.2 but in practice the value can be expected to vary between 50 – 80 % 

*** The Mv-recommendations are calculated assuming a coefficient of friction of 0.16 which requires a good-quality lubricant.

Hole sizes. Torque and forces for Taptite
 Material ThicknessDimensions
M3M4M5M6M8M10
0.1-1.52.703.65    
1.51-2.52.803.654.605.5  
2.51-42.803.704.705.67.59.3
4.01-6.52.853.754.705.67.59.3
6.51-10 3.804.755.657.69.4
10.01-15   5.77.79.5
15.01-20    7.79.6
Breaking Torque in Nm minBumax Hard 4.57.913203052
Standard TT2.23.87.8133245
Tightening Torque Mv i NmBumax Hard 1.336122549
Standard TT1.22.75.49.32240

The Mv recommendations refer to burr-free surfaces lubricated with a good quality lubricant.

The Mv-recommendations are calculated assuming a coefficient of friction of 0.16 that requires a good-quality lubricant

Note: Due to the fact that fastening applications differ greatly, the above information is for guidance only and is correct to the best of our knowledge. The customer must satisfy themselves with the performance of the fastener and validity of the data. TR Fastenings will not be held responsible for any failure that may occur from the use of this information.