Bumax Stainless Steel Fasteners

 
 
Composition and corrosion resistance data 
Steel Grade Acid Resistant
Designation: 7)  
ISO group A4
ISO No. 20a
Bulten Stainless Bumax
SS 14. 2343
Avesta 832 SK
Fagersta P440
Sandvik 5R60
Uddeholm 24
EN Name 1) X3CrNiMo 17133
EN 10027-2 1.4436
USA (AISI) 1) -
U K (BS) 1) -
France (AFNOP) 1) Z6CND 17-12
Italy (UNI) 1) X5CrNiMo 1713
Japan (JIS) 1) -
Chemical Composition
Carbon C % max. 0.03
Chromium Cr % 16.5-18.5
Nickel Ni % 11.0 – 14.5
Molybdenum Mo % 2.5-3.0
Cuppar Cu % -
Stabiliser Ti/Nb % -
Structure Austenitic
 
Physical Data
Magnetic No
Scalling temperature. In air appr °C 850
Machining Properties
Hardenabillity No
Weldabillity Excellent (5)
Notes
Used in the cellul-lose and in Pulp & Paper industry. The low carbon and the increased content of Cr. Ni and Mo gives the steel excellent resistance to corrosion.
 


Bumax Stainless Steel Fasteners - Tightening Data
 

Thread size and class Class M3 M4 M5 M6 M8 M10 M12 M14 M16 M18 M20
Tightening Torque * *** Bumax 109 1.7 4.1 8.1 14 34 66 115 162 248 344 481
Bumax 88 1.3 2.9 5.7 10 25 47 82 129 198 275 385
Bumax Lock     6.6 12 29 54 94   228   442
Preload applied KN ± 23% ** Bumax 109 2.9 5.2 8.6 12 21 34 49 60 81 100 128
Bumax 88 2.1 3.6 5.9 8.4 15 24 35 48 65 80 102
Bumax Lock       8.4 15 24 35   65   102
Failure load KN Bumax 109 4.5 8 13 18 33 52 76 92 125 154 196
Bumax 88 3.2 6 9 13 3 37 54 74 100 123 157
Bumax Lock     9 13 23 37 54   100   157
Nominal stress area mm²   5.03 8.78 14.2 20.1 36.6 58.0 84.3 115 157 192 245
Pitch of thread   0.5 0.7 0.8 1.0 1.25 1.5 1.75 2.0 2.0 2.5 2.5

 

Thread size and class Class   M24 M27 M30 M36
Tightening Torque Mv in Nm * *** Bumax 88 665 961 1310 2280
Bumax Lock 765
Preload applied KN ± 23% ** Bumax 88 181 235 287 418
Bumax Lock 181
Failure load KN Bumax 88 282 367 449 654
Bumax Lock 282
Yield Load KN Bumax 88 226 294 359 523
Bumax Lock 226
Nominal stress area mm²   353 459 561 817
Pitch of thread   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 * *** Bumax 88 11.0 22.0 39.0 95.0 188.0 329.0 527.0 789.0
Preload applied KN ± 23% ** Bumax 88 8.7 14.3 21.1 38.7 61.7 91.2 125.9 165.2
Failure load KN Bumax 88 17.0 28.0 41.5 75.9 121.0 179.0 247.0 325.0
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   20.5 33.8 50.0 91.5 146.0 216.0 298.0 391.0

* 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.



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.