High tensile strength stainless
fasteners
BUFAB STAINLESS HISTORY1674 Svartå Bruk was founded1912 Svartå Bruk was
incorporated into the Hasselfors group.
1947 Production of Stainless Steel Fasteners started.
1966 The melting house was closed down.
1975 Change of name to Hasselfors Stainless.
1660 Åshammar Forging & Nail Factory was founded.
1899 Åsh Forging & Nail change to Åshammars Bolt Factory and the fastener production started.
1926 Production of Stainless Steel fasteners started.
1947 Åsh Bolt Factory was incorporated into the the Bulten group.
1982 The two companies merged into Bulten Stainless
1992 The cold heading were moved to Åshammar and Svartå concentrated in machining / marketing/ logistics.
2000 Finnveden invest, the new owner of Bulten.
2004 Change of name to Bufab Stainless AB
2005 Nordic Capital acquire Finnveden and divide Bufab as
own group from Finnveden
The ”Good old days”
Fastener production 1904
The Bulten head office 1897
Volvo Ocean Race(former Whitbread Round the World Race)
Volvo Ocean Race. ASSA Abloy.12 PCs of M30 Bolts = 11 Kg
Strength 1550 MPa ~225 ksi
Whitbread Round theWorld Race.EF Language.18 PCs of M39 Bolts = 36 Kg
Strength 700 MPa ~101 ksi
Technique• Cold heading• Hot forging• Machine finishingMachines• Cold headers• Thread rollers• CNC machines• Nut formers• Hot forging linesSize range• M2 - M42
Production
• Design• Production• Know-how • Technical support
Engineering
Quality• ISO 9001• ISO 14001• QS 9000• PED No 97/23/EC
High performance products
Unique products• BUMAX 88• BUMAX 109• BUMAX 129 • BUMAX LDX (Under development)• BUMAX 149 – 200 (Under development)• BUMAX HARD• High temperature products
For end users with stringent requirements for the best performance
• The strongest stainless steel fasteners in the market• Lower weight, higher strength• Superior resistance to corrosion• High and low temperature • Non-magnetic• Complete assortment in stock
The benefits of BUMAX
8.8
10.9
12.9
BUMAX 88
BUMAX 109
BUMAX 129
BUMAX 149
BUMAX 200
A4-80Steel bolt standard Stainless steel
bolt standard
Tensile strength 1 200 MPa (174 ksi)
Yield strength 90% of 1 200 = 1 100 MPa (160 ksi)
Strength Range Tensile strength Yield strength ElongationGroup/type class Rm Rp 0.2
M Inch N/mm2 PSI N/mm2 PSIA4-80 (316) 80 M5 - M24 3/16 - 1 800 116,000 600 87,000 0.3 x dBUMAX 88 80 M3 - M36 1/8 - 1 3/8 800 116,000 640 92,800 0.4 x d
BUMAX 109 100 M6 - M12 1/4 - 1/2 1000 145,000 900 130,500 0.2 x d
Mechanical properties
• 1 Mpa = 1 N/mm2 = 145 psi
• BUMAX 88/109 are made in material 316L HiMo
• PED elongation min 0.4 x D
0
400
600
800
1 000
1 200
200
N/mm2
800
1 100
640760
900980
9301 000
BUMAX 88 BUMAX 109 BUMAX 88 BUMAX 109
Specification
Typical testresult
Tensile(Rm)
Tensile(Rm)
Yield(Rp)
Yield(Rp)
M20 M14 M12 M10A4-50 A4-70 88 109
• Lower weight• Higher strength• Smaller screw joints• Replace 8.8 and 10.9
Steelgrade C max Cr Ni MoA2 (304) 0.08 18.0 - 20.0 8.0 - 10.0A4 (316) 0.08 16.0 - 18.0 10.0 - 14.0 2.0 - 2.5BUMAX (316L HiMo) 0.03 16.5 - 18.5 11.0 - 14.5 2.5 - 3.0
Chemical composition
% sulphuric acidEN ASTM 3 10 20
1.4301 304 1.08 3.001.4401,1.4404 316,316L 0 0.32 1.30
1.4436 316L HiMo (BUMAX) 0 0.04 0.44
General corrosionTest in Sulphuric acid H2SO4 at 50 C (122 F)
The corrosion rate is expressed as mm/year(Test made by Sandvik, Sweden)
Pitting/crevice CorrosionPRE-value (Pitting Resistance Equivalent)
PRE = % Cr + 3,3 x % Mo + 16 x % N
PRE > 40 is totally resistance against pitting/crevice corrosion in sea-waterPRE >40 (254 SMO,SAF 2507) BSI manufactures in these steels
EN ASTM % Cr % Mo % N PRE1.4301 304 16.0 - 18.0 16.00 - 18.00
1.4401,1.4404 316,316L 16.0 - 18.0 2.0 - 2.5 22.60 - 26.251.4436 316L HiMo (BUMAX) 16.5 - 18.5 2.5 - 3.0 24.75 - 28.40
CR.
10
9
8
7
6
5
4
3
2
1
0
12 14 16 18 20 22 24 26 28 30 32 PRE
Pitting/crevice CorrosionPRE-value (Pitting Resistance Equivalent)
PRE = % Cr + 3,3 x % Mo + 16 x % N
Corrosion rating after ten years expose to marine atmosphere as a function of alloying element content. (CR up to 3 = no corrosion)
AISI 304L
AISI 316L
Bumax
CR3
Steel grade Yield strength Maximum relative permabilityand class N/mm2 PSI km
A2-70 (304) 450 65,000 1.400A2-80 (304) 600 87,000 1.800A4-80 (316) 600 87,000 1.012BUMAX 88 (316L HiMo) 640 92,800 1.006BUMAX 109 (316L HiMo) 900 130,500 1.007
Permeability
Permeability is a measurement on a materials ability to let a magnetic field go through and it’sdescribed as the permeability value km. This is the value for the permeability of a material inrelation with to vacuum, where Km 1,000 is totally non-magnetic.
BUMAX can be regarded as non magnetic.
High temperature applications
Remaining Yield strength in % of RTSteel and 100ºC 200ºC 300ºC 400ºC 500ºC 600ºCstrength class 218 F 398 F 578 F 758 F 938 F 1118 FA4 80 (316) 85 80 75 70BUMAX 88 90 90 85 80 75 70BUMAX 109 95 95 95 90 90 85
Mechanical properties at high temperature
Note: creep strength at around 550ºC
BUMAX 88 PED can be used from -200 ºC up to 400 ºC
The solution(Working temperature 350 - 450ºC)
BUMAX 88M36 studs + nuts
• Higher temperature resistant• Higher strength• Higher tightening torque
Pressure vessel fastenersapproved by TÜV toPED No 97/23/EC
(2002-06-01)
Pressure equipment
> 0,5 barabove
atmospheric
Pressure
(1013mbar)
M8
A2/A4-505.6
A2/A4-708.8
PED200 MPa (SS)200 MPa (S)
ADW 2450 MPa (SS)640 MPA (S)
Before PED 2002-05-30
M8 (SS)
M8 (S) M14/16
(S)
M10/12(SS)
2002-08-01
BUMAX 88640 MPa (SS)
BUMAX 88
M6
Mechanical propertiesTensile strength Rm N/mm2 1 200 (174 ksi)Yield strength RP 0,2/mm2 1 100 (160 ksi)Elongation min 0,2 x d
Material • 254 SMO • 1.4313
Chemical compositionC 0,02 Cr 19,5-20,5 Ni 17,5-18,5 Mo 6,0-7,0C 0,05 Cr 12,0-14,0 Ni 3,5-4,5 Mo 0,3-0,7
Material under testing.LDX 2101, EN 1.4161 (Outokumpu, former Avesta polarit)
BUMAX 129 (special item)
Dacromet
Zinc
Copper
Silver
Surface treatment
Material Outokumpu LDX (Lean Duplex)
StandardsEN 1.4162 ASTM 32101
Mechanical propertiesTensile strength Rm N/mm2 1 250Yield strength Rp 0,2/mm2 1 020Elongation min > 0,85 x d
Corrosion resistanceIn between A2 and A4 – closer to A4
Chemical compositionC 0,03 N 0.22 Cr 21.5 Ni 1.5 Mo 0.3
BUMAX LDX
Mechanical propertiesTensile strength Rm N/mm2 1 400 - 2 000 (203 - 290 ksi)Yield strength RP 0,2/mm2 1 200 - 1 800 (174 - 261 ksi)Elongation min < 0,2 x d
Material Sandvik Nanoflex
Chemical compositionC 0,02 Cr 12,0 Ni 9,0 Mo 4,0 Cu 2,0 Ti 0,9 Al 0,4
BUMAX 149 – 200 (Under development)
We have reached
Rm 1 700 N/mm2
RP 1 600 N/mm2