DIN 916 internal hexagon socket set screws, also known as headless screws, feature a recessed end with a normal internal hexagon socket. The screw’s end is concave, commonly referred to as internal hexagon socket set screws or internal hexagon socket stop screws. While internal hexagon socket set screws are generally used to fix the relative positions of 2 lightly loaded components, internal hexagon socket set screws with a recessed end provide enhanced reliability and can withstand greater forces.
internal hexagon socket set screw AGICO Supply
AGICO supplies DIN 616 hexagon socket set screw thread sizes ranging from M1.4 to M24
Bolt grade grades including 45H, A2, A4, C3, CU2, CU3, and AL4
If you are interested in buying stainless carriage bolt, contact us now !
dimensions table for DIN 916 internal hexagon socket set screws:
Thread specification d
Pitch P
dp
df ≈
e min
s
tmin
L
max
min
Nominal
max
min
M1.4
0.3
0.7
0.45
Thread diameter
0.803
0.7
0.711
0.724
0.6
1.4
2.5-6
M1.6
0.35
0.8
0.55
0.803
0.7
0.711
0.724
0.7
1.5
2.5-6
M1.8
0.35
0.9
0.65
0.803
0.7
0.711
0.724
0.8
1.6
2.5-6
M2
0.4
1
0.75
1.003
0.9
0.889
0.902
0.8
1.7
3-10
M2.5
0.45
1.2
0.95
1.427
1.3
1.27
1.259
1.2
2
3-10
M3
0.5
1.4
1.15
1.73
1.5
1.52
1.545
1.2
2
4-20
M4
0.7
2
1.75
2.3
2
2.02
2.045
1.5
2.5
4-20
M5
0.8
2.5
2.25
2.87
2.5
2.52
2.56
2
3
5-25
M6
1
3
2.75
3.44
3
3.02
3.08
2
3.5
6-35
M8
1.25
5
4.7
4.58
4
4.02
4.095
3
5
8-40
M10
1.5
6
5.7
5.72
5
5.02
5.095
4
6
12-40
M12
1.75
8
7.64
6.86
6
6.02
6.095
4.8
8
16-40
M14
2
9
8.64
6.86
6
6.02
6.095
5.6
9
M16
2
10
9.64
9.15
8
8.025
8.115
6.4
10
20-40
M18
2.5
12
11.57
11.43
10
10.025
10.115
7.2
11
M20
2.5
14
13.57
11.43
10
10.025
10.115
8
12
20-40
M22
2.5
16
15.57
13.72
12
12.032
12.142
9
13.5
M24
3
16
15.57
13.72
12
12.032
12.142
10
15
30-60
Except for M1.4, M1.6, M1.8, M2, and M2.5, emin = 1.14Smin. tmin denotes the minimum engagement depth for short screws and long screws.
Nominal length L range:
L
Nominal
min
max
2
1.8
2.2
2.5
2.3
2.7
3
2.8
3.2
3.5
3.26
3.74
4
3.76
4.24
5
4.76
5.24
6
5.76
6.24
8
7.71
8.29
10
9.71
10.29
12
11.65
12.35
14
13.65
14.35
16
15.65
16.35
18
17.65
18.35
20
19.58
20.42
22
21.58
22.42
25
24.58
25.42
28
27.58
28.42
30
29.58
30.42
35
34.5
35.5
40
39.5
40.5
45
44.5
45.5
50
49.5
50.5
55
54.4
55.6
60
59.4
60.6
Marking Method of DIN 916 hexagon socket set screw :
For a screw with thread specification d = M6, nominal length L = 12mm, performance grade 45H, and surface oxidation treatment, the marking for an internal hexagon socket set screw is:
Internal Hexagon Socket Set Screw DIN 916-M6x12
Material and Performance of DIN 916 Hex Socket Screws:
Materials for DIN 916: carbon steel, stainless steel, and non-ferrous metals.
Performance grade of screws and bolts: DIN 916 hex socket screw tensile strength, such as 4.8, 8.8, 10.9, etc., while the performance grade of set screws is indicated by hardness, divided into four grades: 14H, 22H, 33H, and 45H.
chemical composition of carbon steel internal hexagon socket set screws
Performance level
Material
heat treatment
chemical composition%
C
P
S
max
min
max
max
45H
alloy steel
Quenched and tempered
0.5
0.19
0.05
0.05
Mechanical properties of DIN 916 carbon steel internal hexagon socket set screws
Performance level
Vickers hardness HV10
Brinell hardness HB
Rockwell hardness HRC
Minimum height Emin of non-decarburized layer of thread
Surface hardness HV0.3
min
max
min
max
min
max
45H
450
560
428
532
45
53
3/4H1
580
Guaranteed torque for carbon steel internal hexagon socket set screws: Carbon steel internal hexagon socket set screws also require surface treatment, which is the process of forming a covering layer on the surface of the workpiece through certain methods to enhance aesthetics and achieve corrosion resistance. Surface treatment methods include oxidation, electroplating, and non-electrolytic zinc plating.
Thread nominal diameter d
3
4
5
6
8
10
12
16
20
24
Minimum length of test screw mm
5
6
6
8
10
12
16
20
25
30
Guaranteed torque Nm
0.9
2.5
5
8.5
20
40
65
160
310
520
stainless steel internal hexagon socket set screw chemical composition
The material used for stainless steel internal hexagon socket set screws is austenitic stainless steel, commonly SUS304 and SUS316. The chemical composition is as follows:
category
Material
chemical composition%
C
Si
Mn
P
S
Cr
Mo
Ni
Cu
austenite
SUS304
0.1
1
2
0.05
0.03
15~20
—
8~19
4
SUS316
0.08
1
2
0.045
0.03
16~18.5
2~3
10~15
1
The performance grades for stainless steel hexagon socket screws are divided into 2 categories, also indicated by hardness: 12H and 21H. 12H indicates that the minimum Vickers hardness for soft austenitic steel is 125HV, while 21H indicates that the minimum Vickers hardness for cold-worked austenitic steel is 210HV. The performance grade of stainless steel internal hexagon socket set screws is 21H.
Guaranteed torque for stainless steel internal hexagon socket set screws:
Thread nominal diameter d
1.6
2
2.5
3
4
5
6
8
10
12
16
20
24
Minimum length of test screw mm
2.5
3
4
5
6
6
8
10
12
16
20
25
30
Guaranteed torque Nm
0.05
0.1
0.3
0.42
1.4
2.8
5
12
24
42
105
210
332
Applications of DIN 916 Internal Hexagon Socket Set Screws:
DIN 916 internal hexagon socket set screws are commonly used in applications where the screw head must not protrude, suitable for machinery with high hardness or frequent positional adjustments. Due to the ease of sinking into components and providing a smooth surface, internal hexagon socket set screws find wide applications in industries such as mechanical equipment, electronic devices, communication equipment, hardware lighting, various precision machinery and instruments, electronics, communication products, locks, and more.
The DIN 603 carriage bolt has a large round head with a square neck underneath, it is also known as the large round head square neck bolt. It is generally used in conjunction with a nut to securely fasten and connect 2 parts with holes.
When inserted into a slot, the square neck under the head of the carriage bolt fits into the slot of the connected piece, preventing the bolt from rotating in the same direction during installation and allowing for parallel movement within the slot.
Din 603 Carriage Bolts from AGICO
AGICO supplies DIN 603 carriage bolt in the material of a2, a4, which is also named sus304.
Bolt grade 5.0, 7.0, 8.0,
Common Dimensions: m5, m6, m8, m10, m12, m14, m16, m20.
If you are interested in buying stainless carriage bolt, contact us now !
DIN 603 Carriage Bolt Standard Specification:
Nominal diameter d
M5
M6
M8
M10
M12
M16
M20
Pitch p
0.8
1
1.25
1.5
1.75
2
2.5
b
L≤125
16
18
22
26
30
38
46
125≤L≤200
22
24
28
32
36
44
52
L>200
/
/
41
45
49
57
65
dk
max
13.55
16.55
20.65
24.65
30.65
38.8
46.8
min
12.45
15.45
19.35
23.35
29.35
37.2
45.2
ds
max
5
6
8
10
12
16
20
min
4.52
5.52
7.42
9.42
11.3
15.3
19.16
k
max
3.3
3.88
4.88
5.38
6.95
8.95
11.05
min
2.7
3.12
4.12
4.62
6.05
8.05
9.95
s
max
5.48
6.48
8.58
10.58
12.7
16.7
20.84
min
4.52
5.52
7.42
9.42
11.3
15.3
19.16
f
max
4.1
4.6
5.6
6.6
8.75
12.9
15.9
min
2.9
3.4
4.4
5.4
7.25
11.1
14.1
DIN 603 Carriage Bolt Standard:
The DIN 603 carriage bolt follows the German standard DIN603-1981, specifying metric thread sizes ranging from M5 to M20 and product grades as grade C carriage bolts.
Drawing of DIN 603 Carriage Bolt:
Marking Method for DIN603 Carriage Bolt
Example marking: Thread specification d = M10, nominal length L = 60mm, uncoated round head square neck bolt marking: Carriage Bolt DIN603-M10*60
Material and Mechanical Properties of DIN603 Carriage Bolt
DIN603 bolts are classified into carbon steel carriage bolts and stainless steel carriage bolts. The performance grades for carbon steel carriage bolts are 3.6 and 4.8. Standards can be referenced to GB3098.1, with chemical composition as shown below:
Performance level
Material
chemical composition%
C
P
S
B
min
max
max
max
max
3.6
carbon steel
–
0.2
0.05
0.06
0.003
4.8
–
0.55
0.05
0.06
0.003
3.6 and 4.8 grades permit the use of free-cutting steel, with maximum sulfur, phosphorus, and lead content of 0.34%, 0.11%, and 0.35%, respectively.
Material
Performance level
Vickers hardness HV
Brinell hardness HB
Rockwell hardness HR
Nominal tensile strength
Minimum tensile strength
Yield point
guaranteed stress
Elongation after break
min
max
min
max
min
max
Nominal
min
carbon steel
3.6
95
220
90
209
52
95
300
330
180
190
180
25
4.8
130
220
124
209
71
95
400
420
320
340
310
–
Mechanical Properties of Carbon Steel Carriage Bolts
The material for DIN 603 stainless steel carriage bolts is SUS304. The material and chemical composition of stainless steel carriage bolts are:
Use material
Chemical Composition%
C
And
Mn
P
S
Cr
Mo
In
With
SUS304
0.1
1
2
0.05
0.03
15-20
–
8-19
4
Material
category
Group
Performance level
Thread diameter
tensile strength
Specify non-proportional elongation stress
Elongation after break
Stainless steel
austenite
A2、A4
50
≤M39
500
210
0.6d
70
≤M24
700
450
0.4d
80
≤M24
800
600
0.3d
Mechanical Properties of Stainless Steel Carriage Bolts
Application of DIN 603 Carriage Bolt
DIN 603 Carriage bolts are commonly used in dry-hanging marble installations. During tightening, the bolt shaft, due to the square neck, does not rotate, making it convenient for fixing and installation, primarily used in areas requiring countersunk screws.
Due to the round head design of the carriage bolt, without features like cross slots or hexagonal sockets for leverage tools, it also serves as an anti-theft measure during actual connection processes.
