High-Strength Slotted Self-Tapping Thread Inserts
4.1 Product Introduction
The 302 series is the most widely used of all self-tapping thread inserts, with two slots that not only cut, but also provide a slight inward locking force.
High-Strength Slotted Self-Tapping Thread Inserts are essential fasteners for thread reinforcement and repair. The 302 series is the most versatile among all self-tapping thread inserts, featuring two precision slots that not only cut into the substrate smoothly during installation but also provide moderate inward locking force to prevent loosening.
The 303 series is a thin-walled variant of the 302 series self-tapping thread inserts. It is specially designed for plastics, light alloys and other materials with limited wall thickness. For installation in high-hardness or special environment substrates, appropriate lubrication measures can be taken to optimize the assembly process.
Features
- Creates sturdy internal threads on soft substrates, supporting repeated disassembly and maintenance without losing connection tightness.
- Effectively repairs worn or damaged internal threads, restoring the mechanical performance of the workpiece without replacing the entire component.
- Can be installed after die-casting, injection molding and other processes, simplifying the production process and improving product yield.
- Withstands high static and dynamic loads, allowing the use of smaller size self-tapping thread insertsto achieve more compact product design.
4.2 Product Parameters
|
Product name |
302/303 series High-Strength Slotted Self-Tapping |
|
Material |
Steel Zn-plated/SUS303/Customized materials |
|
Surface color |
Galvanized(yellow/blue/colorful)/Stainless steel natural |
|
Thread type |
Metric,UNC,UNF |
|
Model Number |
M2-M24/Customized specifications |
|
Function |
Thread connection,assembly fastening,damaged thread |
|
Reliability test |
Mechanical dimension detection,hardness test,48-hour |
Table of dimensions for self-tapping threaded inserts
|
Metric size Type 302 Self-Tapping Thread Insert |
|||||
|
Internal thread |
External thread
|
Length |
Guideline values for receiving hole diameter |
Minimum borehole depth for blind holes |
|
|
A |
E |
P |
B |
L |
T |
|
M2 |
4.5 |
0.5 |
6 |
4.2 to 4.3 |
8 |
|
M2.5 |
4.5 |
0.5 |
6 |
4.2 to 4.3 |
8 |
|
M3 |
5 |
0.5 |
6 |
4.7 to 4.8 |
8 |
|
M3.5 |
6 |
0.75 |
8 |
5.6 to 5.7 |
10 |
|
M4 |
6.5 |
0.75 |
8 |
6.1 to 6.2 |
10 |
|
M5 |
8 |
1 |
10 |
7.5 to 7.6 |
13 |
|
M6(a) |
9 |
1 |
12 |
8.5 to 8.6 |
15 |
|
M6 |
10 |
1.5 |
14 |
9.2 to 9.4 |
17 |
|
M8 |
12 |
1.5 |
15 |
11.2 to11.4 |
18 |
|
M10 |
14 |
1.5 |
18 |
13.2 to13.4 |
22 |
|
M12 |
16 |
1.5 |
22 |
15.2 to15.4 |
26 |
|
M14 |
18 |
1.5 |
24 |
17.2 to17.4 |
28 |
|
M16 |
20 |
1.5 |
22 |
19.2 to19.4 |
26 |
|
M18 |
22 |
1.5 |
24 |
21.2 to21.4 |
29 |
|
M20 |
26 |
1.5 |
27 |
25.2 to25.4 |
32 |
|
M22 |
26 |
1.5 |
30 |
25.2 to25.4 |
36 |
|
M24 |
30 |
1.5 |
30 |
29.2 to29.4 |
36 |
|
M27 |
34 |
1.5 |
30 |
33.2 to33.4 |
36 |
|
M30 |
36 |
1.5 |
40 |
35.2 to35.4 |
46 |
|
Metric size Type 303 Self-Tapping Thread Insert |
|||||
|
Internal thread |
External thread |
Length |
Guideline values for receiving hole diameter |
Minimum borehole depth for blind holes |
|
|
A |
E |
P |
B |
L |
T |
|
M3 |
4.5 |
0.5 |
6 |
4.2-4.3 |
8 |
|
M3.5 |
5 |
0.6 |
6 |
4.7-4.8 |
8 |
|
M4 |
6 |
0.7 |
6 |
5.6-5.7 |
8 |
|
M5 |
7 |
0.8 |
8 |
6.6-6.7 |
10 |
|
M6 |
8 |
1.0 |
10 |
7.5-7.6 |
13 |
|
M8 |
10 |
1.25 |
12 |
9.2-9.4 |
15 |
|
M10 |
12 |
1.5 |
15 |
11.2-11.4 |
18 |
|
Inch size Type 302 Self-Tapping Thread Insert |
|||||
|
Internal thread |
External thread
|
Length |
Minimum borehole depth |
||
|
UNC |
UNF |
E |
P |
B |
T |
|
4-40 |
4-48 |
5 |
0.5 |
6 |
8 |
|
6-32 |
6-40 |
6 |
0.75 |
8 |
10 |
|
8-32 |
8-36 |
6.5 |
0.75 |
8 |
10 |
|
10-24 |
10-32 |
8 |
1 |
10 |
13 |
|
1/4-20 |
1/4-28 |
10 |
1.5 |
14 |
17 |
|
5/16-18 |
5/16-24 |
12 |
1.5 |
15 |
18 |
|
3/8-16 |
3/8-24 |
14 |
1.5 |
18 |
22 |
|
7/16-14 |
7/16-20 |
16 |
1.5 |
22 |
26 |
|
1/2-13 |
1/2-20 |
18 |
1.5 |
22 |
28 |
|
5/8-11 |
5/8-18 |
20 |
1.5 |
22 |
27 |
4.3 Product Installation
Product Installation Steps
- Manual Installation
Prepare a special installation tool for self-tapping thread inserts. The tool head is a quadrilateral structure that can be connected to a manual tapping wrench. Align the insert with the pre-drilled hole, rotate the wrench clockwise to screw the insert into the substrate until it is 1mm below the surface.
- Electric Installation
Adopt AVIC-designed HRT CNC suspension electric installation machine. This equipment can realize high-efficiency and high-precision installation of self-tapping thread inserts, suitable for batch production scenarios.
Attention during installation
1.For substrates of different materials, select the corresponding pre-drilling diameter according to the parameter table. For high-hardness materials, the bottom hole diameter can be appropriately increased within the allowable range.
2.Install the insert with the slotted end facing down, keep the tool and the workpiece vertical during installation. Align the bottom hole accurately in the first 1-2 pitches of installation, and do not tilt. If tilting is found, stop operation immediately and readjust the position.
3.After the insert is screwed into 1/3-1/2 of the depth, do not reverse and re-start the installation to avoid thread slipping.
4.After assembly, ensure that the top of the self-tapping thread insert is at least 1mm lower than the surface of the part to ensure connection stability.