Method for increasing number of tapping threads

Abstract

The invention provides a method for increasing the number of tapping threads, and belongs to the field of assembly machining. The invention provides a method for increasing the number of tapping threads, which comprises the following steps of: carrying out hot melting stretching on a to-be-tapped part by using a hot melting drill in a direction vertical to the to-be-tapped part, and then tapping. According to the invention, the to-be-tapped part is stretched, so that the depth of the to-be-tapped part is increased, the number of tapped threads is increased, and the torsion of the tapped threads is improved.

Description

Technical Field

[0001] The invention relates to the field of assembly processing, and in particular to a method for increasing the number of tapping threads. Background Art

[0002] The pipes on the electric vehicle frame can support and strengthen the vehicle body, and are also the base for assembling parts through screws. Although thin pipes can meet the strength requirements, the number of threads obtained after tapping is limited due to thickness restrictions, and thus cannot meet the torque requirements of the screws. For example, a 2mm thick pipe can only tap two threads when tapping M6 threads (pitch 1mm), while the standard torque of M6 screws is 8~10N, and the torque of two threads can only reach 4~6N. Summary of the invention

[0003] The purpose of the present invention is to provide a method for increasing the number of tapping threads. The method provided by the present invention increases the number of tapping threads and improves the torque of the tapping threads.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The present invention provides a method for increasing the number of tapping threads, comprising the following steps:

[0006] In a direction perpendicular to the part to be tapped, the part to be tapped is subjected to hot melt stretching by a hot melt drill, and then tapping is performed.

[0007] Preferably, when the wall thickness of the portion to be tapped is 1.8-2 mm, the depth of the portion to be tapped after hot-melt stretching is ≥3.5 mm.

[0008] Preferably, the number of threads produced by the tapping is ≥3.

[0009] Preferably, the rotation speed of the hot melt drill is 1750-2000 r / min, and the travel speed of the hot melt drill is 170-185 mm / min.

[0010] Preferably, the temperature of the hot melt stretching is 550-600°C.

[0011] Preferably, the melt drill is driven by a high-speed bench drill.

[0012] Preferably, the melt drill has a tungsten steel conical head.

[0013] Preferably, the portion to be tapped includes a portion to be tapped of a plate or a portion to be tapped of a pipe.

[0014] The present invention provides a method for increasing the number of tapping threads, comprising the following steps: hot-melt stretching the portion to be tapped with a hot melt drill in a direction perpendicular to the portion to be tapped, and then tapping. The present invention increases the depth of the portion to be tapped by stretching the portion to be tapped, thereby increasing the number of threads after tapping and improving the torque of the tapping threads. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a cross-sectional view of a pipe according to an embodiment of the present invention;

[0016] Figure 2 A hot melt drill according to an embodiment of the present invention;

[0017] Figure 3 A tap used in an embodiment of the present invention;

[0018] Figure 4 This is a cross-sectional view of the pipe after tapping in Example 1. DETAILED DESCRIPTION

[0019] The present invention provides a method for increasing the number of tapping threads, comprising the following steps:

[0020] In a direction perpendicular to the part to be tapped, the part to be tapped is subjected to hot melt stretching by a hot melt drill, and then tapping is performed.

[0021] In the present invention, the temperature of the hot melt stretching is preferably 550-600°C, the rotation speed of the hot melt drill is preferably 1700-2000 r / min, and the travel speed of the hot melt drill is preferably 170-185 mm / min. During the hot melt stretching process, the part to be tapped is melted due to the high temperature generated by friction, and then the part to be tapped is stretched by the movement of the hot melt drill, and the part to be tapped is also heat treated during the hot melt stretching to improve the hardness of the part to be tapped.

[0022] In the present invention, the melt drill is preferably driven by a high-speed bench drill; the melt drill is preferably a tungsten steel conical head.

[0023] In the present invention, when the wall thickness of the portion to be tapped is 1.8-2 mm, after hot melt stretching, the portion to be tapped after hot melt stretching is preferably ≥3.5 mm; when the tapped thread is M6, the number of threads generated by the tapping is ≥3.

[0024] In the present invention, the portion to be tapped preferably includes a portion to be tapped of a plate or a portion to be tapped of a pipe.

[0025] The present invention has no special limitation on the tapping, and any solution well known to those skilled in the art may be used.

[0026] The method for increasing the number of tapping threads provided by the present invention is described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0027] The cross-sectional view of the pipe of the embodiment of the present invention is as follows Figure 1 As shown;

[0028] The hot melt drill of the embodiment of the present invention is as follows Figure 2 As shown;

[0029] The tap of the embodiment of the present invention is as follows Figure 3 shown.

[0030] Example 1

[0031] A high-speed bench drill (speed 1800 / min, pressing speed 180mm / min) drives the tungsten steel conical head to perform hot melt stretching on the 2mm thick pipe to be tapped (the temperature generated by friction is 550-600℃), stretching the depth of the tapped part to 4-5mm, and then use a tap to tap the M6 ​​thread. The number of threads reaches 4-5, the torque value reaches 16-20N, and the standard value of 8-10N.

[0032] The cross-section of the pipe after tapping is as follows: Figure 4 shown.

[0033] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for increasing the number of tapping threads, characterized in that: The following steps are involved: In a direction perpendicular to the part to be tapped, the part to be tapped is subjected to hot melt stretching by a hot melt drill, and then tapping is performed.

2. The method according to claim 1, characterized in that When the wall thickness of the portion to be tapped is 1.8-2 mm, the depth of the portion to be tapped after hot-melt stretching is ≥3.5 mm.

3. The method according to claim 2, characterized in that The number of threads produced by the tapping is ≥3.

4. The method according to claim 1, characterized in that: The rotation speed of the hot melt drill is 1750-2000 r / min, and the travel speed of the hot melt drill is 170-185 mm / min.

5. The method according to claim 1 or 4, characterized in that: The temperature of the hot melt stretching is 550-600°C.

6. The method according to claim 1 or 4, characterized in that: The hot melt drill is driven by a high-speed bench drill.

7. The method according to claim 1, characterized in that The hot melt drill has a tungsten steel conical head.

8. The method according to claim 1, characterized in that The portion to be tapped includes a portion to be tapped of a plate or a portion to be tapped of a pipe.

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