There are two main types of high frequency induction welding, contact welding and induction welding. Induction welding is a non-contact welding method using coils. Contact welding is the use of conductive materials to directly lead high-frequency current to the welding area of steel pipes, and then weld the materials after heating.
Application environment of high-frequency welding contact materials
The working environment of the high-frequency contact welding head is very harsh, mainly as follows:
1) water, emulsion, high temperature, heat, smoke, corrosive gas or liquid can be seen by naked eyes in most environments;
2) Carrying high-frequency AC current and voltage, the common current frequency is 200 kHz-800 kHz, and the current varies from several hundred amperes to several thousand amperes according to the power of the equipment;
3) In production, the contacts of the equipment work under a certain pressure, generally ranging from 2 to 4 bar;
4) The equipment runs continuously on line, and the contact constantly bears the sliding friction of the welded material below under pressure;
5) Because the environment where the contact is located is dirty, and the oxide generated in the process of high temperature friction of the contact is heated seriously, the oxide impurities will be ignited and arc drawn under the action of high current;
6) When the welded object below is uneven, the contact resistance at the contact will change greatly, and electric sparks of different degrees will appear at the contact;
In addition to the above environmental conditions, the working environment of welding contacts will be severely challenged due to the pressing force of the operating contacts of field operators, the resilience of the welded materials, the hardness of the welded materials, the surface friction force and so on.
Characteristics requirements of high frequency welding contact material
Due to the working requirements of the contact welding contacts and the working environment limitation of the welding head, special characteristic requirements are put forward for the materials of the contact welding head. As a contact welding head, its materials must have the performance in line with practical application in the following aspects:
1) conductivity, because the contact carries a relatively large current-carrying requirements, contact materials should have high conductivity to reduce contact resistance, low secondary emission and light emission to reduce arc current and arc time, so materials must have high conductivity;
2) Heat conduction ability, because the contact carries large current, its own temperature is high, so it must have certain heat dissipation ability and high heat conduction ability so that the heat generated by arc or Joule heat source can be transferred to the contact base as soon as possible;
3) Strength, because the contact works under a certain pressure, it is also necessary to consider the strength of the material;
4) Wear resistance, because the contact is constantly rubbing against the surface of the welded object during work, the contact material needs to have considerable wear resistance;
5) Hardness is also one of the characteristics to be considered. Under a certain contact pressure, the smaller hardness can increase the contact area, reduce the contact resistance, and reduce the tendency of contact heating and static welding during static contact. Higher hardness can reduce welding area and improve mechanical wear resistance;
How to choose contact materials ?
The selection of contact materials mainly depends on the cost, product surface requirements, product welding area size requirements and product material characteristics.
1. general oxygen-free copper or forged oxygen-free copper is adopted when selecting from general materials, and the conductivity of copper reaches 99%;
2. Choose alloy copper, such as tungsten-copper alloy, pick chromium copper, tungsten carbide alloy copper, etc.;
3. Other alloys, such as titanium alloys; Choosing alloy materials, the specific copper content and alloy content need to be determined according to the actual field application, considering the conductivity, wear resistance, product surface requirements, etc.
4.The content of the article comes from other placesThere are two main types of high frequency induction welding, contact welding and induction welding. Induction welding is a non-contact welding method using coils. Contact welding is the use of conductive materials to directly lead high-frequency current to the welding area of steel pipes, and then weld the materials after heating.
5.Application environment of high-frequency welding contact materials
6.The working environment of the high-frequency contact welding head is very harsh, mainly as follows:
7. water, emulsion, high temperature, heat, smoke, corrosive gas or liquid can be seen by naked eyes in most environments;
8. Carrying high-frequency AC current and voltage, the common current frequency is 200 kHz-800 kHz, and the current varies from several hundred amperes to several thousand amperes according to the power of the equipment;
9. In production, the contacts of the equipment work under a certain pressure, generally ranging from 2 to 4 bar;
10. The equipment runs continuously on line, and the contact constantly bears the sliding friction of the welded material below under pressure;
11.Because the environment where the contact is located is dirty, and the oxide generated in the process of high temperature friction of the contact is heated seriously, the oxide impurities will be ignited and arc drawn under the action of high current;
12. When the welded object below is uneven, the contact resistance at the contact will change greatly, and electric sparks of different degrees will appear at the contact;
In addition to the above environmental conditions, the working environment of welding contacts will be severely challenged due to the pressing force of the operating contacts of field operators, the resilience of the welded materials, the hardness of the welded materials, the surface friction force and so on.
Post time: May-26-2021