Welding process for tower door frame

Abstract

The invention relates to a welding process for a tower door frame. The welding process comprises the following specific steps of S1, coiling a tower drum; S2, forming a hole in the tower drum; S3, beveling a door frame hole; S4, positioning a door frame; S5, performing spot welding positioning; S6, preheating a joint; S7, selecting a welding wire; and S8, welding an inner bevel and an outer bevel.The welding process has the advantages that a second cone part is arranged on the outer edge of the door frame, so that the horizontal accuracy and positioning-embedding size of the door frame embedded in the tower drum are ensured; transverse concentration of the welding stress is avoided; and the reduction of the stress level and stress balance are ensured.

Description

Technical field: [0001] The invention relates to the field of wind power generation towers, in particular to a welding process for a door frame of a tower. Background technique: [0002] The offshore wind power tower is the tower pole of wind power generation, which mainly plays a supporting role in the wind power generation unit and absorbs the vibration of the unit at the same time. The tower body of the wind power tower is welded vertically by several tower sections, and the door frame is welded and fixed on the tower. Both are fixed. [0003] In the welding process of the tower door frame and the tower tube, there are the following technical problems: [0004] 1. Patent No. 201711470055.9 discloses in the manufacturing method of the tower section, the tower section, the tower and the wind power generation unit, respectively opening gaps in the first tube section and the second tube section, and the door frame is embedded in the opening composed of the two gaps And fix...

AI Technical Summary

Problems solved by technology

[0004] 1. Patent No. 201711470055.9 discloses in the manufacturing method of the tower section, the tower section, the tower and the wind power generation unit, respectively opening gaps in the first tube section and the second tube section, and the door frame is embedded in the opening composed of the two gaps And fixed by welding, there are certain dimensional deviations in opening the gaps, the dimensional accuracy of the door frame hole is low, and the fit between the opening and the door frame is low. When the door frame is embedded in the opening, the horizontal accuracy of the embedding cannot be guaranteed and the embedded size cannot be positioned;

[0005] 2. The stress during the welding of the door frame and the tower tube segment is the most prominent problem in the welding process of the tower door frame. When the existing door frame is welded with the tower tube, bevels are respectively provided on the inside and outside of the door frame hole of the tower tube, such as image 3 As shown, the welding direction is inclined towards the gap between the groove and the door frame, and the angle of the inclined welding cannot be precisely controlled, so the welding quality cannot be controlled. At the same time, if image 3 As shown, the welding stress is concentrated horizontally on the outer edge of the door frame and the bevel of the tower, so that the weld surface between the door frame and the door frame hole accumulates stress, and welding defects such as welding cracks appear. To ensure that the welding is firm, the groove angle is general When it is set to 45°, the stress concentration is biased toward the door frame, and the stress level of the door frame is high;

[0006] 3. When welding between the door frame and the door frame hole of the tower, the operator needs to hold the drying gun to preheat alternately. The preheating temperature reaches 100°C, so as to relatively reduce the stress during welding. If the preheating temperature does not meet the requirements, it will cause During the welding process, the inside and surface of the weld between the door frame and the door frame hole produces a large residual stress, and weld cracks appear on the surface of the weld after welding, which brings troubles for repairing the product and the risk of fracture of the door frame weld in use. There is a phenomenon of cooling while preheating during the alternate preheating process of the hand-held drying gun. The energy utilization rate is only about 20%, and the preheating efficiency is low. The uniformity and efficiency of preheating cannot be guaranteed. Therefore, the subsequent welding stress concentration have a greater impact

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