High frequency welding fin tube production method
The set fin process is to pre-process a batch of individual fins by punching, and then manually or mechanically, according to a certain height (wing distance), the fins are placed on the outer surface of the tube by interference. It is the earliest method of processing finned tubes. Due to the simple process and low technical requirements, the equipment used is inexpensive and easy to maintain, so many factories are still in use. This process is a labor-intensive process solution that is suitable for the capital and technical conditions of small or medium-sized enterprises.
The manual method is called a manual suit. It uses tools to rely on human strength to push the fins one by one. In this method, since the pressing force of the fin is limited, the interference of the set is small, and the fin is prone to looseness.
The mechanical set fins are made on a fin set machine. Since the fin press-in is caused by mechanical impact or liquid pressure, the press-in force is large, so that a large interference can be used. The joint strength between the fin and the tube is high and it is not easy to loosen. The mechanical transmission set machine has high productivity, but the noise is high, the safety is poor, and the labor conditions of the workers are not good. Although the above problems are not present in the hydraulic transmission, the equipment is more expensive, the technical requirements for the maintenance personnel are higher, and the productivity is lower.
The inlaid spiral finned tube is a spiral groove of a certain width and depth pre-machined on the steel pipe, and then the steel strip is embedded on the steel pipe on the lathe. During the winding process, due to a certain pre-tightening force, the steel strip will be tightly placed in the spiral groove, thereby ensuring a certain contact area between the steel strip and the steel tube. In order to prevent the steel strip from rebounding, both ends of the steel strip are welded to the steel pipe. In order to facilitate the setting, there should be a certain backlash between the steel strip and the spiral groove. If the backlash is too small and an interference is formed, the inlaying process is difficult to proceed smoothly. In addition, the entangled steel strip always has a certain rebound, which results in a poor joint between the steel strip and the spiral groove bottom surface. Inlaid fins can be carried out on general-purpose equipment at a low cost, but the process is complicated and the production efficiency is low.
