Double H Fin Tube  

DOUBLE H FIN TUBE 1.Welding strength and stability 1.1Pull-off test: more than 200MPa or partial tear of steel pipe 1.2Weld width: greater than fin thickness, ie weld rate >98% 1.3Welding strength stability: The welding specimen of the first piece of each class meets the requirements of 2.1 or 2.2. 1.4Weld resistance bending test: The fins are bent 20 degrees to the left and right. 2 times to the left. The welds are crack-free. 1.5Hammer test: Strike the upper part of the fin parallel to the steel pipe until the fins fall off. The fin itself must not break. 1.6If the test fails, the annealing function must be enabled. 2.Heat affected zone 2.1Microscope with micro hardness tester 2.2The depth of the heat affected zone of the steel pipe is less than 0.5mm 3.Product size accuracy 3.1Full length of wing fragments -1mm ~ +1mm Segmental motion accuracy -0.5mm ~ +0.5mm 3.2Sheet spacing -0.2mm ~…