用一个内径略大于试管,比试管稍长些的瓷筒,在其两头加装箍铁,将电炉上的800w电阻丝环绕瓷筒上,电阻丝的两个端头分别固定在铁箍的螺杆上,插头导线的两个端头分别绕在铁箍螺杆上。用螺帽旋紧。万能夹夹紧瓷筒上端,固定在方座支架上。使用时 Use a porcelain tube with an inner diameter slightly larger than the test tube and slightly longer than the test tube, install hoop iron on both ends, surround the 800w resistance wire on the electric furnace around the porcelain tube, and fix the two ends of the resistance wire on the iron hoop screw respectively. In the above, the two ends of the plug wire are respectively wound on the hoop screw. Tighten with a nut. The universal clamp grips the upper end of the porcelain cylinder and is fixed on the square bracket. when using it