The present invention is a dilation tube extending in the front-rear direction and including a tubular body portion and a puncture portion, the puncture portion is disposed at the front end of the tubular body portion, and the puncture portion includes a first rigid layer from front to back in the front-rear direction. a second rigid layer and a third rigid layer, the third rigid layer connecting the front end of the tubular body portion, and sequentially connecting the second and first rigid layers, and the third rigid layer has a hardness greater than the second rigid layer The hardness of the second rigid layer is greater than the hardness of the first rigid layer. Since the hardness of the rigid layer of the present invention is gradually strengthened from front to back, the strength of the puncture can be concentrated during the puncture, and the hardness is The lower first rigid layer reduces the likelihood of stabbing blood vessels during the end puncture.本創作係一種擴張管，擴張管沿前後方向延伸，並包含有管體部及穿刺部，穿刺部設置於管體部的前端，並穿刺部沿前後方向由前至後包含有一第一剛性層、一第二剛性層及一第三剛性層，第三剛性層連接管體部的前端，並依序向前連接第二及第一剛性層，且第三剛性層的硬度大於第二剛性層的硬度，第二剛性層的硬度大於第一剛性層的硬度，由於本創作的剛性層之硬度係由前至後逐漸加強，使本創作在穿刺時，可較為集中其穿刺的力量，且硬度較低的第一剛性層可降低其端部穿刺過程中刺傷血管的可能。
