Abstract: For the operation line of spiral SAW pipe with strip coil without edge planed or milled, tube quality considerably depends on whether its circular shear blade is properly arranged or not. Described here in the article are the cantilever type circular shear blade and its loading conditions, focusing on how the arrangement and adjustment of the shear blade itself influence the tube quality. It is concluded that proper arrangement and adjustment of the cantilever type circular shear blade can not only produce good strip edge profile to improve tube quality, but also tremendously extend the service span of the shear blade so as to bring about more economic benefit to the producer.