Example aspects of a stent spring for a stent, a stent for repairing a pipe, and a method for repairing a pipe are disclosed. The stent spring for a stent can comprise a plurality of minor springs connected in a series around a circumference of the stent spring, each of the minor springs defining a first leg and a second leg; and a spring constrictor engaged with each of the minor springs, each of the spring constrictors movable between a first position, wherein the corresponding minor spring defines a first maximum width, and a second position, wherein the corresponding minor spring defines a second maximum width that is greater than the first maximum width.