Ed: This halacha seems to be slightly tangential to the title of the siman, dealing instead with the repair of a broken vessel:
83) When vessels made of different sections inserted into one another became separated, if they were usually joined loosely, it is permissible to put them back. However, if they were usually joined tightly (esp. with screws etc.), it is forbidden to put them back even loosely. In contrast, it is permissible to remove jar and bottle covers and to put them back on (i.e. even though they screw on and off), since they are not made to remain there, but rather to be opened and closed constantly.
Ed: If I may suggest a practical application of this halacha - I quote from The 39 Melachos by Rabbi Ribiat, Vol. IV, pp. 1140-1411: “An eyeglass lens that popped out may not be snapped back into place, because doing so is an effective permanent repair of the eyeglasses, and would therefore be makeh b’patish (i.e. the malacha “the final hammer blow”). If the lens will require proper installation by a professional afterward, then, while temporarily snapping the lens in place might not be a Torah-forbidden melacha, it would nevertheless be rabbinically prohibited. Installing the lens is forbidden even if the frame has widened (to the extent that the lens fits only loosely), because this could lead one to tighten the frame inadvertently on Shabbos, thereby transgressing makeh b’patish. However, if the frame of the lens is itself broken, the lens may be temporarily tied to the broken frame with a bow-knot or fastened together by rubber-bands etc., because: a) this is an obviously temporary repair, and b) this could not lead to tightening or to any permanent repair, because the frame is irreparable.”