Continuous process for manufacturing a polyolefin resin in at least two reactors in which in a first polymerization reactor, an olefin is polymerized continuously in the presence of a catalyst and a diluent to produce a first suspension comprising the diluent and polyolefin particles. The methods may include forming a resist layer on a substrate, the resist layer including a first region, a second region surrounding the first region, and a third region surrounding the second region. The plug and seat are released from the sub when one or more dogs releasably positioning the seat in the mandrel bore disengages from the seat due to a bleed off of fluid pressure in the well bore.