Hydraulic Bolting

Tightening up nuts/bolts on a Blowout Preventer Spool (BOP) They are used in the oilfield to connect the BOP to wellhead. This is a much safer and more accurate method then swinging a hammer to tighten up bolts. These bolts went on and tightened up fairly easy as opposed to old studs and nuts that are rusted out and stripped. A 4 bolt method ensures that the BOP spool has ceded properly. Going back 1 and up 2 also ensures that the bolt before has been torqued enough. You can use the star pattern method but one has to label each nut to remember the pattern which can be time consuming. Oilfield terminology. Nipple up means to tighten the studs/nuts up. Nipple down means to loosen the studs/nuts up. This BOP spool can be repaired by a certified welder and re-inspected.