دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

an “extra” string in a casing design that can be used in the event of failure to get an upper string to the correct depth.

n: 1. a string of pipe used to case open hole below existing casing. A liner extends from the setting depth up into another string of casing, usually overlapping about 100 feet (30.5 metres) above the lower end of the intermediate or the oil string. Liners are nearly always suspended from the upper string by a hanger device. 2. a relatively short length of pipe with holes or slots that is placed opposite a producing formation. Usually, such liners are wrapped with specially shaped wire that is designed to prevent the entry of loose sand into the well as it is produced. They are also often used with a gravel pack. 3. in jet perforation guns, a conically shaped metallic piece that is part of a shaped charge. It increases the efficiency of the charge by increasing the penetrating ability of the jet. 4. a replaceable tube that fits inside the cylinder of an engine or a pump. See cylinder linel:

n: a string of the casing that only extends back to inside the previous casing shoe and not back to surface as other casing strings do.

n: an accessory to a fishing tool, placed above it. If the tool cannot be disengaged from the fish, the safety joint permits easy disengagement of the string of pipe above the safety joint Thus, part of the safety joint and the tool attached to the fish remain in the hole and become part of the fish.

n: a toolthat is often run just above a fishing tool.if the fishing tool has gripped the fish but can not pull it free, the safty jiont will allow the string to disengage by turning it from surface.

a joint above a piece of equipment that is designed to fail and allow recovery of the upper string.

a joint above a piece of equipment that is designed to fail and allow recovery of the upper string.

n: any part of the drill stem, tubing string, or casing string that lies in the upper part of the borehole.