دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: 1. a derrick or crane shaped like the letter A and used to handle heavy loads. 2. an A-shaped openwork structure that is the stationary and supporting component of the mast of a jackknife rig and to which the mast is anchored when it is in an upright or drilling position. 3. the uppermost section of a standard derrick, shaped like the letter A and used as a support in lifting objects such as the crown block to the water table.

n: A kind of "A" frame gin pole, used to elevate heavy object.

n: an A-frame that booms out 5 to 10 feet over the side of a barge. It has a cable or chain that is lowered to pick up pipeline. A diver attaches the pipeline to the line and it is reeled in on the davit.

n: I. a block that can be opened to receive wire rope or wireline. 2. a block that is suited for a single sheave and is used for pulling horizontally on an A-frame mast.