Jining Donghong Machinery Co., Ltd

QJZ Mechanical Drilling Jar

Introduction:

QJz mechanical drilling jar is fully mechanically operated and is an integrated unit that provides both up and down jarring operation. As part of the drill stem, it is used to free drill string components from sticking incidents and increase drilling efficiency by providing instantaneous jarring action without delay. The mechanical drilling jar relies on a trip and friction sleeve to activate jarring action. The jar is designed to trigger the jarring action when a sufficient amount of force (jar trip load) is applied to the jar in either up or down direction.

Working principle

●up Jarring

Up Jarring is achieved by pulling the drill string until it reaches the jar trip   load. The jar trip load will cause the internal spring unit to deform, allowing   the trip sleeve to engage the friction sleeve. When this happens, the mandrel is suddenly freed to release the jarring force. To reset the jar, remove the pull load by lowering the drill string.

●Down Jarring

There is another set of internal spring sleeve located at the top of the slips. Down Jarring is achieved by lowering(pushing) the drill string until it reaches the jar trip load. The jar trip load will cause the internal spring unit to deform, allowing the trip sleeve to engage the friction sleeve. When this happens, the mandrel is suddenly freed to release the jarring force. To reset the jar, remove the downward load by pulling the drill string.

Available model:

  QJZ95   QJZ108   QJZ121   QJZ159   QJZ165   QJZ178   QJZ203   QJZ229

Connection type:

  NC26   NC31   NC38   NC46   NC50   NC50   6 5/8 Reg   7 5/8 Reg

Specifications - QJZ Mechanical Drilling Jar

1   QJZ Mechanical Drilling Jar   QJZ95   95   28   6000   200   200   200   100   600   4   NC26   3398   33   360

  2   QJZ Mechanical Drilling Jar   QJZ108   108   38   6000   200   200   300   150   800   8   NC31   3370   44   432

  3   QJZ Mechanical Drilling Jar   QJZ121   121   51   6000   200   200   430   300   1400   10   NC38   3347   50   573

  4   QJZ Mechanical Drilling Jar   QJZ159   159   57   6970   142   172   620   360   2200   15   NC46   3456   100   1150

  5   QJZ Mechanical Drilling Jar   QJZ165   165   57   6970   142   172   620   360   2200   15   NC50   3456   100   1240

  6   QJZ Mechanical Drilling Jar   QJZ178   178   57   6468   149   168   700   420   2200   15   NC50   3476   133   1350

  7   QJZ Mechanical Drilling Jar   QJZ203   203   71.4   7310   145   178   800   450   2500   20   6 5/8 Reg   3048   176   1780

  8   QJZ Mechanical Drilling Jar   QJZ229   229   76.2   7820   203   203   800   450   3000   25   7 5/8 Reg   2580   227   2430