The Hydra-Jar AP* double-acting hydraulic drilling jar is used to amplify the force applied at surface in order to free stuck drillstem components during drilling and fishing operations. The direction of jarring can be both up and down. The jar uses a unique temperature-compensation process to provide consistent impact, blow after blow, and high-temperature seals that make it suitable for hostile drilling conditions. In most applications, the tool should be run in conjunction with the Accelerator AP* impact tool to increase the impact while protecting the drillstring and surface equipment from shock. The jars are serviced and inspected at our service centers to ensure proper downhole operation. Do not place rig tongs on service connections or on the chromed area of the mandrel. Do not remove vent or fill plugs; mud or grease running out of vent ports is not detrimental to the operation of the tool. Operating instructions Make up the lift sub and hoist the tool in the elevator. Remove the safety clamp just prior to lowering the tool into the hole. Working string weight above the jar = drag + string weight from drilling jar to surface. Drag = weight indicator reading up – weight indicator reading down. Jarring up: - Establish the “jar load up (overpull)” to be applied, subject to the maximum detent working load shown in the table of specifications. Jar load up = final weight indicator reading up, before impact – working string weight above the jar. - Apply pull to the drillstring as per the established final weight indicator reading and wait for the impact. The weight indicator will display a small loss just before impact, corresponding to the retraction of the drillstring. There should be a clear change in the reading after impact. - To repeat the operation, slack off until the indicator reads 10,000 to 15,000 lbf lower than the “working load down” and immediately apply the previous jar load up again. Jarring down: - Select the “jar load down (slack-off),” subject to ● the maximum detent working load shown in the specifications table and - the weight of the drill collars or Hevi-Wate* transition drillpipe just above the Hydra-Jar AP jar, whichever is less. Jar load down = working string weight above the jar – final weight indicator reading down, before impact. - Slack off per the established final weight indicator reading, and wait for impact. - To repeat the operation, pull up until the weight indicator reads 10,000 to 15,000 lbf higher than it did before impact, and immediately slack off to the previously selected “jar load down” again. - Down-jar impacts may not be transmitted through shock tools run in the lower drilling assembly. When jarring down with a small number of drill collars or Hevi-Wate drillpipe on top of the jar, select a load that will not buckle the drillpipe run above the jar. Adequate weight just above the jar provides optimal impact for down-jarring. The mud pump should be shut down or slowed before down-jarring operations begin.
|Normal Temp & High Temp