LockJar
Wireline Technology

System Benefits

Versatility by Design:

Hydraulic time delay allows for use of maximum force available through surface pull to create an impact. This gives a service engineer complete use of new wireline technology (high strength cable and solid weak points) when trying to free a stuck tool string and is critical in situations where stuck conditions are severe. Mechanical tools can use a max force equal to its highest lock setting when creating an impact. Often this value is considerably less than maximum force available to create an impact.

Reliability:

Internal parts, including the jar mechanism and conductive path, are sealed and segregated from the wellbore. This minimizes wear on critical parts and increases tool reliability both as a data transmitter and power supply. Multiple jobs can be completed before tear down and redress is required. This attribute is key especially when tools are being used in remote or international locations.

Ease of Use:

The LockJar system arrives at the wellsite ready to run and does not require the presence of an EVANS service engineer. Logging personnel can be instructed on tool operation and lock adjustment very quickly. If requested by customer, Evans personnel are available for onsite supervision.

Proven Design:

Since its commercial introduction in the last quarter of 2002, the LockJar system has routinely freed stuck tool strings in areas where fishing jobs are common and unproductive rig time is prohibitive. On numerous occasions the jar was activated several times in more than one location in a wellbore and in each case logging operations were completed after the tool string was freed. On one job in the Gulf of Mexico the LockJar was activated a total of 20 times in six different intervals, enabling the logging operation to be completed.

Favorable Cost to Benefit Ratio:

The cost of including LockJar technology in the logging string is small compared to the enormous cost of a fishing job, unproductive rig time, or a lost tool string.

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