Well Testing Downhole Drill Stem Testing(DST) Tools
A properly conducted well test is a temporary completion of a well to acquire dynamic rate through time, pressure, and fluid property data. The well test often indicates how the well will perform when it is subjected to various flow conditions. An analysis is usually performed on the data to determine reservoir parameters and
characteristics. Production decline may be predicted using these parameters and characteristics. The production decline can be used to predict cash flow. Once cash flow is known, improved drilling, completion, and production decisions can be made on this well and other wells in the field. Well test objectives can be classified as short term or long term.
• Short-term well test objectives typically involve gathering and analyzing sufficient well data to obtain a description of the reservoir system in the vicinity of the wellbore.
• Long-term well test objectives focus on gathering and analyzing data to obtain a complete description of the reservoir. The test time required to satisfy the test objectives varies for each reservoir. These test times are directly related to the testing costs and data needed.
The well testing and sampling operation is typically accomplished with an assortment of test tools. The basic downhole test tools required for a well test include:
• Reversing valve
• Tester valve
• Samplers
• Gauges (pressure and temperature recorders)
• Packer
• Tubing conveyed perforating guns
Hydraulic Jar
The Hydraulic Jar is a straight-pull operated jar with a closed hydraulic system and a unique balance piston used to equalize oil pressure with tubing pressure. The hydraulic jar is also able to transmit torque to the right at any position along full stroke and helps free a stuck tool or tool string by resisting a pull on the workstring.
Features
* Design of the hydraulic system ensures long life with little maintenance.
* Rig time is reduced.
* Jar can be re-cocked rapidly.
* Jar time delay is adjustable.
* Amount of pull to trip the jar can be varied within the limits of the time-delay system.
Specification
| OD/In |
Working pressure/Mpa |
Service Environment |
Working temperautre |
connection |
8"
3 7/8"
3 1/8" |
70/105 |
Mud, Crude oil, Natural gas with H2S and acid |
-29ºC- +204ºC |
EUE/IF/CAS |
Audited Supplier 
Audited Supplier 
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