Pressure Testing

Hydrostatic testing (pressure testing) is an essential design validation stage of downhole tools. We offer two testing options to the industry: Ultra high pressure testing chamber and a highly configurable lab for functional testing downhole hydraulic components.

Ultra High Pressure Testing Chamber

Pressures downhole can be as high as 35,000 psi (241 MPa) which requires significant engineering efforts to design downhole tools capable of withstanding such demanding sealing and structural requirements. Pressure testing applies external hydrostatic forces on the tool to validate the seals and structural integrity.

Pressure pit: Vertical subsurface pressure testing chamber with 35,000 psi. Incorporates optional feed throughs for running wires and fluid capillary tubing into the test chamber.

Criteria driving end users' decisions for pressure testing:

  • Pressure testing new designs – The oil and gas downhole industry typically tests all new downhole tool designs to validate the new design's seal integrity and structural integrity.
  • Pressure testing for manufacturing – Once a new design has been verified, a decision is made as to whether all future builds of the tools are tested as an inspection operation in the manufacturing process. The decision is based on the combination of the likelihood of a downhole failure and the severity of the consequences of the failure.

Functional Testing Lab for Downhole Hydraulic Components, highly configurable

Hydraulics are used in downhole tools for multiple purposes: mechanical movement, triggering valve actuations, flow management and pumping. Engineering teams designing these tools use functional testing for design validation and design refinement. Setting up functional testing requires equipment (pumps, meters, data recording, lifting equipment…), hardware (tubing, fittings, valves….), experienced testing staff which are expensive and time intensive to build. We offer on-demand testing which reduces testing project costs, reduces project timeline and we share invaluable best practices.

Captured measurements of test inputs and outputs with high speed data acquisition:

Testing Pressure Icon
Pressure
Testing Flow Icon
Flow
Testing Volume Icon
Volume
Testing Force Icon
Mechanical Force
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Mechanical movement distance: linear and rotational
Testing Pressure Icon
Mechanical movement speed: linear and rotational

Examples of testing and data capture:

  • Fluid slippage for seal-less downhole pumps and valves: Quantifying slippage flow rate at various pressure differentials, gap clearances, linear length of gap and flow path designs
  • Events such as Valve Actuation, Disk Rupture, Pin Shear: Capturing variations of the input triggering event and consequence to the output results
    • Hydraulic: pressures, flow rates, volumes
    • Mechanical: Distances, speeds, forces

Equipment and facilities

  • 60,000 psi pumping
  • Multiple pumps for simultaneously applying and recording various pressures and flow rates
  • Accumulators for high volume, constant volume flow
  • Vertical testing up to 28 ft (8.5 m). Unlimited horizontal length
  • High speed data acquisition
  • Experienced staff in designing tests, executing tests and interpreting test results
  • On site machine shop for quick planned and unplanned modifications
  • Large inventory of seals, fittings, valves, high pressure tubing, high volume hoses (can be easily underappreciated by someone without significant testing experience).
Test failure broken pipe
Test result of a dramatic failure in material with low elongation properties. Although the specimen failed unexpectedly in testing, the specimen owner was grateful the failure did not occur in a customer's well.
Open hole wireline logging tool
Loading an open hole wireline logging tool into the pressure pit for testing
Seal heads
Example of the 300+ seal heads National K Works has in inventory to support the myriad of tool joints within the industry.
Styrofoam cup
Styrofoam cup comparison, before and after 20,000 psi (138MPa)
Pressure dial
61,000 psi (421 MPa) burst pressure applied to hydroform and autofrettage
Bottle Boring
Typical failure mode of a collapsed housing without an internal "filler bar".
Collapsed internal key way
Unusual failure of a collapsed internal key way. Failure was caused by the lack of an intentional fluid entry point into the cavity under the keyway which is commonly a small diameter radial hole or a machined notch on the face of the housing. Without a fluid entry point, the fluid could not enter under the internal keyway which created a differential pressure that exceeded the material's yield point. Surprisingly, the faces between housing and pressure testing head created a metal to metal seal.
Contact us now to learn more!