When the American Petroleum Institute (API) established standardized
crush-testing procedures (API RP-56 1983), the committee indicated that the
test results should "provide indications of the stress level where proppant
crushing is excessive and the maximum stress to which the proppant material
should be subjected." However, over time, many have forgotten not only how the
test is conducted, but also its original intent. As such, many now
unintentionally misapply the results of crush testing as they select proppants
for their fracture designs.
This paper will review the top 10 myths associated with crush testing and
its interpretation, addressing such common questions as
- Do standard test conditions (high proppant concentration and low
temperature) provide realistic predictions of proppant performance?
- Should proppant be tested wet or dry?
- Does the loading procedure affect crush?
- What happens if proppant is not distributed uniformly in a fracture?Do all
proppants fail in the same manner?
- Are all proppant types equally damaged by 5% crush?
- How can the industry misuse the test to report "superior" results?
Readers of this paper will be armed with a better understanding of how crush
testing is performed, how crush results can be misapplied, and the correct use
of crush-test results. In addition, the authors will present an alternative
methodology for evaluating proppant that incorporates all of the benefits
gained from crush testing, but avoids the common pitfalls. Armed with this
information readers can improve the design of fracture treatments, thereby
achieving increased production rates and superior economic returns.
© 2010. Society of Petroleum Engineers
View full textPDF
- Original manuscript received:
23 October 2009
- Meeting paper published:
20 January 2009
- Revised manuscript received:
18 March 2010
- Manuscript approved:
19 March 2010
- Published online:
22 July 2010
- Version of record:
11 August 2010