Don’t you hate having to go back and do something a second time because it went wrong the first time around? What if you could have avoided that second time altogether?
Although this idea pertains to many everyday activities, in the world of lab testing, this applies quite simply to packaging and shipping samples, specifically rock samples that require the utmost care. After a drilling program has been wrapped up, you don’t want to be the reason for lost time getting samples to the lab.
There are a dozen ways that a sample can be broken or weakened during shipping. Lack of knowledge and/or care can result in dropping, breaking or tampering with the samples which can also reduce the number of tests that can be performed or eliminate the possibility of testing a sample altogether. But, there is a way to save time, energy and money on preserving and transporting rock core samples to testing labs. These are guidelines and best practices developed by ASTM D5079 that we also recommend and use at GeoTesting Express.
Rock samples are delicate and require consideration when packaging up for shipments. Any rock sample can break, fracture or change physical condition if not properly packaged. If you assume that because a rock is ‘hard’ it won’t fracture, you are mistaken. Regardless of who is handling the sample, it is important to secure the ‘goods’ safely in the first place. If a sample is damaged during shipment, a replacement could possibly be shipped, but if not available, it would be very expensive to re-sample in the field. To avoid the hassle altogether here are 3 best practices to consider when packaging and shipping out a rock sample:
The Temperature
- For all samples, the initial moisture content of a core should be preserved.
- It is recommended that the use of a double walled and insulated container, such as a cooler be used to maintain the appropriate temperature of a sample.
- Negative effects: freezing of pore water in the core may reduce the strength of the rock compromising the test results. Additionally, temperatures alternating between hot and cold may cause moisture migration from the core and weaken the rock due to differential thermal expansion and contraction between the grains.
The Packaging
- Wrap samples in plastic wrap, air-tight bags or in aluminum foil and wax coating.
- Standard bubble wrap can minimize vibration during transportation.
The Shipment
- Once specimens are individually preserved, they can be placed inside the cooler of a ridge walled container for shipping. In some cases, shipping the entire core box is necessary.
- It is key to fill voids within the container to minimize vibration and shock (samples should fit snug in whatever container you choose to use).
And just like that, you are ready to ship a sample safely to the lab! There is never a guarantee that something won’t go wrong in the shipping process. Sometimes you get the unfortunate lack of care with a reckless driver that hits every pothole imaginable creating vibration of the samples. The best way to avoid the shipping process having an effect on the precious cargo is utilizing the practices mentioned above. GeoTesting Express routinely provides sample transportation from project sites or client’s offices to our laboratory. Taking great care and utilizing special equipment will save your company time and money and get the best and most accurate results!
Post by: Jon Campbell, GeoTesting Express Lab Manager. Jon Campbell is a Lab Manager for GeoTesting Express. Jon has a B.S. in Geology and started working as a lab technician in GTX’s rock mechanics department back in 2011. As a lab manager, he frequently works with clients on different aspects of their project and address their shipping needs. Jon has helped to implement GTX’s Rock Drillability suite of testing and improve turnaround time within the department. He enjoys working on large and small projects, but his favorite is managing large scale tunneling projects.
