Downhole sampling method and device used in standard penetration test

摘要

A sampling device has a closed housing, a split-barrel sampler, an anvil, a drop hammer and a lifting device. The split-barrel sampler is mounted in and extends out from the bottom end of the housing. The anvil is attached to the top of the split barrel sampler. The drop hammer is moveably mounted in the housing and is located above the anvil. The lifting device is mounted in the top end of the closed housing to lift the drop hammer to a specific height above the top of the anvil. With the sampling device, the impact energy generated by the hammer is directly transmitted to the sampler through the anvil. The impact energy lost is minimized, and the accuracy of the Standard Penetration Test result is improved.