Study On The Brazing Technique Of PDC Bit

PDC bit has a lot of advantages, such as strong wearability, long-life, high drilling efficiency, low cost, wider range of application and easier to be made. The level of brazing intensity will directly influence its using capability,especially its life. Therefore the brazing technique is an important factor for it. By means of a serious of scientific testing scheme design, a series of systemic experiments and tests were applied on its main factors of PDC bit brazing technique, such as indoor shearing, contrast & wearing and tearing experiments. The test results indicate that cooling beginning temperature after brazing is most influential to its joint strength, then the cooling hours and finally the way of dehydrating before brazing. Brazing temperature and lasting hours have certain influences to wearing and tearing ratio. We know by the experiments that the best parameter groups of brazing technique under the experiment condition before and after brazing: Cooling temperature should be 600℃ at the beginning and keep it for 5 hours, as well as dehydrating in bulk acetone. No filing face of PDC is more effectual than filing one before brazing. Brazing on sand-prayed steel surface is more effectual than non-sand-sprayed one. Non-rusty sand-sprayed surface is more effectual than the rusty one. Non-oxidizing surface is better than the oxidizing one. Cooling effect in the stove after brazing is much better than the natural cooling way. Brazing strength of the brazing material named BAg612 is higher than L312.