drilling sub

DrillingSub is applied in transfer and connection among drill parts in the artesian well operation. ZJSB'Sdrilling Subs are made from 4145 H modified quenched and tempered material to API specifications, and carry the API monogram. ZJSB'sdrilling Sub can be divided into the Same-diameter type, Reducing type, drill bit sub,kelly sub.left-handed type and right-handed type according to its shapes and applications. All connections are cold rolled saver sub and kemplated and furnished with pressed steel thread protectors. How to Order 1. Type of sub required 2. Length - Overall 3. Largest diameter required 4. ID required 5. Size and Type of the upper and lower connections--indicatePIN or BOX. 6. On reduced section subs -- indicate both ODs required 7. On lift subs - indicate bottleneck w/18 tapered shoulders or wafer top 8. On kelly saver subs - indicate whether or not rubber sleeve is required.