The sealing principle for Kelly valve is to ensure a close seat between the ball and the ball seat. The lower seat is supported by a spring. The force provided by the spring keep the ball securely in place with lower seat. During normal drilling operation, the hole is kept unblocked by turning the stem to “on” position; In case of kick or blowout, turn the operating stem to “off” position to close off the internal bore of drill string, the kick or blowout accident is avoided due to a high pressure sealing situation between ball and the ball seat.
When ordering please specify
● Upper or Lower type;
● Tool OD;
● Working pressure: 5,000 / 10,000 / 15,000 psi;
● Tool connection.