DESIGN AND APPLICATION OF LARGE-SIZE TWO-STAGE CEMENTER

The Model YFZ-a large-size two-Stage cementer is developed to overcome the troublesome problems-high closing pressure,unsuccessful sealing after closing the circulation ports,and invalid sealing after drilling out the accessories-which might be frequently encountered during the operation of conventional two-stage cementers.The Model YFZ-A two-stage cementer features on its unique structure:the closing sleeve is deployed outside of the cementer main body in order to avoid invalid sealing after drilling out the accessories;the closing sleeve is driven by hydraulic force to close the circulation ports more reliably whereas the closing sleeve of a conventional two-stage cementer is driven by a closing plug,which might result in higher possibilities of unsuccessful sealing.Tests for sealing and other functions have been performed and the testing results show that all performance parameters can meet designed requirements.This product has been utilized successfully in field applications.