BALL DROPPING ASSEMBLY

摘要

A ball dropping assembly 350 for dropping one or more objects, such as spherical balls, 5,5',5" into a wellbore 7. The assembly comprises a seat 330 for retaining a ball before it is released. The assembly may also comprise a ball feeding channel 380 for feeding additional balls onto the seat. A ball retaining lever 40 is provided to selectively receive and retain balls onto the seat 330, and then to release the balls individually into the wellbore 6. In one embodiment, the assembly is attached to a side bore 4 in fluid communication with a main bore in a cementing head 105. The ball-retaining lever 40 rotates into the bore 6 when releasing a ball 5'. When a plug 8 is released into the bore from a cementing head 105, the plug 8 will trip the lever 40, causing the ball-retaining lever to rotate back towards the ball-retained position. Thus, the ball dropping assembly also serves as a plug release indicator.