Spiral drill collar is one kind of
our product series. It?s processed with three right-hand spiral
grooves on the outer cylindrical surface of the circle drill
collar, in order to reduce the contacting areas with well wall and
revolution resistance. It can effectively keep the jamming of the
drill tool from pressing badly. The weight of spiral drill collar
is less 4% than the slick drill collar with the same specification.
The shape on the two ends is similar to cylindrical drill collar.
There are two types according to its spiral grooves:
type?and
type?.
?
