Page 30 - Shale Shakers Drilling Fluid Systems

HISTORICAL PERSPECTIVE 13

Reprint from The Oil Weekly, October 17, 1930.

Vibrating screen in use at General Petroleum Corporation's Moco 218B in
the Maricopa Flat district

Vibrating Screen (Cleans JVlud—

JVlakes JDig Saving

By BRAD MILLS
Staff Representative

T HE use of a special type of vibrating screen to remove needed and most operators thought that nothing could be done
about the high cost of circulation. The installation of a
sand, shales and foreign matter from rotary drilling
mud has proven a very satisfactory innovation at Gen-
reduce mud costs and maintenance of pump parts. It was
eral Petroleum Corporation's Moco 218-B in the Maricopa vibrating mud screen at Moco 218-B followed a decision to
district, where one of the first installations of its kind has obvious that the expense involved with experiments in a new
functioned without interruption for two and one-half months. type of installation was small when compared with the pos-
Application to the petroleum industry of a practice long used sibility of arriving at an improved operating technique.
in other industries for removing undesirable portions of cer-
tain mixtures is considered one of the most important engi- The Apparatus
neering developments of the year. The installation consists chiefly of a rectangular wire screen
While General Petroleum Corporation's installation at Moco cloth mounted on a steel frame and a small electric motor.
218-B in the Maricopa field is only one of several now in use The screen is 30-mesh and four by five feet. The screen frame
fa California, the careful record kept on its operation and the is mounted on four snail house type (coil) springs. On one
success of its action make it perhaps the most interesting of side of the frame and attached to it is a short shaft and
a dozen screens now in use in at least four districts. Installed pulley to handle the belt connected to the motor.
in the nature of an experiment, the layout has been operated The screen is placed in the regular mud circuit so that the
from the beginning with few changes in the original design. entire volume passes over or through it. The electric motor is
The growing tendency toward reclaiming rotary drilling mounted a short distance above the upper end of the screen
mud has been apparent for more than a year and many opera- and on one side of it. The screen is tilted at an easy angle to
tors have kept careful records on the cost of this phase of facilitate the drop of the sand and shales, but the motion of
drilling. Thousands of tons of mud has been discarded in the the frame and screen while in normal action does not make
Maricopa district over a comparatively short period, the cost a very delicate adjustment necessary. A short slide is placed
of replacing that lost having been a good percentage of the immediately below the screen to give the coarse particles
total drilling cost. Shales and sand at certain depths have momentum. A one-inch perforated pipe crosses the slide im-
rendered the mud useless in very short periods. Early in the mediately above it, the play of water from the pipe washing
development campaign in the district new mud was mixed as the sand and cuttings to a distant point by means of a gal-