Weight-on-Bit
The weight on diamond bits should be somewhat less than for roller cone
bits. A good average weight is between 350 to 750 pounds per square inch
of bit area.
Hole conditions may make it necessary to slack off more weight, but
caution should be used in this respect since excessive weight-on-bit will
shorten its life. Formations which drill by a chipping action produce an
impact load against the diamonds. Drilling weight should be increased in
increments of 2,000 pounds until increases in weight does not show a
comparable increase in the penetration rate. When this occurs, the weight
should be decreased to the lowest weight at which the best penetration rate
was obtained.
The weight on diamond bits should be somewhat less than for roller cone
bits. A good average weight is between 350 to 750 pounds per square inch
of bit area.
Hole conditions may make it necessary to slack off more weight, but
caution should be used in this respect since excessive weight-on-bit will
shorten its life. Formations which drill by a chipping action produce an
impact load against the diamonds. Drilling weight should be increased in
increments of 2,000 pounds until increases in weight does not show a
comparable increase in the penetration rate. When this occurs, the weight
should be decreased to the lowest weight at which the best penetration rate
was obtained.
