Memorandum from A. Waltner and N. Underwood to Dr. Clifford Beck
1 p.
April 16, 1951


April 16, 1951

TO: Dr. Clifford Beck
FROM: A. Waltner and N. Underwood
SUBJECT: Control Rod Mechanism

The pull which can be exerted by a Brown recorder balancing motor to
move the pen was measured and found to be approximately 10 lbf. The time
required for a full scale motion of the pen without 10 lbf load was found
to be approximately 20 sec. When the 10 lbf load was applied the time for
full scale travel was approximately 27 sec. Since it is anticipated that
the time desired for the complete withdrawal of the control rod is 15 min,
it is seen that the additional gear reduction which will be needed will
result in a theoretical pull of about 300 lbf. This so far exceeds the
requirements that it is unnecessary to make estimates to take friction
into account.

Therefore, it is concluded that a Modified Brown Recorder mechanism
may be suitable for moving the rods.

CC: Reactor Committee