User Manual

11
© Ashcroft Inc., 250 E. Main St., Stratford, CT 06614-5145, Tel: [phone], Fax: [phone], www.ashcroft.com
All sales subject to standard terms and conditions of sale.
I&M008-10173-3/10 (1188)
A
SHCROFT
®
T
ype 1188 Bellows Gauge
Calibration Procedure
C
ALIBRATION & TROUBLE
CORRECTION DIAGRAM
P
OINTER JUMPING
SLUGGISH MOVEMENT
NON LINEAR
STICKY PARTS
Clean all bearings
and gear teeth
RANGE SPAN ADJUSTMENT
RANGE TOO SHORT
Adjust slide “S” inward
RANGE TOO LONG
Adjust slide “S” outward
LOOSE HAIRSPRING
Remove backlash by
disengaging pinion &
rotate to tighten
COUNTER BALANCE
RUBBING
Bend if necessary to
c
lear socket in travel
N
OTE: After adjusting range span, set both movement stops.
Set the underload stop so that the pointer will stop at
zero. Set the overload stop so that the pointer will pass
the maximum range approximately 5˝.
NOTE: After adjusting span re-zero pointer by removing from
pinion and re-assembling at the proper dial mark.
NOTE: To increase or decrease angle “A,“ bend tip inward or outward as
required. Doing this may run the movement segment off the pin-
ion. This can be corrected by cutting off one end off the link “E”
decreasing its length, or makin a new length from .032 dia. phos.
bronze wire.
Caution: When reproducing link end, follow figure 44 very closely.
this will prevent too much play, or, binding in operation.
REF: Replacing System Bellows
After assembling bellows to the gauge socket securely, subject sys-
tem to 30 psi for five minutes, allowing bellows to travel approxi-
mately 1/8˝ against the overload stop. After this, heat treat system for
15 hours at 250°F, this procedure is necssary to prevent gauge drift.
TIGHT HAIRSPRING
Loosen by disengaging pinion & rotate
NON LINEAR
FIRST 3RD.
NON LINEAR
LAST 3RD.
ADJ. ANGLE OF PULL
BY INCREASING ANGLE “A”
ADJ. ANGLE OF PULL
BY DECREASING ANGLE “A”
STOP LOCKING
SCREWS
OVERLOAD
STOP
SLIDE AND LINK (angle “A”)
Enlarged view of slide and link
UNDERLOAD
STOP
1/8
60°
.020 R
E (LINK)
S (SLIDE)