Sheffer MH SERIES - Manual (Page 6)

BORE FA FK
1 1 / 8 .3120 3 / 16
1 1 / 2 .3120 3 / 16
2 .3120 3 / 16
2 1 / 2 .3120 3 / 16
3 1 / 4 .5620 5 / 16
4 .5620 5 / 16
5 .5620 5 / 16
6 .6870 1 / 8
Thrust Key Bore Sizes
Tandem Cylinders and
Multi-stage Cylinders
The tandem cylinder
(Figure A)
has two pistons connected to a
common rod, resulting in twice
the force output of a single
cylinder. Multi-stage cylinders
(Figure B) offer multiple, positive
strokes by pressurizing one
cylinder, the other, or both.
Contact the factory for other
variations.
Rod Gland Drain Back
When not even a drop of external
leakage can be tolerated, the rod
gland drain back provides a signal
that the rod seal set has worn to the
point of replacement – without the
danger of contamination from
leakage.
External Rod Seal
When a cylinder is to be operated
under water, provision is made to
prevent the water from being drawn
into the cylinder at the time of
valve shift or pressure differential.
Stainless Steel Piston Rods
Many applications, especially those
subjected to water spray, require
the use of stainless steel piston
rods. We stock AISI Type 304 hard
chrome plated, stainless steel and
will furnish that type unless
otherwise specified. Type 304 is
considered a good, corrosion
resistant type of stainless steel, but
the minimum expected yield is
approximately 35,000 psi and that
factor must be considered with
respect to operating pressure,
column loading, etc.
FIGURE B
FIGURE A
Adjustable Stroke
Shown is an integral stroke
adjustment (externally adjusted)
that is accomplished by the use
of a bump rod threaded into the
cylinder cap. Seals are incorporated
to prevent external leakage and a
lock nut is included.
Thrust Key
All side mounted cylinders (SF, FB,
EL and SL mounts) can be supplied
with thrust keys. Thrust keys are
available in bore sizes 1
1 / 8 " thru 6".
Extending the rod gland retainer,
as shown, provides a key which fits
into a milled slot in the mounting
surface of the machine member.
Combined with the mount this key
assures that cylinder will not shift
in severe service.
Spherical Bearings
Pivot mounting brackets and rod
eyes can be provided with spherical
bearings to compensate for misalign-
ment on both ends of cylinders.
Consider also the use of the Sheffer
Uni-Lign described in separate
Accessories Brochure.
Non-Rotating Piston Rod
Two methods of providing non-
rotating piston rods are employed.
The internal rod type
(Figure A)
is generally used since it requires
less space and is neater. The type
shown in
Figure B must be used
on small bore cylinders where
internal space is limited.
FIGURE A
FIGURE B
The Sheffer Corporation manufactures
many cylinders with variations to meet
special customer needs. In addition to
those illustrated below, some of the
more popular variations are:
• Cylinders with Boots
• Combination Mount Cylinders
• Cylinders with Built-In Limit
Switch Actuators
• Locking Cylinders
• Precision Stroke Cylinders
• Precision Mount Cylinders
• Many More
FK
FA ± .0005
Special Variations
1 MH-5