Specifications

4
www.milleruidpower.com
Miller Fluid Power
Des Plaines, IL
Milton, Ontario Canada
Miller. . .
HV2 Series – your best choice in
heavy duty hydraulic cylinders
Miller’s stepped oating cushions
combine the best features of
known cushion technology.
Deceleration devices or built-in “cushions” are optional and can be supplied
at head end, cap end, or both ends without change in envelope or mounting
dimensions. Miller cylinder cushions are a stepped design and combine the
best features of known cushion technology.
Standard straight or tapered cushions have been used in industrial cylinders
over a very broad range of applications, Miller research has found that both
designs have their limitations.
As a result, Miller has taken a new approach in cushioning of industrial
hydraulic cylinders and for specic load and velocity conditions have been
able to obtain deceleration curves that come very close to the ideal. The
success lies in a stepped plunger concept where the steps are calculated to
approximate theoretical orice areas curves.
In the cushion performance chart, pressure traces show the results of typical
orice ow conditions. Tests of a three-step plunger show three pressure
pulses coinciding with the steps. The deceleration curve shape comes very
close to being theoretical, with the exception of the last
1
/2 inch of travel.
This is a constant shape
in order to have some
exibility in application.
The stepped cushion
design shows reduced
pressure peaks for most
load and speed conditions,
with comparable reduction
of objectionable stopping
forces being transmitted
to the load and the support
structure.
All Miller HV2 cushions are
adjustable.
The HV2 Series cylinder
design incorporates the
longest cushion plungers
that can be provided in the
standard envelope without
decreasing the rod bearing
and piston bearing lengths.
Primary Seal – New “Tri-Lip” Rod Seal is
a proven leak proof design – completely
self-compensating and self-relieving
to withstand variations and conform to
mechanical deection that may occur.
Secondary Seal –
Rod Wiper – wipes clean any
oil lm adhering to the rod on
the extend stroke and cleans
the rod on the return stroke.
Piston Rod Stud – Furnished on 2.00"
diameter rods and smaller when standard
style #2 rod end threads are required. Studs
have rolled threads and are made from high
strength steel. Anaerobic adhesive is used to
permanently lock the stud to the piston rod.
Rod Bushing Assembly – Standard bronze
bushing is externally removable without
cylinder disassembly. Long inboard bearing
surface is ahead of the seals assuring
lubrication by cylinder operating uid.
Optional Nodular Iron bushing material is
available at no additional cost.
Steel Head – Bored and
grooved to provide concentricity
for mating parts.
End Seal – Pressure-actuated
cylinder tube-to-head and
cap “O” rings.
Align-A-Groove –
(Patent #3043639) –
A 0.56" wide surface
machined at each end of
the cylinder body. Makes
precise mounting quick
and easy.
CUSHION PRESSURE
TYPICAL STRAIGHT CUSHION
IDEAL CUSHION
TYPICAL STEPPED
CUSHION
CUSHION POSITION
Alloy Steel Tie Rod Nuts
CUSHION PERFORMANCE
Bushing Assembly with “Tri-Lip” Rod Seal
Bushing Assembly externally removable without cylinder
disassembly. An O-ring is used as a seal between the bushing
and head. The “Tri-Lip” rod seal has multiple sealing edges
to produce “dry rod” performance. It is molded from a special
polyurethane material that is extremely resistant to abrasion and
extrusion, resulting in exceptional service life. Wiperseal cleans rod
of dirt, preventing it from entering the bushing and also acts as a
secondary rod seal.
Optional High Temperature
Bushing
Dual lled PTFE rod seals
and lled PTFE wiper seal are
energized with uorocarbon o-rings
to maintain consistent contact with
the piston rod. Excellent sealing
performance produce dry rod on
extend stroke with rod scraping
to clean rod on retract. Combine
with Spring Loaded PTFE Piston
Seals for cylinder heat resistance
to 400° F. See class 8 seal
specication on Operating Fluids
and Temperature Range page.