Specifications

55
www.milleruidpower.com
Heavy-Duty Hydraulic Cylinders
HV2 Series
Catalog HY08-M1140-3/NA
Miller Fluid Power
Des Plaines, IL
Milton, Ontario Canada
Operating Fluids and Temperature Range
Class No.
1 Standard
Nitrile Polyurethane
2 Optional
Water base uid seal
3 Special (EPR) (At extra cost)
Note: Class 3 seals are not compatible with hydraulic oil.
4 Special (Nitrile) (At extra cost)
5 Optional (At extra cost)
(Fluorocarbon Seals)
Note: Class 5 seals are not suitable for use with Skydrol uid, but can be used with hydraulic oil if desired
6 Optional (HWCF) (At extra cost)
8 Optional (At extra cost)
Energized PTFE
Operating Fluids and Temperature Range
Fluidpower cylinders are designed for use with pressurized air, hydraulic oil and re
resistant uids, in some cases special seals are required.
Class 1 Seals
Class 1 seals are the standard seals provided in a cylinder assembly. They are intended
for use with uids such as: air, nitrogen, mineral base hydraulic oil or MIL-H-5606 within
the temperature range of -10°F (-23°C) to +165°F (+74°C). The individual seals may be
nitrile (Buna-N), enhanced polyurethane, polymyte, PTFE or lled PTFE.
Class 2 (Nitrile) Seals
Class 2 seals are intended for use with water base uids within the temperature of
-10°F (-23°C) to +165°F (+74°C) except for High Water Content Fluids (HWCF) in which
case Class 6 seals should be used. Typical water base uids compatible with Class 2
seals are: Water, Water-Glycol, Water-in Emulsion, Houghto-Safe 27, 620 5040, Mobil
Pyrogard D, Shell Irus 905, Ucon Hydrolube J-4. Class 2 seals are nitrile. Lipseal will
have polymyte or PTFE back-up washer when required. O-rings will have nitrile back-up
washers when required.
Class 3 Seals — Ethylene Propylene (E.P.R.) Seals
Class 3 seals are intended for use with some Phosphate Ester Fluids between the
temperatures of -10°F (-23°C) to +130°F (+54°C). Typical uids compatible with Class
3 seals are Skydrol 500 and 700. Class 3 seals are Ethylene Propylene. Lipseals will
have a PTFE back-up washer when required. O-rings will have EPR back-up washers
when required. Note: Class 3 seals are not compatible with mineral base hydraulic oil or
greases. Even limited exposure to these uids will cause severe swelling. PTFE back-up
washer may not be suitable when used in a radiation environment.
Class 4 Seals — Nitrile Seals
Class 4 seals are intended for low temperature service with the same type of uids
as used with Class 1 seals within the temperature range of -50°F (-46°C) to +150°F
(+66°C). Class 4 seals are nitrile seals. Lipseals will have leather, polymyte or PTFE
back-up washers when required. O-rings will have nitrile back-up washers when
required. Note: Certain uids may react adversely with Class 4 seals compared to
Class 1 seals.
Class 5 Seals — Fluorocarbon Seals
Class 5 seals are intended for elevated temperature service or for some Phosphate
Ester Fluids such as Houghto-Safe 1010, 1055, 1120; Fyrquel 150, 220, 300, 350; Mobil
Pyrogard 42, 43, 53, and 55. Note: In addition, Class 5 seals can be used with uids
listed below under Class 1 or Class 2 service. However, they are not compatible with
Phosphate Ester Fluids such as Skydrols. Class 5 seals can operate with a temperature
range of -10°F (-23°C) to +250°F (+121°C). Fluorocarbon seals may be operated to
+400°F (+204°C) with limited service life. For temperatures above +250°F (-121°C) the
cylinder must be manufactured with non-studded piston rod thread and a pinned piston
to rod connection. Class 5 seals are uorocarbon seals. Lipseals will have PTFE back-
up washers. O-rings will have uorocarbon back-up when required.
Class 6 Seals
Class 6 seals are intended for High Water Content Fluids (HWCF) such as Houghton
Hydrolubric 120B and Sonsol Lubrizol within the temperature range of +40°F (+4°C) to
+120°F (+49°C). Class 6 seals are special nitrile compound dynamic seals. Lipseals will
have PTFE and or polymyte back-up washers when required. O-rings will have nitrile
back-up washers when required. Because of the viscosity of these uids, cylinders
specied with Class 6 seals, will also be modied to have lipseal piston seals and
straight cushions.
Class 8 Seals – Energized PTFE Seals
Class 8 seals consist of PTFE piston lipseals, rod seal and wiperseal.Piston seals have
an internal stainless steel spring to energize both the static and dynamic sealing lips.
They are intended for high temperature applications, to 400° F (204° C), where longer
seal life and improved high temperature sealing performance is required. Body and
gland o-ring seals will be uorocarbon. Fluid resistance is comparable to Class 5.
Hi-Load Seals
Hi-Load seals consist of one or two lled PTFE dynamic piston seals with an elastomer
expander underneath. Hi-Load piston arrangement normally consists of a wear ring on
each end of the piston with the seals in the middle. These types of seals are virtually
leak
free seals under static conditions and can tolerate high pressure. The wear rings on
the piston can also tolerate high side loads. The dynamic portion of the seal is bronze
lled PTFE and compatible with all six classes of service. However, carbon lled PTFE
will provide better seal life when used with Class 6 uids. A nitrile expander will be
provided unless Class 3 or 5 seals are specied. In those cases the expander will be of
EPR or Fluorocarbon respectively. Note: It may be necessary to cycle the piston seals
40 or 50 times before achieving leakage free performance.
Lipseal Pistons
Lipseals with a back-up washers are standard in HV2 Series cylinders and are often
used for hydraulic applications when virtually zero static leakage is required. Lipseals
will function properly in these applications when used in conjunction with moderate
hydraulic pressures. A high load piston option is recommended when operating at high
pressures and especially with large bore hydraulic cylinders.
Warning!
The piston rod stud and the piston rod to piston threaded connections are secured
with an anaerobic adhesive which is temperature sensitive. Cylinders specied
with uorocarbon seals are assembled with anaerobic adhesive having a maximum
temperature rating of +250°F (+121°C). Cylinders specied with all other seal
compounds are assembled with anaerobic adhesive have a maximum operating
temperature rating +165°F (+74°C). These temperature limitations are necessary
to prevent the possible loosening of the threaded connections. Cylinders originally
manufactured with Class 1 seals (Nitrile) that will be exposed to ambient temperatures
above +165°F (+74°C) must be modied for higher temperature service. Contact
the factory immediately and arrange for the piston to rod and the stud to piston rod
connections to be properly reassembled to withstand the higher temperature service.
Low Friction Hydraulic Seals
Low Friction hydraulic seals are available as an option for both piston and piston rod
seals for HV2 Series cylinders. They are sometimes used when a cylinder is controlled
by servo or proportional valve. The seal assembly itself is a two piece assembly consist-
ing of a lled PTFE dynamic seal with an elastomer expander. A piston seal assembly
consists of one seal assembly in the middle of the piston with a lled PTFE wear ring on
each side of the piston. The piston rod seal assembly consists of two seal assemblies
and an elastomer wiper seal. The lled PTFE seals are compatible with Class 1, 2, 3,
4 & 5 uids and provide virtually leak free sealing. The expanders and rod wiper will be
nitrile unless Class 3 or 5 seals are specied. In those cases the expanders and wiper
will be EPR and uorocarbon respectively. When specifying low friction seals specify if
piston, piston rod seals or both are required. Note: It may be necessary to cycle these
seals 40 or 50 times before achieving leakage free performance.
Cast Iron Piston Rings
Cast iron rings are optional piston seals for HV2 Series cylinders. They oer the widest
operating conditions by tolerating high operating pressures, wide tempera-ture range
and are compatible with most uids. The only drawback of cast iron rings is that they
allow a small amount of leakage. The leakage for a 4" bore cylinder, operating at 2000
psi, with mineral base hydraulic uid will be less than 10in.
3
/min. Leakage will increase
as pressure, bore size and viscosity of the operating hydraulic uid increases. For these
reasons cast iron rings are not recommended when using water or Class 6 uids.
Water Service
HV2 Series hydraulic cylinders can be modied for water operation and supplied
with chrome-plated cylinder bore; electroless nickel-plated head, cap and piston;
chrome-plated precipitation hardened stainless steel piston rod, chrome-plated cushion
plungers. When high water base uids are the operating medium, hydraulic cylinders
are usually supplied with high water base rod wiper and seals. Water and high water
base uid operated cylinders are best used on short stroke applications or where high
pressure is applied only to clamp the load.
Warranty
Atlas will warrant cylinders modied for water or high water content uid service to
be free of defects in materials or workmanship, but cannot accept responsibility to
premature failure due to excessive wear due to lack of lubricity or where failure is
caused by corrosion, electrolysis or mineral deposits within the cylinder.
Temperature Range
-10°F (-23°C) to
+165°F (+74°C)
-10°F (-23°C) to
+165°F (+74°C)
-10°F (-23°C) to
+130°F (+54°C)
-50°F (-46°C) to
+150°F (+66°C)
See above paragraph on Fluorocarbon seals
for recommended temperature range.
+40°F (+4°C) to
+120°F (+49°C)
-15°F (-26°C) to
400°F (204°C)
Typical Fluids
Air, Nitrogen
Hydraulic Oil, Mil-H-5606 Oil
Water, Water-Glycol, HWCF — See Class 6 below.
Water-in-Oil Emulsion Houghto-Safe, 271, 620, 5040
Mobil Pyrogard D, Shell Irus 905
Ucon Hydrolube J-4
Some Phosphate Ester Fluids
Skydrol 500, 7000
Low Temperature Air or Hydraulic Oil
High Temperature
Houghto-Safe 1010, 1055, 1120
Fryquel 150, 220, 300, 550
Mobil Pyrogard 42,43,53,55
Houghton, Hydrolubric 120B
Sonsol Lubrizol, for other HWCF — consult factory.
See Class 5 Seals