Air Pressure Amplifiers
Haskel International has nearly 60 years of hydraulic and pneumatic engineering
experience in the design and manufacture of high pressure generating equipment
and controls. Continuous investment in the new machinery and technology
keeps Haskel at the forefront of the field.
We offer the most comprehensive range of models in the industry combining:
- Simple principles of operation
- Rugged construction
- Capability to meet the most demanding industrial applications
Haskel Air Amplifiers provide an alternative to purchasing dedicated
high pressure compressors. They are compact, require no electrical or
mechanical drive connections, are powered by the same air they amplify,
and can be mounted in any position.
What is a Haskel Air Pressure Amplifier?
An Air Pressure Amplifier is an air pump that is driven by part of the
incoming compressed air supply enabling it to cycle and pump the balance
of the supply to a higher output pressure.
Pressure is generated by the use of a differential area piston assembly.
Low pressure air applied to a large area creates high pressure air on
the small area. Cycling is achieved through the use of two pilot valves
that alternately pilot and vent the large area end of a cycling spool.
The small area end of the cycling spool uses a permanent air spring. This
unbalanced cycling spool ensures that the air amplifier cycles on demand.
Unique Haskel seal technology enables the drive section of its pressure
generating products to operate without air line lubrication. No lubrication
of any kind is used in the high pressure sections where non-metallic bearings
and wear compensating seals are employed.
The ratio of the areas between the connected pistons is called the area
ratio and is the dash number used in all model codes. This ratio and the
available air drive source pressure determines the maximum outlet pressure
of the air amplifier.
The completely sealed air amplifier will "stall" at its maximum
capable outlet pressure and consume no energy or generate any heat while
doing so. When pressure drop is seen at the air amplifier outlet, the
unbalanced spool ensures cycling to make up the pressure loss and will
again "stall" after having done so.
Double acting and two stage models are available which provide increased
output and efficiency as well as using input air directly on the high
pressure piston(s) in both stroke directions to increase drive force and
output pressure capability.
A proven range of horsepower sizes is available to meet most high pressure
air requirements; from our 1/3 HP for low flow/static applications to
our 8 HP used for high flow dynamic applications.
Haskel Air Pressure Amplifiers are powered and controlled by the same
compressed air they boost (amplify), with no electrical connections. And
their minimal overall size makes them easy to install.
Key Features
- Infinitely variable outlet pressure and flow capability
- No heat, flame or spark risk
- No air line lubrication required - eliminates oily exhaust
- Long seal life with easy maintenance
- Wide range of models, controls and options
- Wide range of standard and custom systems
Selecting an Air Amplifier
Several factors are involved in the proper sizing of Haskel air amplifiers.
Some involve the specific parameters of the application while some involve
the application itself.
Specific parameters include:
- What is the outlet pressure required (Po)?
- What is the minimum available air drive pressure (Pa)?
- What is the available air drive flow (Qa)?
- What is the supply pressure (Ps)? (In most cases, Pa = Ps)
- What is the required flow (Q) at the outlet pressure?
Application data includes:
- What is the duty cycle?
- What is the high pressure required for?
- Testing - what is the volume of the vessel and time required?
- Part ejection - what is the cycle of volume requirements?
- Actuation
- what is the bore & stroke of the actuator(s)?
- single or double acting?
- is high pressure air required on each stroke (double acting)?
Which stroke?
- is high pressure air required for the entire stroke length(s)?
- what are the cycle requirements?
Dividing the outlet pressure (Po) by the drive pressure (Pa) will provide
us with the minimum area ratio of the amplifier(s). (The dash number in
the model code represents the area ratio.) More than one amplifier may
be required: in certain high flow or heavy duty applications two or more
amplifiers can be used in parallel; in certain higher flow/high pressure
applications, a two-stage amplifier or multiple amplifiers can be used
in series. Haskel offers a range of standard multi-pump units. Multi-pump
units are most effective when the models selected produce the same flow
for their respective pressure amplification.
We should verify the determination of flow required (Q) by evaluating
the application data. Finding that high pressure air is required only
at the end of stroke or only on one stroke of the cycle may reduce the
initial assessment of Q.
Another consideration will be whether an air receiver used downstream
can reduce the size of the amplifier required when the system cycle is
taken into account (use high pressure air from the receiver during the
on cycle and recharge the receiver during the off cycle) or enable momentary
high flow requirements that initially are thought to exceed the capacity
of our units. Haskel offers system options that include air receivers
and controls.
Operating Guidelines
Download Operating & Maintenance Instructions:
While Haskel manufactures air amplifiers for a wide range of pressures,
care must be taken when sizing units for high outlet pressure applications.
All air contains moisture and as you compress air, the moisture level
does not reduce along with the volume of the air. The result is the same
volume of moisture in a reduced volume of air. This saturation can lead
to excessive maintenance for the air amplifier and the system. Dry, inexpensive
gases such as nitrogen can be effectively used in the high pressure sections
for these higher outlet pressure requirements (60OPSIG and higher for
example). For critical gas quality, refer to the use of our gas
booster compressors which feature separation between drive and high
pressure sections.
Other considerations include cycling rate and operation in unloaded conditions
(i.e. before supply pressure has equalized or with small differential
between supply and outlet pressures). Proper sizing of the air amplifier
will avoid regular operation where the outlet pressure is too small of
a percentage of the maximum outlet pressure capability for the drive and
supply pressure conditions. Cycling rate will be a factor of outlet pressure
but can also be controlled by "throttling" the air drive volume.
Various manual and automatic controls are available to prevent "no
load runaway".
Maximum cycle rate is a factor of drive piston size, cycling mechanism,
drive pressure, etc., and varies according to drive series. The maximum
outlet flow and cycling speed are represented on the performance curves
at the point where the outlet pressure and supply/drive curves intersect.
These maximum cycling rates are not recommended for continuous duty (where
the pressure and flow requirements for a system are constant) and the
air amplifier performance should be derated for these applications to
approximately 50% of maximum. Cycling speed at a given outlet flow can
be calculated by dividing the SCFM outlet flow by the SCF
("free air volume") displacement per cycle.
SCF/Cycle = (Db/1728) x ((Ps + 14.7)/14.7) x 0.85
Where:
- Db = Displacement per cycle (cu. in.)
- Dividing by 1728 provides Actual Cubic Foot displacement
- Ps = Supply pressure
- Adding & dividing by 14.7 converts to Absolute Atmospheres
- 0.85 = Efficiency factor (approximate)
When the maximum outlet flow from a performance curve has been determined,
it can be converted to cycling speed (divide SCFM by SCF/Cycle). This
cycling speed can then be derated for a continuous duty application and
converted to rated continuous outlet flow (multiply SCF/cycle x derated
cycle speed) for improved seal life. Multiple units can be used in parallel
if necessary to meet required outlet flows and maintain acceptable cycle
rates for continuous duty applications.
Model Ranges
Click on the links below to view detailed information on each model.
Typical Applications
Air Pressure Amplifiers
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