are not limited to, but include: forming, drawing, pad forming,
stamping, embossing, coining, compression molding, punching,
blanking, trimming, RIM presses (reactive injection molding),
steel rule die cutting, powder compacting, cut offs, clamping,
trimming, tank head forming, mold/die spotting, die tryout,
heated platen and off center loading
hydraulic press continues to be the press of choice for today's
modern manufacturers. The advantage of the hydraulic press versus
mechanical presses is being realized and utilized by more and
more manufacturers. Today's modern hydraulic presses provide;
Performance, Reliability, and Unlimited Capability in almost
any application. Stamping, Punching, Blanking, Drawing, Bending...
All standard press designs and circuits can be configured to
match even the most non-standard press requirements.
Brought to you by: sealing system hydraulic press company.
Full Tonnage Throughout The Stroke - The hydraulic press has the
ability to deliver full pressing force anywhere in the range of
stroke, unlike mechanical presses which can only develop full
force at close to bottom of stroke. This significantly adds to
the inherent flexibility of hydraulic presses.
Dedicated or Multi-Functional - The hydraulic presses can be designed
to any level of sophistication. Whether the need be a simple dedicated
cell press or a fully integrated multi-purpose system, hydraulics
are cost effective and easily modified for the task at hand. Their
flexibility is further enhanced by additional stroke capability
for simplifying die changes and reducing set-up time. Multiple
dies with varying shut heights can be run efficiently in a single
Lower Up Front Costs / Fast ROI - In regard to presses, hydraulic
presses are the most simple in basic design and often utilize
standardized, proven hydraulic components that are readily available.
The basic components to mechanical presses, such as crankshafts,
clutch and brake systems, etc., are expensive and often custom
built components, which serve to add machine cost. Hydraulic presses
are often much less expensive up-front and in long-term operation.
No Design Limitations - The principles of hydraulic force allow
for creative engineering. Presses can be designed for traditional
down acting, up-acting, side-acting and multi-action operation.
Power systems can be placed above, below or remote from the press
and force actuators. Large bed presses can be designed for low
tonnage applications and small bed presses can be designed for
high tonnage requirements.
Over-Pressure Protection - The incorporation of hydraulic relief
valves into hydraulic circuits provide built-in overload protection.
A press' force cannot exceed the pressure that it is allowed to
build, thereby limiting the maximum pressure attainable controls
Unlimited Control Options - The hydraulic press can be controlled
in a variety of ways ranging from basic relays to more sophisticated
PLC or PC control systems. Operator interfaces can be added to
press systems to facilitate ease of job set by storing individual
job parameters for each die. Presses can be controlled for precise
pressure and position; including pressure holding, speed control
and dynamic adjustments to real-time operating variances. Ram
force and speed can be controlled in any direction with various
levels of precision.
Condensed Footprint - Hydraulics allow for generation of high
pressure over small surface area. This ability reduces the overall
structure required for support of the force actuators. When compared
to mechanical presses, hydraulic presses consume almost 50% less
space for the same tonnage capability. This size advantage results
in lower manufacturing costs and a faster return on investment
by requiring less long-term overhead expense.
Press Industry Terms
amount of possible ram travel. Stroke is the total distance that
the ram can travel, from full extension to full retraction.
distance between the bed bolster and the ram bolster when the
ram is fully extended. This is also commonly known as the Closed
Height. As standard, this dimension is usually within "0.25"
due to assembly processes. For precision shut height requirements,
consult the factory.
distance between the bed bolster and the ram bolster when the
ram is fully retracted. This is also commonly known as the Open
removable plate that serves as the working surface for the bed
and ram. The plate is typically bolted to the bed and ram substructures.
The bolsters can be machined with a variety of work holding features
such as; T-Slots, Drilled and Tapped Holes, Lift Rails for Quick
Die Change, etc...
ram travel of the press may be controlled in a variety of ways.
Most hydraulic presses are standard with Adjustable Retract Limit
Switches to limit the retract distance of the ram (also know as
the Up Limit Position). This can shorten cycle times by only utilizing
the required stroke for part loading and unloading. Other adjustable
limits may include: Slow Down Limit for deceleration from Fast
Speed to Slow Speed; Bottom Stop Position and/or Bottom Stop Pressure,
press may be designed to 'return on pressure'. This method utilizes
a pressure-sensing device, which is adjustable and is set to determine
the desired maximum pressure to be achieved by the ram. Once this
pressure is achieved, the ram typically completes the cycle by
returning to the home position or Up Limit position.
press may be designed to 'return on position'. This method utilizes
either a position sensing device or a limit or proximity switch
that can be set to signal that the desired ram extension has been
Height is the distance from the bottom of the hydraulic press
structure to the working height or top of the bed bolster.
presses are capable of maintaining force on the work for extended
periods of time. This is typically accomplished by using pressure
lock valves or variable volume pumps that are remotely controlled
for precise and long periods of pressure holding.
bed cushion is a commonly required for draw tooling and is a system
that applies resistance when pushed upon. This resistance can
be dynamic or statically controlled throughout the stroke. Bed
cushions have a "pusher pin plate" that is located just
beneath the bed bolster. The bed bolster is provided with multiple
through holes where "pusher pins" are inserted. These
pins are used by the tooling to generate resistive force as the
hydraulic press ram pushes down. The cushion can also be configured
for multiple control zones for on-the-fly dynamic control.
press applications may require that the hydraulics be located
remotely from the press itself. Other applications may preclude
the power system from being able to be installed at the top around
the crown structure of the press. In these cases, the power system
and even the controls may be designed into a separate unit capable
of being placed adjacent to the press or away from the press.
are plates that have heating capabilities. They can be heated
using electric rods, steam, oil, water or other medium. These
systems usually require thermal breaks between the heated plates
and the hydraulic press structure. Heating controls can be separate
or fully integrated into the press control system.
Ram Speeds Do You Need?
presses are normally offered with multiple ram speeds, such as;
Fast Approach, Pressing and Fast Retract. Typically, these speeds
are expressed in Inches Per Minute. The Fast Approach Speed is
designed to lower the ram quickly during the portion of the stroke
that does not require any force. The pressing speed is commonly
referred to as the working portion of the stroke where force is
required and is usually slower. After the working or pressing
portion of the stroke is completed, the ram retracts at a Fast
Retract Speed, which affords little force. This Retract Force
is commonly referred to as the "Stripping Force".
customers with mechanical press experience refer to press speed
in cycles per minute. Hydraulic presses can be designed to provide
a certain amount cycles per minute once the cycle profile has
been determined. The cycle profile consists of an accurate description
of the physical aspects of the cycle. These aspects are:
Distance of ram travel under no load (Fast Approach)
Distance of actual working stroke (Pressing)
Distance of Fast Retract (usually the combination of the previous
Any Dwell Time at the bottom of the stroke or while under pressure
these parameters have been established, the appropriate ram speeds
can be developed in conjunction with the right power system to
provide the necessary cycles per minute.
ram speeds are also available through the use of flow controls
and variable volume pump systems. These and many other cycle profile
characteristics can be provided - ask your Sealing system Press
Engineer for more details.