Zdaz CTH hydraulic presses 1

ZDAS Forming Machines
The forming machines have been built by the joint-stock company ŽĎAS for more than half a century. From basic simple types manufactured at the beginning according to the adopted documentation, this line was extended to several specialized groups after having established the company s own development base. Nowadays, ŽĎAS is able to meet all common as well
as specific requirements of its customers for press design or parameters.
Thanks to experience of the designing team and up-to-date production plants, the design and implementation of specífic unit or special machines are also offered in addition to unified series of single types of forming machines today. it mainly con-
cerns the equipment for mass production of parts for the automotive or consumer industry provided with appropriate mecha-
nization equipment, tooling and all accompanying services.
ŽĎAS ranks among the prominent manufacturers of forming machínes, who are also able to design for their customer the
equipment according to its special requirements, so-called tailor-made equipment. Therefore, a good reference is not only
number of equipment supplied in single types, but also tens of production lines and machines designed and supplied accor-
ding to customers requirements.
These days, considerable attention is paid to medium repairs and general overhauls of not only the equipment buïlt by us earlier
but also the equipment from other manufacturers. Repairs are aimed not only at functional wear of single parts of the presses but also at safety elements necessary to operate the given equipment nowadays. Much of repairs are associated with modernization of the presses, wifh change of the drives and other parts of the presses to meet requirements of present up-to-date technologies.
Essentially, the forming machines built under the ŽĎAS trademark are divided, according to the drive system, into mechanical and hydraulic presses. Thereat, however, the use for both sheet-metal forming and solid forming is respected. Both types of the machines are paid the same attention in separate specialized teams of specialists then. With respect to the fact that the use of the machines with various drives for productíon of particular pressings often intersects, a group of ŽĎAS technological
specialists always tries to find an optimum and various-purpose equipment for the particular pressing or blank.

design and manufacture of forming machines
Classification of Hydraulic Рresses
accordíng to the Technology
Uníversal presses CTH, CTC, CTL
Straighteníng presses CDN, CDT
Railway wheel sets CDR, CDRA
Pipe bends CXT
Automotive and aircraft industries CYA, CYAA, CYAB, CTUA, CTV
Specíal presses Thin-walled hollow bodies CTP, TYH, CKQ
B1ack-lead extrusion presses CXQ
Powder metallurgy CJZ
Food processing CYX
semi-automatic
Too1 change device automatic
Press accessories with run-out tables
Ejectors, clamps etc.
Uncoilers, straighteners, feederś,
Mechanizatíon equipment loaders etc.
Automotive industry
Too1-makíng Progressive forming
Consumer industry
Special tools
Automotive industry
Mechanical engineering
Supply of formíng línes Metallurgical production
Special production
Reconstruction of hydraulic Sectional repairs
General overhauls
presses Modernization
Hydrauiic Press Drive
Prínciples

Principles of the drives of hydraulic presses manufactured by ŽĎAS, caп
be divided in two groups, water-emulsion and oi1 ones. The water-emulsion
principle is mostly used for forging presses and the oi1 principle, both direct or
combined, is used for forming hydraulic presses.
The company deals with the designs of industrial applications being operated
with both hydraulic oi1 and water emulsion.
ŽĎAS, being the prestigious manufacturer of forming machines for various
industrial applications holds the unchanging philosophy of delivering its
machines as complete and ready for use, including hydraulic, electronic and
electric control systems.
The oi1 and hydraulic elements and hydraulic power units are mostly provided
by reputable world manufacturers, such as BOSCH REXROTH, OILGEAR-
TOWLER, WEPUKO etc., while the controI manifolds and a11 machine groups
are designed and manufactured by ŽĎAS company using PC with the support Direct dnve
of SW NX in 3D model.
j For big hydraulic systems, the accumulator drives are used with a water emul-
ık sion HFA fluid used as working liquid. The accumulator dríves being also ca1-
1ed accumulator stations ensure drive even for more presses. The advantage
of the above accumulator station is that it is designed for the average con-
sumption of driven presses. The hydraulic-šhock problem in the pipe at a long
; distance of the accumulator station from the presses has been solved by the
1 incorporation of an absorber in this piping. For accumulator drives, the hyd-
raulic control and power elements of the same concept are used as those
intended for oi1 drives. They on1y differ in the material used and minor design
modifications. The great advantage in the development of this element base
for water emulsion hydraulics is the fact that the company is furnished with
their own forging shop having suitable equipment, thus achieving a high pro-
ductivity. The presses installed in the forging shop are connected to the cent-
ra1 accumulator station and undergo regular machine modernization. Desig-
, ning departments of ŽĎAS company have had a chance to make sure of new
engineering solutions at any time in practice under heavy-duty conditions of
a forging shop. 1n addition to the accumulator station, we can mention as an
example the realized projects with accumulator drives, such as CKQ 630/220
press modernization, railway wheel-set line tor BONATRANS Bohumín etc.
Two principles of hydraulic drives, direct and combined, find their applica-
Combined drive tion in hydraulic presses with oi1 drives. The hydraulic drive of the press is se-
lected according to the characteristics of individual technological operations
for which the press is intended. The direct hydraulic drive is suitable to be
used for sheet metal forming, extrusion, straightening, baling or cutting the
scrap, and for isostatic compacting.
The combined hydraulic drive is used for the technologies requiring a high
nominal force of the press at high forming velocities. The combined drive is
operating in a way that, in the part of the press nominal force range, the accu-
mulator together with hydraulic power unit delivers the liquid hydraulic oi1 to
working hydraulic cylinders. 1n the final forming phase the accumulator is dis-
connected and the liquid is delivered by the hydraulïc power unit on1y. The
accumulator also ensures the supply of liquid to working hydraulic cylinders
when moving back of the press ram. This drive principle is used for CYAA
designated presses as we11, which are intended for the plastic sheet metal for-
ming technology.