Page 4 - Parker - L90LS Mobile directional control valve

Catalogue HY17-8504/UK Mobile Directional Control Valve
General Information L90LS

The L90LS is a stackable, multi-section, directly by means of levers or remotely by Examples of optional functions
load-sensing, pressure-compensated pneumatic, electro-pneumatic, hydraulic Depending on the application and oper-
directional valve for mobile machines such or electro-hydraulic remote control. Some ating criteria of the machine, a wide range
as cranes, skylifts, forklift trucks, platform of our remote-controlled spool actuators of common, section- or port-specific
trucks, excavators and harvesters. It is can be fitted with a supplementary direct optional functions can be integrated into
designed for working pressures of up to lever to give a dual-control and/or emer- the L90LS. Examples include:
320 bar and a maximum pump flow of gency facility. The wide range of actuating • a bypass function in the inlet section for
200 l/min. The valve can be given excel- options gives the machine designer great systems fed by fixed pumps.
lent simultaneous-operating character- freedom in terms of control criteria and
istics, which enable several machine component location. • a pump-unloading function that blocks
functions to be operated responsively at the pump inlet when activated, thus
the same time, regardless of the sizes of Customisation and economy enabling an emergency-stop function
individual loads. The L90LS can be tailored optimally to to be incorporated into the system.
To facilitate precise customization control either simple or complex machine- • section-specific pressure compensa-
for different applications, the L90LS is functions and combinations thereof. tion.
of wholly modular construction. Each Its facilities for integrating total, wholly • port-specific relief and anti-cavitation
valve is therefore built to order, so that it customized solutions for a wide range of functions.
incorporates exactly the valve functions applications give low system costs and
and values needed to control the given minimal energy consumption. • port-specific feed reduction.
machine in an optimal way. • port-specific force-feedback functions
Safety and serviceability that enable force-sensing and also
Compact, integral system The design of the L90LS makes it easy provide a hydraulic ramp function.
construction for machine manufacturers to comply with • a load-signal copying function to elimi-
national and international safety regula-
The total modularity of the L90LS gives tions, such as those contained in the EC nate micro-sinking.
unique opportunities to integrate a wide Machinery Directive. Special safety func- • a built-in pilot-pressure function in the
range of normally external functions into tions for machines such as cranes and end section.
the valve. Such functions can be common skylifts can be integrated into the valve in
or specific to individual spool-sections, so a logical and simple way. With all system • a counter pressure function that gives
that widely differing criteria for individual functions contained in a robust, compact, exceptionally good make-up character-
machine functions can be met in just one pre-tested unit with minimal external istics and the possibility of unloading
valve. This enables compact, tailored, pipework, overall safety and reliability lowering movements.
logical, pre-tested, service-friendly system is greatly improved at the same time as • section-specific two-speed functions
solutions to be created for many different servicing and the training of personnel is that enable switching between perform-
types of machine. made much easier. ance and precision work in machines
In situations where flow demands vary such as cranes and skylifts.
so greatly that two separate directional Spool sections and flow rates • automatic stopping functions for
valves would normally be required, the The L90LS can be supplied in combina- selected machine movements in the
L90LS can, with the aid of a special tions of 1-12 spool sections or in combina- event of overload or the reaching of
combo-inlett, be flanged to a larger valve tion with special function manifolds fitted other pre-determined limits.
such as the K170LS or K220LS to give between spool sections. The maximum
a compact, unitized system solution and recommended flow rate per spool section • priority for machine functions such as
brakes and steering.
optimum economy. is 125 l/min, or 90 l/m when equipped with
a pressure compensator. • Flow distribution between different
Wide range of spool actuators consumers at maximum flow take-off
The spools in the L90LS can be actuated from the pump.
4 Parker Hannifin
Mobile Controls Division Europe
Borås, Sweden