Flow control valves

Hydraulic flow dividers with a 50:50 division ratio in monoblock design are special flow dividers. Their function is to split a single hydraulic flow into two exactly equal partial flows.

This enables the simultaneous and symmetrical control of two consumers with exactly the same flow rates.

The monoblock design ensures that the valve body is manufactured from a single piece, resulting in a very compact, stable and low-leakage to leakage-free construction.

A 50:50 flow divider operates with internally mechanically coupled pistons or spools. These elements are designed so that the incoming flow is hydraulically split into two equal partial flows.

Depending on the design, the partial flows can not only be split, but also recombined (combination of dividing and combining function).

The monoblock design and the mechanical coupling ensure a very precise division of the flow over a wide pressure and load range.

50:50 flow dividers are essential in hydraulic systems where two consumers must be operated simultaneously with exactly the same flow rates.

Typical applications include:

• Synchronous cylinder movements, e.g. in parallel lifting systems
• Control of double-acting hydraulic cylinders with identical speeds
• Mechanical engineering and production systems requiring precise and balanced movements
• Mobile machinery where multiple functions must run synchronously

A 3-way flow control valve is a hydraulic component for flow control. Its main task is to control the flow rate of the hydraulic oil precisely and to keep it constant, even when load and pressure conditions change.

This is crucial for controlling the speed of hydraulic actuators (e.g. cylinders and motors) uniformly and ensuring reproducible motion sequences.

3-way flow control valves have three ports (as opposed to two ports on 2-way valves):

• Inlet (P)
• Controlled outlet to the actuator (A)
• Return line or bypass for excess flow (T)

In 3-way designs, the control orifice and measuring orifice are arranged in parallel. This design enables very efficient flow control, as the surplus flow can be diverted.

By contrast, a 2-way control valve has only inlet and outlet and often "dissipates" excess energy by throttling, which can lead to higher losses.

The exact technical data depend on the type, nominal size and manufacturer. Typical reference values are:

50:50 flow dividers (monoblock design):

• Flow rates: approx. 25 to 60 l/min
• Maximum operating pressure: usually up to 250 bar
• Common port sizes: e.g. G 1/2" (inlet) and G 3/8" (outlets)

3-way flow control valves (line-mounted design):

• Maximum operating pressure: up to 350 bar (depending on version)
• Maximum flow rates: from approx. 60 l/min (e.g. with G 3/8" ports) up to 200 l/min (e.g. with G 1" ports)

Flow dividers in monoblock design are predominantly manufactured from robust materials to withstand high pressures and mechanical loads.

• Steel or aluminium: proven base materials for the housing
• Surface treatments such as zinc plating or nitriding provide additional corrosion and wear protection

3-way flow control valves are typically made from:

• Case-hardened steel for highly loaded components
• Stainless steel for corrosive media or harsh environments
• Aluminium for weight-optimized applications

Maintenance requirements for flow dividers and flow control valves are generally moderate in correctly designed and clean hydraulic systems.

50:50 flow dividers:

• The tightly sealed monoblock design minimizes the ingress of contamination.
• Regular checks of functionality and tightness are still necessary.
• The quality and cleanliness of the hydraulic oil are crucial for service life.

3-way flow control valves:

• Regular inspection for leakage and correct control characteristics.
• In case of contamination or malfunctions, oil filtration and, if necessary, cleaning or replacement are recommended.

With proper installation, clean oil and suitable operating conditions, both components typically achieve a long service life of several years in industrial applications.