Selection Criteria for Rexroth Solenoid Valves (Germany)

Brand

REXROTH/German Rexroth

Flow Direction

Other

3C Valve Category

Industry

Application Areas

Chemical, Petroleum, Energy, Electrical, General

Rexroth Piston Pumps, Rexroth Relief Valves, Rexroth Proportional Valves, Rexroth Vane Pumps

Rexroth solenoid valve selection should first follow four principles in order: safety, reliability, applicability, and economy. Secondly, it should be based on six aspects of the on-site working conditions (i.e., pipeline parameters, fluid parameters, pressure parameters, electrical parameters, actuation method, and special requirements).

Rexroth Solenoid Valve Selection Basis:

1. Selecting the solenoid valve based on pipeline parameters: nominal diameter (DN) and connection type

1) Determine the nominal diameter (DN) according to the on-site pipeline inner diameter or flow requirements;

2) Connection type: Generally, >DN50 requires a flange connection; ≤DN50 can be freely selected according to user needs.

2. Selecting Solenoid Valves Based on Fluid Parameters: Material and Temperature Group

1) Corrosive fluids: Corrosion-resistant solenoid valves and all-stainless steel valves are recommended; Ultra-clean edible fluids: Food-grade stainless steel solenoid valves are recommended.

2) High-temperature fluids: Solenoid valves made with high-temperature resistant electrical and sealing materials should be selected, and piston-type valves are preferred.

3) Fluid state: Fluids can be gaseous, liquid, or mixed, especially when the diameter is greater than DN25, these must be clearly distinguished.

4) Fluid viscosity: Generally, any viscosity can be selected below 50 cSt. If it exceeds this value, a high-viscosity solenoid valve should be selected.

3. Selecting Solenoid Valves Based on Pressure Parameters: Principle and Structural Type

1) Nominal pressure: This parameter has the same meaning as other general-purpose valves and is determined by the nominal pressure of the pipeline.

2) Working pressure: If the working pressure is low, a direct-acting or step-direct-acting principle valve must be selected; when the minimum working pressure difference is above 0.04 MPa, direct-acting, step-direct-acting, and pilot-operated valves can all be selected. 4. Electrical Selection: AC220V or DC24V voltage specifications are preferred for ease of use.

5. Selection Based on Continuous Operating Time: Normally Closed, Normally Open, or Continuously Powered

1) When the solenoid valve needs to be open for a long time, and the duration is longer than the closing time, a normally open type should be selected.

2) If the opening time is short or the opening and closing times are infrequent, a normally closed type should be selected.

3) However, for some safety protection applications, such as furnace and kiln flame monitoring, a normally open type cannot be selected; a continuously powered type should be chosen.

6. Selection of Auxiliary Functions Based on Environmental Requirements: Explosion-proof, Check Valve, Manual Operation, Water-resistant Fog, Water Spray, Submersible.

Rexroth solenoid valves contain a sealed chamber with through-holes at different locations, each connecting to a different oil pipe. Inside the chamber is a piston, flanked by two electromagnets. When the coil of one electromagnet is energized, the valve body is attracted to that side, opening or closing different drain holes by controlling the valve body's movement. The inlet hole is always open, allowing hydraulic oil to enter different drain pipes. The oil pressure then pushes the piston in the cylinder, which in turn moves the piston rod, which in turn drives the mechanical device. Thus, controlling the flow of current to the electromagnets controls the mechanical movement.

Rexroth solenoid valves are electromagnetically controlled industrial devices, fundamental components of automation systems used to control fluids. They are actuators, not limited to hydraulic or pneumatic systems. They are used in industrial control systems to adjust the direction, flow rate, speed, and other parameters of the medium. Solenoid valves can be used with different circuits to achieve the desired control, ensuring both precision and flexibility. There are many types of solenoid valves, each playing a different role in the control system. The most common are check valves, safety valves, directional control valves, and speed control valves.

Rexroth is committed to providing safe, precise, efficient, and cost-effective drive and control technologies for all types of machinery and systems. The company integrates global application experience to develop innovative products, tailoring system solutions and services to customers in every segment of the mobile machinery, mechanical applications and engineering, factory automation, and renewable energy markets. Bosch Rexroth also provides customers with a wide range of hydraulic, electronic drive and control, pneumatic, gear, linear drive, and assembly technologies. The company operates in over 80 countries worldwide, employing more than 37,500 professionals. In 2012, its global sales reached nearly €6.5 billion.

Business Segments

Mobile Machinery:

Construction machinery, material handling equipment, agricultural and forestry machinery, commercial/highway vehicles

Mechanical Applications and Engineering, Factory Automation:

Motion mechanisms, automotive industry, mining, oil and gas drilling (surface), stage technology, chemical industry, printing and paper processing, energy technology, material handling, glass machinery manufacturing, rubber processing, semiconductor and electronics industry, woodworking industry, horizontal directional drilling rigs, engines, plastics machinery and grinding mills, metallurgy, mining equipment, assembly and loading/unloading, dredgers, offshore engineering, processing and packaging, testing technology, recycling and waste management, marine engineering, motion simulation technology, solar energy, machine tools (cutting), hydraulic engineering, tunnel boring machines, metal forming machine tools and presses, conveying technology, fluid dynamics research, shipyard equipment, cement industry, sugar industry, pulp and paper machinery.

Renewable Energy:

Wind Energy

Product Group

Drive Technology, Electronic Drive & Control Technology, Casting Technology, Gear Technology, Industrial Hydraulics, Linear Drive Technology, Travel Hydraulics, Assembly Technology, Pneumatics, Tightening & Welding Technology

Rexroth's Strong Sales Channels

As the Rexroth brand gains increasing recognition in China, many domestic trading companies are beginning to import Rexroth products through overseas channels.

Key Projects

2010 Shanghai World Expo "Magic Ball"

—Bosch Rexroth Drive & Linear Drive Technology

During the 2010 Shanghai World Expo, Bosch Rexroth designed the drive and linear drive solutions and provided technical support for the interactive "Magic Ball" in the German Pavilion. The "Magic Ball" could cycle up to one million times, attracting tens of thousands of visitors. Bosch Rexroth's ingenious solution ensured operational safety and stability, meeting the continuous movement requirements of the "Magic Ball."

National Centre for the Performing Arts, China

—Bosch Rexroth Stage Control System

Bosch Rexroth provided the stage control system for the National Centre for the Performing Arts, China. The main stage of the theater features 15 lifting platforms capable of rapidly and precisely completing a 6.8-meter lifting stroke at a speed of 0.5 meters per second, while strictly controlling the noise level to below 65 decibels.

Wuhan Yangtze River Tunnel

—Bosch Rexroth Hydraulic Cylinders

During the construction of the Wuhan Yangtze River Tunnel, a tunnel boring machine with a diameter of 11.38 meters relied on 72 specially designed Bosch Rexroth hydraulic cylinders equipped with a special sealing system to maintain normal operation under challenging construction conditions.

Shanghai World Financial Center

—Bosch Rexroth Axial Piston Pumps

In 2007, as the Shanghai World Financial Center was nearing completion, the vertical pumping height of a single concrete pump broke the world record at the time. The Bosch Rexroth axial piston pumps installed on this concrete delivery system ensured the pressure required for system operation, guaranteeing the successful completion of the project.

Key Product Highlights

Low Cost, Low Emissions

—Bosch Rexroth Hydraulic Fan Drive System

Global climate change has once again focused attention on the sensitive topics of energy conservation and emission reduction, with increasingly stringent emission standards in various countries. Rexroth's hydraulic fan drive system, with its excellent noise reduction, heat dissipation, and energy-saving performance, enables urban buses to achieve lower emission levels while reducing energy consumption. Compared to traditional hydraulic fan systems, Rexroth's hydraulic fan drive system can save up to 5% on fuel consumption and reduce noise by more than 3 decibels.

The company primarily deals with European and American brands, sourcing from any European country. Key German brands include: BURKERT, DEMAG, HAWE, REXROTH, HYDAC, PILZ relays, FESTO, IFM sensors, E+H, HEIDENHAIN, P+F sensors, SICK, TURCK, and HIRSCHMANN industrial switches. German brands: Hengstler, Murr, Schmersal, Samson, EPRO (Emerson subsidiaries)

American brands: MOOG, ASCO, MAC, NUMATICS, PARKER, VICKERS, ROSS

British brands: Norgren

Italian brands: OMAL, ATOS, CAMOZZI, UNIVER, Camozzi

Our business scope includes:

Hydraulic components such as:

Solenoid directional valves, directional valves, check valves, stack valves, relief valves, counterbalancing valves, proportional valves, manual directional valves, flow valves, pressure reducing valves,

Throttle valves, pressure control valves, back pressure valves, filling valves, flow dividers, shuttle valves, pressure relays, cartridge valves, pneumatic valves, piston pumps,

Gear pumps, vane pumps, cycloidal hydraulic motors, oil coolers, hydraulic cylinders, etc. Pneumatic components include:

Air source processor assemblies, filters, pressure regulating valves, oilers, solenoid valves, pneumatic valves, angle seat valves, manual valves, pull valves, foot valves;

Mechanical valves, check valves, vacuum generators, cylinders, magnetic switches, dampers, pressure gauges, quick couplings, floating couplings;

Pressure gauge switches, water coolers, electric positioners, PU tubing, vacuum suction cups, oil filters, vibrators;

Electrical components include:

Relays, sensors, converters, proximity switches, encoders, programmable controllers;

The company maintains a large inventory, with standard parts readily available. To better serve customers across various industries, the company also distributes other spare parts, with professional sourcing channels and reasonable prices.

The company's products are widely used in industrial machinery, machine tools, plastics machinery, shoe machinery, brick machinery, metallurgy, mining, chemical industry, papermaking, coal mining, shipbuilding, power generation, construction machinery, environmental protection machinery, and many other fields.