Rexroth Hydraulic Valves Classification

1

M-SR10KE05-1X

Valve body: High-strength carbon steel (CK45); Poppet: Alloy steel (1.4021); Seal: Nitrile rubber (NBR)

1. Contaminants in hydraulic fluid causing poppet wear; 2. Long-term high-pressure impact exceeding rated limits

1. Install a 10μm high-precision filter in the fluid circuit; 2. Regularly monitor system pressure to avoid overpressure operation

2

M-SR10KE02-1X

Valve body: High-strength carbon steel (CK45); Poppet: Alloy steel (1.4021); Seal: Nitrile rubber (NBR)

1. Seal aging due to high fluid temperature; 2. Improper installation leading to poppet misalignment

1. Maintain fluid temperature within 10-60°C; 2. Ensure correct torque during installation (refer to Rexroth standard DIN 259)

3

M-SR15KE05-1X

Valve body: High-strength carbon steel (CK45); Poppet: Alloy steel (1.4021); Seal: Nitrile rubber (NBR)

1. Erosion of poppet seat by high-velocity fluid; 2. Fatigue damage from frequent pressure cycles

1. Ensure fluid flow rate does not exceed the valve's rated value; 2. Conduct periodic inspection of poppet seat wear (recommended every 6 months)

4

M-SR20KE05-1X

Valve body: High-strength carbon steel (CK45); Poppet: Alloy steel (1.4021); Seal: Nitrile rubber (NBR)

1. Contaminant buildup in valve cavity causing jamming; 2. Corrosion due to water ingress in hydraulic fluid

1. Regularly replace hydraulic fluid (every 2000 operating hours); 2. Use desiccant breathers in the hydraulic tank to prevent water contamination

5

M-SR20KE02-1X

Valve body: High-strength carbon steel (CK45); Poppet: Alloy steel (1.4021); Seal: Nitrile rubber (NBR)

1. Seal damage from incompatible hydraulic fluid additives; 2. Mechanical impact during system maintenance

1. Use only Rexroth-approved hydraulic fluids (refer to Rexroth specification 2002); 2. Handle the valve with care during installation and maintenance to avoid impact

6

M-SR30KE05-1X/V

Valve body: High-strength carbon steel (CK45); Poppet: Alloy steel (1.4021); Seal: Fluororubber (FKM); Optional stainless steel components (1.4404) for corrosive environments

1. High-pressure fatigue of valve body; 2. Seal degradation in high-temperature corrosive environments

1. Operate within the rated pressure range (350 bar max); 2. For corrosive applications, select the optional stainless steel configuration

1

M-2SEW6N36/420MG24N9K4

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Spool wear due to fluid contamination; 2. Solenoid coil burnout from voltage fluctuations

1. Install a 5μm filter in the supply line; 2. Use a voltage stabilizer to maintain consistent 24V DC power supply

2

M-2SEW6P3X/420MG24N9K4

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Seal leakage due to high fluid temperature; 2. Spool jamming from improper fluid viscosity

1. Keep fluid temperature below 70°C; 2. Use hydraulic fluid with viscosity between 10-40 mm²/s at operating temperature

3

M-2SEW6P36/420MG125N9K4/V

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Solenoid coil damage from moisture ingress; 2. Valve body corrosion in humid environments

1. Ensure the solenoid connector is tightly sealed; 2. Apply anti-corrosion coating to the valve body in humid working conditions

4

M-3SEW6C3X/420MG24N9K4

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Spool wear from frequent actuation; 2. Spring fatigue in the return mechanism

1. Avoid excessive cycling (limit to 10 cycles per minute); 2. Inspect return springs annually for fatigue and replace if necessary

5

M-3SEW6U3X/420MG24N9K4

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Contaminant buildup in the valve's pilot channel; 2. Overheating of the solenoid due to continuous operation

1. Regularly flush the pilot channel (every 12 months); 2. Use a duty cycle controller for continuous operation to prevent overheating

6

M-3SEW6U3X/420MG24N9K4/V

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Seal damage from chemical attack in aggressive fluid environments; 2. Spool scoring from hard particles in fluid

1. Verify fluid compatibility with FKM seals; 2. Use a multi-stage filtration system (primary 20μm, secondary 5μm)

7

M-3SEW6C3X/420MG24N9K4/V

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Valve body fatigue from pressure spikes; 2. Solenoid connector damage from vibration

1. Install a pressure relief valve to mitigate pressure spikes; 2. Use vibration-damping mounts for the valve assembly

8

M-3SEW6C36/420MG24N9K4/B06

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation; Bracket: Steel (St37)

1. Bracket deformation from improper mounting; 2. Spool misalignment due to bracket stress

1. Follow Rexroth mounting specifications (torque: 8-10 N·m); 2. Ensure the mounting surface is flat and free of debris

9

M-3SEW6C36/420MG25N9Z2/B08/V SO214

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with epoxy resin encapsulation; Bracket: Steel (St37)

1. Solenoid coil failure from overvoltage; 2. Seal leakage due to thermal expansion and contraction

1. Install a surge protector in the electrical circuit; 2. Allow for thermal expansion gaps during installation

10

M-3SEW6C36/420MG24N9K4/B12

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation; Bracket: Steel (St37)

1. Contaminant ingress through damaged seals; 2. Spool wear from abrasive particles in fluid

1. Inspect seals monthly for damage; 2. Replace hydraulic fluid and filters per Rexroth maintenance schedule

11

M-3SEW6U36/630MG24K4/P

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Valve body damage from high-pressure (630 bar) operation; 2. Solenoid overheating in high-load conditions

1. Monitor system pressure closely to avoid exceeding 630 bar; 2. Ensure adequate ventilation around the solenoid coil

12

M-3SEW10U14/420MG24N9K4

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Pilot valve jamming from contaminant buildup; 2. Return spring failure due to corrosion

1. Flush the pilot system every 6 months; 2. Use corrosion-inhibited hydraulic fluid

13

M-4SEW6D3X/420MG24N9K4

Valve body: Ductile iron (GGG40); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Spool wear from high flow rates; 2. Seal damage from fluid turbulence

1. Ensure flow rate does not exceed the valve's rated capacity; 2. Install flow straighteners upstream of the valve

1

M-2SEH10C6X/420-6MG24NS3K4/B08Z5L

Valve body: Ductile iron (GGG50); Spool: Stainless steel (1.4404) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with silicone rubber encapsulation

1. Spool corrosion in offshore/marine environments; 2. Seal damage from saltwater ingress

1. Use marine-grade hydraulic fluid with anti-corrosion additives; 2. Regularly inspect seals for saltwater damage and replace quarterly

2

M-2SEH10U6X/420-6MG24NS3K4/B08Z5L

Valve body: Ductile iron (GGG50); Spool: Stainless steel (1.4404) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with silicone rubber encapsulation

1. Solenoid coil damage from vibration in mobile machinery; 2. Spool jamming from dust and debris in construction environments

1. Use vibration-resistant solenoid mounts; 2. Install a protective cover over the valve to prevent dust ingress

3

M-2SEH10U60/420-6MG24N9S3K4/B08

Valve body: Ductile iron (GGG50); Spool: Stainless steel (1.4404) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with silicone rubber encapsulation

1. High-pressure fatigue of the valve body; 2. Pilot pressure fluctuations causing erratic operation

1. Operate within the rated pressure range (420 bar max); 2. Install a pressure regulator in the pilot circuit

4

M-2SEH10C60/420-6MG24N9S3K4/B08

Valve body: Ductile iron (GGG50); Spool: Stainless steel (1.4404) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with silicone rubber encapsulation

1. Seal degradation from high fluid temperature (exceeding 80°C); 2. Contaminant buildup in the valve's internal channels

1. Install a cooling system to maintain fluid temperature; 2. Conduct annual disassembly and cleaning of internal channels

1

M-3SED6CK1X/350CG24N9K4

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Spool wear from frequent actuation; 2. Solenoid coil burnout from continuous duty

1. Limit actuation frequency to 15 cycles per minute; 2. Use an intermittent duty solenoid or install a cooling fan for continuous operation

2

M-4SED 6D1X/350CG24N9K4

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Valve body damage from pressure shocks; 2. Seal leakage due to improper installation torque

1. Install a shock absorber in the hydraulic circuit; 2. Torque the valve connections to Rexroth's specified value (6-8 N·m)

3

M-3SED6CK13/350CG24N9K4V

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Seal damage from chemical contamination; 2. Spool jamming from foreign particles

1. Test fluid compatibility with FKM seals before use; 2. Use a 3μm high-precision filter in the supply line

4

M-3SED6UK13/350CG24N9K4V

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Solenoid connector failure from moisture; 2. Valve body corrosion in damp environments

1. Use waterproof connectors (IP67 rating); 2. Apply a corrosion-resistant coating to the valve body

5

M-3SED6UK1X/350CG24N9K4

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Spool wear from high-velocity fluid; 2. Spring fatigue in the solenoid

1. Ensure flow rate is within the valve's rated limits; 2. Replace solenoid springs every 2 years or 10,000 operating hours

6

M-3SED6CK1X/350CG2205N9K4

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation (220V AC)

1. Solenoid coil damage from voltage surges; 2. Seal aging from long-term use

1. Install a surge protector in the 220V AC circuit; 2. Replace seals every 18 months regardless of condition

7

M-3SED10CK13/350CG24N9K4

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Contaminant ingress through worn seals; 2. Spool misalignment from mechanical impact

1. Inspect seals monthly for wear; 2. Handle the valve carefully during maintenance to avoid impact

8

M-3SED10CK1X/350CG24N9K4

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Valve body fatigue from cyclic pressure; 2. Solenoid overheating in enclosed spaces

1. Monitor system pressure for cyclic variations; 2. Ensure adequate ventilation around the valve in enclosed installations

9

M-4SED6D1X/350CG24N9K4

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Spool jamming from fluid oxidation products; 2. Seal damage from incompatible additives

1. Use antioxidant hydraulic fluid; 2. Avoid mixing different types of hydraulic fluid additives

10

M-4SED10D1X/350CG24N9K4

Valve body: High-strength carbon steel (CK45); Spool: Alloy steel (1.4021) with hard chrome plating; Seal: Nitrile rubber (NBR); Solenoid coil: Copper wire with epoxy resin encapsulation

1. High-pressure leakage from worn valve seats; 2. Solenoid failure from electrical overload

1. Inspect valve seats annually for wear; 2. Install a circuit breaker in the solenoid power supply

1

M-Z4SEH10E2X/3CG24ETK4

Valve body: Aluminum alloy (6061-T6); Spool: Stainless steel (1.4404) with hard chrome plating; Seal: Fluororubber (FKM); Solenoid coil: Copper wire with epoxy resin encapsulation

1. Valve body corrosion from chemical exposure; 2. Seal damage from high fluid pressure

1. Avoid exposure to corrosive chemicals; 2. Operate within the rated pressure range (350 bar max)

What is the difference between NBR and FKM seals in Rexroth hydraulic valves?

NBR (nitrile rubber) seals are cost-effective and suitable for standard hydraulic fluids (mineral oil-based) with operating temperatures up to 70°C. FKM (fluororubber) seals offer higher temperature resistance (up to 150°C) and chemical compatibility, making them ideal for high-temperature, corrosive, or aggressive fluid environments. Choose FKM seals for applications with high fluid temperature or exposure to harsh chemicals.

How often should Rexroth M-SR series check valves be maintained?

For standard industrial applications, M-SR series check valves should undergo maintenance every 6 months. This includes inspecting the poppet for wear, checking seals for leakage, and flushing the valve cavity. In harsh environments (e.g., construction, mining), maintenance frequency should be increased to every 3 months. Always follow Rexroth maintenance guidelines specified in document number R901282345.

Can Rexroth M-3SEW series valves be used in high-pressure systems above 420 bar?

No. The M-3SEW series valves are rated for a maximum operating pressure of 420 bar (except for specific models like M-3SEW6U36/630MG24K4/P, which is rated for 630 bar). Using valves beyond their rated pressure will cause permanent damage to the valve body, spool, and seals, leading to system failure and potential safety hazards. Always check the product datasheet for the exact pressure rating before installation.