Walvoil SD25/2/AC(XG-210)/18L/18L/RC is a 2-spool sectional remote control hydraulic valve within the SD25 high-flow series.This 2 spool hydraulic control valve features a 210-bar main relief setting and two 18L-spool(A-type with detent)working sections.It provides 240 L/min nominal flow at up to 315 bar maximum pressure for drilling jumbos,earth moving equipment,and heavy material handling machinery.

　　What Is a 2 Spool Hydraulic Control Valve?

　　A 2 spool hydraulic control valve is a directional control device that uses two independent sliding spools to regulate hydraulic fluid flow and pressure to separate actuator circuits.Each spool controls one hydraulic function,such as a cylinder or motor,allowing an operator to manage two distinct work functions from a single valve assembly.

　　The SD25 series is a sectional valve platform manufactured by Walvoil(part of Interpump Group‘s Valves Division).Valves within this series are assembled from modular components—inlet element,working sections,and outlet element—secured together with tie rods.This configuration allows from 1 to 12 working sections in a single valve stack.The model SD25/2/AC(XG-210)/18L/18L/RC is a 2-section configuration intended for open-center hydraulic systems.It is designed for remote cable actuation(denoted by“RC”suffix),meaning the valve body can be mounted remotely from the operator station and controlled via flexible push-pull cables connected to a joystick or lever console.

　　Key Specifications

　　Nominal Flow Rate:240 L/min(63.4 US gpm)

　　Maximum Operating Pressure:315 bar(4600 psi)

　　Main Relief Valve Setting:210 bar(3045 psi)

　　Number of Working Sections:2

　　Number of Spools:2

　　Spool Type(Both Sections):18L—A-type,double-acting,with detent positioning

　　Control Method:Remote cable control(RC suffix)

　　Nominal Operating Pressure(T Port):25 bar

　　Internal Leakage:Approx.4 cm³/min at 100 bar(per ISO 4406 test conditions)

　　Spool Diameter:25 mm(0.98 in)

　　Section Pitch(Center-to-Center):62 mm(2.44 in)

　　Oil Temperature Range:-15°C to+80°C

　　Contamination Level Requirement:-/19/16 in accordance with ISO 4406

　　Tie Rod Tightening Torque:50 Nm

　　Housing Material:Special cast iron

　　Spool Material:Steel

　　Seal Material:NBR(Nitrile Butadiene Rubber)

　　Valve Configuration:Sectional,open center

　　Circuit Option:Parallel or series(configurable per application)

　　Port Connections:Inlet P and working ports A/B typically G 1 inch;Tank port T typically G 1-1/4 inch

　　Control Type Classification:Remote control with flexible cable actuation

　　Technical Highlights

　　Main relief valve integrated at inlet protects the entire valve assembly.The AC(XG-210)designation indicates an inlet element with a factory-preset main pressure relief valve set at 210 bar,which limits maximum system pressure delivered to both working sections.This protects downstream actuators and hoses from over-pressurization without requiring external relief components.

　　Individual load check valve on each working section prevents load drop during spool shifting.Every working section in the SD25 series includes a built-in check valve on the pressure channel.This design prevents momentary load lowering when the spool transitions between positions—a critical safety feature for drilling boom positioning and lifting applications.

　　Sectional modular architecture enables field-configurable valve assemblies.The SD25 platform uses tie-rod construction to bolt the inlet element,working sections,and outlet element together as a single rigid block.This allows technicians to add or replace working sections in the field without replacing the entire valve assembly.

　　18L spool type provides detent-positioned A-type double-acting control.The 18L spool designation refers to an A-type control piston that delivers double-acting function with a mechanical detent to hold the spool in position without continuous operator force.This is essential for drilling applications where a function such as feed pressure or boom swing must remain engaged while the operator attends to other controls.

　　Remote cable actuation eliminates hydraulic pilot lines and reduces system complexity.The“RC”suffix indicates compatibility with flexible push-pull cable controls rather than direct manual levers or hydraulic pilot circuits.Cable actuation allows the main valve stack to be mounted in a protected location on the machine chassis,with only lightweight control cables routed to the operator cab—reducing heat exposure and simplifying hose routing.

　　Applications

　　Drill jumbo boom and feed control:Directs hydraulic flow to the boom positioning cylinders and drifter feed circuits on underground and surface drilling rigs.The 18L detent spools allow operators to lock feed pressure during extended drilling cycles without continuous manual input.

　　Earth moving machine attachment control:Manages two independent hydraulic functions on excavators,all-terrain cranes,and motor graders.The 240 L/min nominal flow supports high-speed cylinder actuation for bucket tilt,boom swing,or blade angle adjustment.

　　Large agricultural loader implement circuits:Controls dual-acting cylinders on front-end loaders and telehandlers.The load check valve on each section prevents implement sag when shifting between lift and tilt functions.

　　Material handling equipment actuation:Operates fork positioners,side-shift cylinders,and mast tilt functions on large container forklifts and stackers.The sectional design allows the valve to be configured with additional sections as handling requirements evolve.

　　Waste compactor hydraulic systems:Provides directional control for compaction plate cylinders and container lift mechanisms.The cast iron housing and NBR seals withstand the high-duty-cycle operation and contaminated environments typical of waste handling equipment.

　　Drain machine and municipal vehicle hydraulics:Manages vacuum pump engagement and boom positioning on sewer cleaning and drain maintenance vehicles.Remote cable control enables the operator to position the valve remotely while maintaining precise proportional control feel.

　　Selection Guidance

　　Suitable applications:

　　Hydraulic systems requiring 2 independent directional control circuits with a combined flow capacity up to 240 L/min and maximum operating pressure of 315 bar

　　Applications where remote operator station placement is required and flexible cable actuation is preferred over hydraulic pilot lines

　　Open-center hydraulic circuit configurations(parallel gallery standard;series circuit available as optional configuration)

　　Machines operating within-15°C to+80°C ambient oil temperature range with fluid cleanliness maintained to ISO 4406-/19/16 or better

　　Not recommended for:

　　Load-sensing(LS)closed-center hydraulic systems.The standard SD25/2/AC(XG-210)configuration is designed for open-center circuits.For load-sensing applications,select the SD25 LS variant with appropriate inlet element configuration.

　　Direct manual lever operation.This model includes the“RC”suffix for remote cable actuation.For direct hand-lever control at the valve mounting location,select a manual lever variant without the RC designation,such as SD25/2/AC(XG-210)/18L/18L.

　　Applications requiring more than 2 working sections.This is a 2-section valve assembly.For additional functions,select a 3-section or 4-section variant such as SD25/3/AC(XG-210)or SD25/4/AC(XG-210).

　　FAQ

　　1.What is the maximum flow rate and pressure rating of the Walvoil SD25 series?

　　The nominal flow rate is 240 L/min and the maximum operating pressure is 315 bar(4600 psi).The main relief valve on this specific model,designated by XG-210,is preset to 210 bar.

　　2.What does the model code SD25/2/AC(XG-210)/18L/18L/RC mean?

　　The code decodes as:SD25(series),/2(2 working sections),/AC(XG-210)(inlet element with 210-bar main relief),/18L(first section spool type),/18L(second section spool type),/RC(remote cable control).The 18L spool is an A-type double-acting configuration with detent positioning.

　　3.What are the dimensions,weight,and port sizes of this valve?

　　The complete 2-section assembly weighs approximately 18 kg(calculated from 8.98 kg inlet plus two 4-5 kg working sections).Port connections are G 1 inch for inlet P and working ports A/B,with the tank port T at G 1-1/4 inch.Section pitch is 62 mm center-to-center.

　　4.What is the delivery time or lead time for Walvoil SD25 sectional valves?

　　Manufacturer standard lead time is 4 to 8 weeks for configured sectional valves.Stocked components may ship within 1 to 2 weeks.Contact Beijing Zhongping Technology for current availability and expedited options.

　　5.Is the Walvoil SD25/2/AC(XG-210)/18L/18L/RC in stock?

　　We maintain inventory of common SD25 inlet elements,working sections,and outlet elements for rapid assembly at Beijing Zhongping Technology.Complete configured valve assemblies are built to order with typical lead times of 2 to 4 weeks.

　　6.What type of hydraulic oil and filtration level are required?

　　Mineral-based hydraulic oil with viscosity range of 10 to 380 cSt is suitable.Oil temperature operating range is-15°C to+80°C.Fluid cleanliness must be maintained at ISO 4406 contamination level-/19/16 or better to prevent spool sticking and internal leakage degradation.

　　7.How much does the Walvoil SD25/2/AC(XG-210)cost and what is the price range?

　　The Walvoil SD25/2/AC(XG-210)/18L/18L/RC typically ranges from$2,800 to$4,500 USD depending on configuration,volume,and shipping terms.Prices fluctuate due to exchange rates,tariffs,and factory adjustments.For an accurate quotation,contact Beijing Zhongping Technology directly.

　　8.What is the warranty period and return policy for Walvoil valves?

　　We provide a 1-year warranty against manufacturing defects from date of shipment.Configured sectional valves are built to specification and cannot be returned unless defective.Beijing Zhongping Technology processes warranty claims within 5 business days of receipt.

　　9.Can additional working sections be added to the SD25/2/AC(XG-210)later?

　　Yes.The sectional design allows addition of working sections in the field.This requires longer tie rods and a new outlet element position.Beijing Zhongping Technology provides upgrade kits including tie rods,seals,and installation guidance.

　　10.What are the customs,duty,and import tariff considerations when importing Walvoil valves?

　　HS Code classification is 8481.20(valves for oleohydraulic transmissions).International shipments from Beijing Zhongping Technology are dispatched under Incoterms CPT(Carriage Paid To),with duties,customs fees,and applicable VAT payable by the buyer at delivery.We provide all commercial documentation required for customs clearance.