Walvoil SD5/5-P(KG4-210)is a 5-section monoblock directional control valve for mobile machinery.Configured as a directional control valve with parallel circuit architecture,this monoblock hydraulic valve delivers a nominal flow of 45 L/min at a maximum operating pressure of 315 bar.It is engineered for outrigger stabilizer leg control on truck-mounted cranes,aerial platforms,and concrete pump trucks.

　　What Is a Monoblock Directional Control Valve?

　　A monoblock directional control valve is a hydraulic component that integrates multiple spool sections within a single cast body to direct pressurized fluid to different actuators in sequence or parallel.Unlike sectional valves assembled from individual blocks,the monoblock design eliminates inter-section seals and external tie rods,reducing potential leak paths and overall envelope dimensions.

　　The SD5/5-P is a parallel-circuit monoblock valve within the Walvoil SD5 series.Its 5-section configuration allows independent control of up to 5 hydraulic functions—typically four stabilizer legs plus one auxiliary circuit—through manual lever actuation with spring return to center.The"P"suffix denotes parallel circuit architecture,while"KG4-210"specifies the main pressure relief valve factory setting at 210 bar.

　　Key Specifications

　　Number of Sections:5

　　Circuit Type:Parallel(Open Center)

　　Nominal Flow Rate:45 L/min(per manufacturer datasheet)

　　Maximum Operating Pressure:315 bar(per manufacturer datasheet)

　　Main Relief Valve Setting(KG4-210):210 bar

　　Maximum Return Pressure:25 bar

　　Control Method:Manual Lever with Spring Return

　　Spool Function:A-Type(Open Center)

　　Free Flow Gallery:Type S(per manufacturer catalog)

　　Plunger Diameter:16 mm

　　Plunger Stroke Length:37 mm

　　Port Size(P/A/B/T):G 3/8"BSP(ISO 228/1)

　　Housing Material:Cast Iron Body,Steel Spool

　　Seal Material:NBR(standard)

　　Fluid Temperature Range(NBR Seals):-20°C to 80°C

　　Ambient Temperature Range(Mechanical Controls):-40°C to 60°C

　　Maximum Contamination Level:ISO 4406 Class 19/16

　　Hydraulic Fluid:Mineral base oil(HL,HLP type)

　　Viscosity Range:15 to 75 mm²/s(operating),12 mm²/s minimum,400 mm²/s maximum

　　Internal Leakage A(B)to T:3 cm³/min at 100 bar and 40°C

　　Mounting Orientation:Any angle(per manufacturer guidelines)

　　Approximate Weight:Consult manufacturer datasheet for exact mass

　　Compliance:ISO 9001:2015 certified manufacturing facility(Walvoil Dongguan SGS certificate)

　　Technical Highlights

　　Substantial spool dimensions support heavy-duty cycling.The 16 mm diameter plunger with 37 mm stroke provides robust flow metering authority and resistance to spool binding under thermal expansion or fluid contamination,which is critical for outrigger circuits that remain pressurized under static load.

　　Type S free-flow gallery enables power beyond functionality.The open-center gallery design allows series connection of additional valves downstream without interrupting flow,supporting complex hydraulic systems where a pump supplies multiple valve stacks.

　　Four-grade relief valve system protects downstream actuators.The KG4 designation specifies a cartridge-type main relief valve available in four factory-calibrated pressure grades up to 315 bar,with this unit preset to 210 bar—matching typical stabilizer leg working pressures.

　　Open-center parallel circuit minimizes energy waste in standby.When all spools are in neutral,pump flow circulates through the gallery back to tank at near-zero pressure,reducing heat generation during idle periods common in mobile machinery operations.

　　Applications

　　Truck-mounted crane outrigger control:Directs hydraulic flow to four stabilizer legs for vehicle leveling.The 210 bar relief setting protects against overload when legs encounter uneven terrain or obstacles during deployment.

　　Aerial work platform stabilization:Controls manual stabilizer circuits on trailer-mounted platforms where individual leg positioning is required to compensate for site slope.

　　Concrete pump truck stabilizer actuation:Manages front and rear outrigger cylinders for pump truck stabilization,handling return flows up to 25 bar without cavitation.

　　Small loader and agricultural machinery:Provides implement control for front-end loaders and small tractors requiring up to five simultaneous hydraulic functions,per Walvoil application documentation.

　　Service crane and utility vehicle hydraulics:Serves as the primary directional control valve for service cranes and municipal vehicles where simple,robust manual control is preferred over electrohydraulic alternatives.

　　Selection Guidance

　　Suitable applications:

　　Mobile hydraulic systems requiring 5 manually actuated directional control functions in a single compact valve body,with design preference for BSP G 3/8"ports

　　Outrigger and stabilizer circuits operating at 45 L/min maximum flow with pump pressures up to 315 bar,where 210 bar relief valve setting is within the actuator design limit

　　Systems needing open-center parallel circuit architecture where pump flow circulates freely in neutral position

　　Installations where NBR seals are compatible with the hydraulic fluid,maintaining viscosity between 15 and 75 mm²/s and fluid temperature from-20°C to 80°C

　　Not recommended for:

　　Series circuit applications requiring a closed-center design.Select a Series-type variant with"S"suffix instead of"P"(parallel).The SD5/5-S alternative provides identical flow and pressure ratings with series flow path configuration.

　　Applications exceeding 45 L/min flow demand or requiring more than 5 sections.For higher flow,consider the SDM100 series(70 L/min)or SDS180 series(160 L/min)from Walvoil.If more than 5 sections are needed,the SD6 modular sectional valve series supports up to 12 sections.

　　Electrohydraulic remote control requirements without additional solenoid interface.The standard SD5/5-P ships with manual lever actuators.For remote electric control,specify the electrohydraulic control option or consider the SD6 series,which offers factory-integrated electric actuation.

　　FAQ

　　1.What is the flow rate and maximum operating pressure of the SD5/5-P?

　　Nominal flow rate is 45 L/min.The maximum operating pressure for the parallel circuit configuration is 315 bar.The return line maximum pressure is 25 bar per manufacturer datasheet.

　　2.What are the port sizes and thread type on this valve?

　　All working ports(P,A,B,T)are G 3/8"BSP threads conforming to ISO 228/1 standard.This is consistent across the entire SD5 series.

　　3.Is the Walvoil SD5/5-P in stock and what is the lead time or delivery time?

　　Beijing Zhongping Technology maintains inventory of Walvoil SD5 series valves for immediate fulfillment.Standard manufacturer lead time is 4 to 6 weeks for non-stock configurations.Contact us for real-time stock status and shipment schedule.

　　4.How much does the Walvoil SD5/5-P cost?What is the price range?

　　The SD5/5-P typically ranges from 1,200to1,800 USD per unit depending on configuration,volume,and distribution channel.Prices fluctuate due to exchange rates,tariffs,and factory adjustments.For an accurate quotation with current pricing and delivery terms,contact Beijing Zhongping Technology directly.

　　5.What is the warranty period and return policy for the Walvoil SD5/5-P?

　　We provide a 1-year warranty against manufacturing defects.A 2-year extended warranty option is available upon request.Returns require prior authorization and are subject to inspection.Beijing Zhongping Technology processes RMA requests within 48 business hours of receipt.The manufacturer warranty does not cover seal damage from incompatible hydraulic fluids.

　　6.What hydraulic fluid and viscosity does the SD5/5-P require?

　　The valve is designed for mineral base hydraulic oil(HL or HLP type per ISO 6743/4).Minimum fluid cleanliness level is ISO 4406 Class 19/16.Viscosity must remain within 15 to 75 mm²/s during operation,with 12 mm²/s minimum and 400 mm²/s maximum allowable range.

　　7.What payment terms do you accept for Walvoil valve purchases?

　　We accept bank wire transfer(T/T)and major credit cards.For qualified corporate accounts with established credit history,Beijing Zhongping Technology may offer net 30 payment terms upon approval.

　　8.Can the SD5/5-P be installed in any orientation?

　　Yes.The monoblock valve body accepts any mounting angle.Ensure the reservoir return line is positioned to prevent siphoning and that vent or drain ports,if present,remain unobstructed.Always fasten the valve rigidly to the machine frame to prevent vibration-induced fatigue.

　　9.What maintenance or spare parts are available for the Walvoil SD5/5-P?

　　Beijing Zhongping Technology stocks common spare parts including seal kits,replacement relief valve cartridges,and manual lever assemblies.Seal replacement intervals depend on fluid cleanliness,operating temperature,and duty cycle.NBR seals degrade above 80°C;verify fluid operating temperature before selecting seal material.

　　10.What are the customs duty,tariffs,and import documentation requirements for the Walvoil SD5/5-P?

　　The HTSUS code is 8481.20.0050 and ECCN classification is EAR99.International shipments are dispatched under Incoterms FCA(Free Carrier)or CPT(Carriage Paid To)depending on destination.Duties,customs fees,and applicable VAT are payable by the buyer at the time of delivery.Beijing Zhongping Technology provides commercial invoices,packing lists,and certificate of origin documents required for customs clearance on all export orders.