Description

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Shijiazhuang Laiye Import& Export Trading Co., Ltd. is one of the leading manufacturers and suppliers of sv/sl hydraulic check valve in China, also supports customized service. If you're going to wholesale high quality sv/sl hydraulic check valve made in China, welcome to get pricelist from our factory.

Custom properties

A regular check valve does one thing: lets flow go one way, blocks it the other. Simple. But sometimes you need to open that blocked direction on command. That's what this valve does.

The SV/SL Hydraulic Check Valve is a pilot operated check valve. It seals in one direction - no leakage, no drift. When you apply pilot pressure, it opens the reverse direction. Hold a load securely, then release it when you're ready.

Two versions. SV without drain port. SL with drain port. Both do the same job - the difference is how they handle back pressure.

Available in NG10, NG20, and NG30 sizes. Max flow up to 350 L/min. Max pressure up to 315 bar.

If your application needs load holding - clamping, press holding, cylinder locking - this is the valve.

Transaction

Minimum order quantity: 10 pieces
Payment method: T/T, Paypal, Western Union
Supply Ability: Annual output of 1,000,000
Delivery time: 10-15 days
Conventional packing: Wooden case

PRODUCT PARAMETERS
Specification	20
Max working pressure Mpa	31.5
Max.Flow (L/min)	350
Design Number	40

Product description

SV SL Hydraulic check valve information

SV SL Hydraulic check valve detail

SV SL Hydraulic check valve data

SV SL Hydraulic check valve detail data

1.Ports A and B

2.PortX, G 1/4°or M14X1.5

3.Nameplate

4.Two fixed through holes for the valve, 210.5mm

5.PortY, G 1/4cr M14X 1.5mm

Size L7 is only applicable to opening pressure 2

Size L8 is only applicable to opening pressure 3

Valve Model		B1	B2	B3	φD1	D2
SV/SL	10	66.5	85	40	34	G1/2'orM22X1.5
	15	79.5	100	55	42	G3/4°orM27X2
	20	79.5	100	55	47	G1'orM33X2
	25	97	120	70	56	G11/4"orM42X2
	30	97	120	70	61	G11/2'orM28X2

Valve Model		H1	L1	L2L	L3	L4	L5	L6	L7	L8	L9	T1
SV	10	42	27.5	18.5	10.5	33.5	49	80	116	119	一	14
	15	57	36.5	17.5	13	50.5	67.5	95	135	146	一	16
	20	57	36.5	17.5	13	50.5	67.5	95	135	146	一	18
	25	75	54.5	15.5	20.5	73.5	89.5	115	169	179	一	20
	30	75	54.5	15.5	20.5	73.5	89.5	115	169	179	一	22
SL	10	42	22.5	18.5	10.5	33.5	49	80	116	116	51.5	14
	15	57	30.5	17.5	13	50.5	72.5	100	140	151	72.5	16
	20	57	30.5	17.5	13	50.5	72.5	100	140	151	72.5	18
	25	75	51	15.5	20	84	99.5	125	179	189	99.5	20
	30	75	51	15.5	20	84	99.5	125	179	189	99.5	22

Company Development History

1988

Founded in 1988

2000

Gain ISO9002

2001

Gain Export rights

2019

The total sales reached 250 million, and the exports reached 5 million US dollars

2022

Get more export advantage

How it works

Normal operation. Flow passes freely from A to B. Flow from B to A is blocked by the poppet and spring. The load stays put. No leakage.

Pilot operation. Apply pilot pressure to port X. A piston pushes the poppet off its seat. Reverse flow opens - B to A. The load can move.

Release. Remove pilot pressure. The spring pushes the poppet back onto the seat. The valve closes. The load holds again.

That's the sequence. Hold, release, hold again. Controlled by pilot pressure.

Where it fits in the system

The SV/SL doesn't work alone. It works with a directional control valve.

The directional valve controls the actuator. The SV/SL holds the load when the directional valve is centered. When you want to release the load, the directional valve sends pilot pressure to the SV/SL. The check valve opens. The load moves.

This is how you get secure load holding with controlled release. No leakage when closed. Full flow when opened.

Installation - what matters

Mounting. Subplate mounting. Confirm porting pattern matches your manifold.

Port connections. A and B are the main flow ports. X is the pilot port. For SL type, Y is the drain port.

Drain port (SL type). Connect the drain port directly to tank. This prevents back pressure from affecting pilot operation.

Maintenance. Keep oil clean. The poppet and seat are hardened - they last a long time with clean oil. If leakage develops, the poppet or seat may be worn. Contact us for replacement parts.

Where it belongs

The SV/SL Hydraulic Check Valve is used wherever load holding and safety locking are critical:

Clamping systems - hold workpieces without drift

Hydraulic presses - hold pressure between cycles

Cylinder locking - prevent drift when the valve is centered

Safety circuits - prevent uncontrolled movement on power loss

Mobile equipment - boom holding, outrigger locking

About the company

Shijiazhuang Laiye Import & Export Trading Co., Ltd., part of Hebei Onederful® Hydraulic Technology Co., Ltd., has been making hydraulic components since 1988 - over 35 years.

We're a factory, not a trading company. Around 200 employees. Full in-house production: casting, machining, assembly, testing, phosphating.

Products go to Russia, Europe, the Middle East, South America, and Asia. ISO 9001 certified. Every valve is tested individually, with data linked to its serial number.

FAQs

Q: Are you trading company or manufacturer ?

A: We are the manufacturer.

Q: Are OEM services available?

A: Yes, just provide your drawing and your requirements.

Q: How long does it take to process orders?

A: It usually takes 10-14 business days to process most orders for no stock, if stock available, only take 2- 3 business days.

Q: Can the valve open if the pilot pressure is insufficient?

A: No. The minimum pilot control pressure must be reached to actuate the control piston and open the poppet valve. If the pilot pressure is insufficient, the valve spool cannot open the reverse flow passage.

Q: The system is failing to maintain pressure; is the valve the problem?

A: Uncertainly. Failure to maintain pressure could be caused by wear on the valve spool's sealing surface, internal leakage in the cylinder due to damaged seals, leaks at pipe connections, or internal leakage within the directional control valve.