Check valves, pilot operated SL 6

Description

• Size 6
• Component series 6X
• Maximum operating pressure 315 bar
• Maximum flow 60 l/min

Features

• For subplate mounting
• Porting pattern according to ISO 4401-03-02-0-05 and ISO 5781-03-04-0-00
• For the leakage-free blocking of one actuator port
• With external pilot oil return
• Various cracking pressures, optional
• With or without pre-opening, optional
• Check valve installation sets available individually
• Corrosion-resistant design, optional

Product description

The isolator valve type SV is a releasable check valve for subplate mounting. It is used for the leakage-free blocking of one actuator port, also in case of longer standstill times.

The valve basically consists of a housing (1), a seat poppet (2), a compression spring (3), a control spool (4) as well as of a pre-opening as ball seat valve (7), which is optional.

The seat valve can be flown through from direction A to B without external pilot pressure.

Condition: pA > pB + cracking pressure (compression spring). In the opposite direction, the seat valve closes hydraulically tight.

A sufficiently high pilot pressure at port X moves the control spool (4) in the direction of the seat valve and pushes the seat poppet (2) out of its seat. This allows for a free flow in both directions (active keeping open).

In order to ensure that the seat valve actively opens, the pressure ratios on both sides of the control spool (4) are just as important as the area ratios at the seat poppet (2) or (7).

This results in the following available options for the types

• SV (large spool face A2 (6) connected to pA ) or

as well as for the versions with pre-opening "A" and without pre-opening "B".

Version "A" (with pre-opening)

This valve is provided with an additional pre-opening. By pressurization at port X, the control spool (4) is moved to the right. As a result, the ball (7) is pushed off the seat first and the seat poppet (2) afterwards.

Notes!

Version "A":

• The two-stage set-up with an increased control open ratio means even low pilot pressure can be unloaded securely.

• Avoidance of switching shocks due to dampened decompression of the pressure volume on the actuator side.

Version "B":

• In case of valves without pre-opening, the included pressure volume may be unloaded suddenly. Resulting switching shocks may lead to premature wear on installed components, as well as noise formation.

The modification of type SV to type SL is possible by exchange of plugs (9) and (10). One of the both plugs must always be installed!

Type SL 6 PB.‑6X/…

Type code

1) Only version "B"

2) The selection of the seal material depends on the operating parameters (fluid, temperature, etc.)

Technical data

general

hydraulic

(For applications outside these values, please consult us!)

Diagrams/characteristic curves

Δp-qV characteristic curves

Calculation of the pilot pressure pSt dependent on pA and pB

(measured with HLP46, ϑOil = 40 ±5 °C)

Version "A" (with pre-opening)

Balance of forces:

Assumption: pA = 0

Version "B" (without pre-opening)

Balance of forces:

Assumption: pA = 0

Symbols/Circuit diagrams

Pilot oil return, external

Dimensions

Dimensions in mm

Valve mounting screws (separate order)

4 hexagon socket head cap screws ISO 4762 - M5 x 50 - 10.9

(with friction coefficient μtotal = 0.14);

tightening torque MA = [si]8.9 Nm[/si][/imp]6.6 lb-ft[/imp] ± 10%

(please adjust in case of modified surfaces; use manual torque wrench!)

Downloads

	Hydraulic valves and hydroelectric pressure switches for industrial applications Manual | RE07600-B | 2021-06-21 | English | PDF | 306k Product Groups: Industrial Hydraulics On/off, proportional, high-response and servo valves, pressure switches
	Check valve, pilot operated Data Sheet | RE21460 | 2011-09-01 | English | PDF | 701k Product Groups: Check valves Type SV and SL