DAW 20 B1-5X/100-17-6EG24N9K4/12

Manufacturer: Bosch Rexroth

Material #: R978913545

Model : DAW 20 B1-5X/100-17-6EG24N9K4/12

***Disclaimer: The following summary contains information gathered from various sources such as product descriptions, technical specifications and catalogs. While efforts have been made to provide accurate details, inaccuracies may occur. It is advised to verify all information by contacting Bosch Rexroth directly.***
The Bosch Rexroth DAW 20 B1-5X/100-17-6EG24N9K4/12 (R978913545) is a sophisticated pilot-operated pressure cutoff valve designed to efficiently manage hydraulic system pressures and flow. This particular model is notable for its freely adjustable switching pressure differential, which allows for precise control over the charging and discharging cycles of accumulators in hydraulic circuits. The valve achieves this by alternating between pressurized circulation when the accumulator charging pressure is met and depressurized circulation once the system pressure drops by the set switching pressure differential. This model incorporates a main housing, pilot control valve, main spool insert, and check valve to regulate the flow from P to B and P to T. The operation of this valve ensures that when a set cutoff pressure is reached, it switches the flow internally or externally via port Y to maintain system stability. The DAW 20 B1-5X/100-17-6EG24N9K4/12 features an adjustment spindle that can be manipulated to modify the top switching pressure, with a factory setting at nominal pressure offering an approximate switching pressure differential range. Furthermore, this model includes a nozzle in its control line for potential shock damping purposes, enhancing performance by managing circulation pressures. It's important to note that while this valve does not directly limit pump pressure to the tank, it achieves an indirect limiting function through its various components. For mounting flexibility, options such as subplate mounting and cartridge valves with various adjustment types are available. Additionally, this valve can be solenoid-operated for unloading via a built-on directional spool valve. It is designed for maximum operating pressures up to bar and can handle maximum flow rates of l/min. Users must ensure that all necessary ports for actuator A, pump P, tank T, control lines, and check valves are appropriately selected and installed according to size requirements and flow characteristics for optimal performance.

$2,833.00 USD

More are expected on June 26, 2025

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Status: This product is temporarily out of stock.

Qty: Delivered as early as June 26, 2025 when ordered in

This product is eligible for factory repair.

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For subplate mounting As cartridge valve 4 adjustment types, optionally:
• Rotary knob
• Adjustment spindle with protective cap
• Lockable rotary knob with scale
• Rotary knob with scale 4 pressure ratings Solenoid-operated unloading via built-on directional spool valve

Type DAW…FS… (freely adjustable switching pressure differential)

The pressure valve type DAW is a pilot-operated pressure cut-off valve. For example, it is used in accumulator charging circuits. Here, an accumulator is filled until the accumulator charging pressure is reached. After reaching the accumulator pressure, the valve switches the flow to depressurized circulation until the pressure in the hydraulic system has fallen by the switching pressure differential. Afterwards, the charging process is started again.

The pressure cut-off valve generally consists of main housing (1), pilot control valve (2 and 3), main spool insert (4) and check valve (7).

Switching of the pump flow from P to B to P to T.

The pump delivers via the check valve (7) into the hydraulic system (P to A). The pressure applied in channel A acts via the control line (8) on the control spool in the pilot control valve (3). Simultaneously, the pressure in channel P is applied via nozzle (5) to the spring-loaded side of the main spool (4) and via the control line (9) and at the inlet (11) of the screw-in cartridge valve (3). As soon as the top cut-off pressure set at the screw-in cartridge valve (3) by means of the adjustment spindle (12) is reached in the hydraulic system, the screw-in cartridge valve opens the connection from the spring-loaded side of the main spool (4) to the return line (10) to T internally (type DAW ...) or externally via port Y (type DAW ...Y).

Due to the nozzle (5), a pressure drop occurs at the main spool (4). It is lifted from the seat and opens connection P to T. The check valve (7) closes the connection from P to A. The actuator pressure A holds the screw-in cartridge valve (3) in open position.

Switching of the pump flow from P to T to P to A.

If the actuator pressure A has fallen to the pressure value set at the adjustment spindle (14), the screw-in cartridge valve (3) switches to initial position and closes the connection from the spring-loaded side of the main spool (4) to the return line (10). This way, the pressure on the spring-loaded side of the main spool (4) is increased and the connection from P to T is closed by the compression spring (6). The pump again delivers via the check valve (7) into the hydraulic system from P to A.

Version "FSB07"

The nozzle of this valve is located in the control line (11) for potential switching shock damping. This way, the circulation pressure (P to T) is increased. See characteristic curves.

Notices!

Only indirect pressure limiting function:

A pressure limiting function of the pump pressure (to the tank) is not directly provided but only indirectly via the check valve (7), control line (8) and pilot control valve (2) to channel T.

Setting the switching pressure differential

At the factory, the valves are set at nominal pressure to a switching pressure differential of approx. 10 % to 12 %. A setting of 50 % of the nominal pressure is possible.

On delivery, the adjustment spindle (12) is screwed out and set to the minimum adjustable switching pressure.

By screwing in the adjustment spindle (12), the top switching pressure may be increased.

The switching pressure differential is adjusted via the adjustment spindle (14): Screw out to reduce, screw in to increase.

The pressure adjustments are secured via the clamping screw (13) and lock nut (15).

Different system conditions (particularly high pump and actuator flows) may lead to higher switching pressures than indicated in the characteristic curves. Here, the valve offers the possibility of optional adjustment of the switching pressure differential to the system.

Type DA 10 -2-5X/.FS…

Type DAW… (fixed switching pressure differential 10 % or 17 %)

The function of this valve complies with the function of version "FS". At the pilot control valve, however, only the top switching pressure and not the switching pressure differential can be set.

The pilot spool surface (16) exceeds the effective ball (17) surface optionally by 10 % or 17 %.

This way, the effective force at the pilot spool (16) exceeds the effective force at the ball (17) by 10 % or 17%.

Switching of the pump flow from P to B to P to T.

The pressure in channel P is applied via nozzles (5) and (9) to the spring-loaded side of the main spool (4) and at ball (17) in the pilot control valve (2). As soon as the cut-off pressure set at the adjustment spindle (12) is reached in the hydraulic system, the ball (17) opens against the spring (18). The hydraulic fluid now flows via nozzles (5) and (9) into the spring chamber (19) to the return line (10) to T (type DAW ...) or externally via port Y (type DAW ...Y). The main spool (4) is lifted from the seat and opens connection P to T. The check valve (7) closes the connection from P to A. Via the pilot spool (16), the actuator pressure A holds the ball in the pilot control valve (2) in open position.

Switching of the pump flow from P to T to P to A.

If the actuator pressure A drops by the switching pressure differential range of 10 % or 17 % in comparison with the set cut-off pressure (according to characteristic curves on page 11), the spring (18) closes the ball (17) in the pilot control valve (2). This way, the pressure on the spring-loaded side of the main spool (4) is increased and the connection from P to T is closed by the compression spring (6). The pump again delivers via the check valve (7) into the hydraulic system from P to A.

Type DA 10 -1-5X/…

The function of this valve complies with the function of valve type DAW …. However, switching can be realized as required from P to T or from P to A by means of solenoid-actuated directional spool valve (20) for pressure below the set cut-off pressure.

Type DAW 20 -1-5X/…6E..K4…

Type DAWC…

Pressure cut-off valve type DAWC 30 …FS…

This valve consists of pilot control housing (2), screw-in cartridge valve (3) as pilot control element and a main spool insert (4).

Pressure cut-off valve type DAWC …10/17...

This valve consists of pilot control valve (2) and an optional main spool insert (4).

Notice for circuit design with type DAC...

The ports required for actuator (A), pump (P) and tank (T), the required control lines (8) and (10) as well as the required check valve (7) are not included in the scope of delivery. These have to be selected according to the applicable size and the flow. Connections require sufficient cross-section and blocking has to be prevented by appropriate design and layout. Between actuator (A) and pump (P), a sufficiently dimensioned check valve with flow characteristics in compliance with or exceeding the characteristic curves specified on page 12 has to be applied.

01	02	03	04	05		06		07		08		09	10	11	12		13	14	15	16	17	18
DA					–		–	5X	/		–					–						*

01	Pressure cut-off valve			DA
02	with attached directional spool valve			W
03	Valve complete (subplate mounting)			no code
	Pilot control valve without main spool insert (cartridge valve) (do not enter nominal size)			C 1)
	Pilot control valve with main spool insert (cartridge valve) (enter valve size 30)			C
04	Size 10			10
	Size 25			20
	Size 32			30
05	Symbols	Normally closed	Normally closed	A 2)
		Normally open	Normally open	B 2)
Adjustment types
06	Rotary knob			1
	Adjustment spindle with protective cap			2
	Lockable rotary knob with scale			3 3)
	Rotary knob with scale			7
07	Component series 50 … 59 (50 … 59: unchanged installation and connection dimensions)			5X
Pressure adjustment range
08	25 to 50 bar			50
	50 to 100 bar			100
	100 to 200 bar			200
	200 to 315 bar			315
Switching pressure differential (P → A)
09	on average 10 %			10
	on average 17 %			17
	freely adjustable switching pressure differential (see characteristic curves)			FS 5)
Damping nozzle 6)
10	without nozzle			no code
	Nozzle Ø 0.7 mm (see characteristic curves)			B07 7)
11	Pilot oil return, internal			no code
	Pilot oil return, external			Y
12	with directional spool valve (high-power valve, data sheet 23178)			6E 1)
13	Direct voltage 24 V			G24 1)
	Alternating voltage 230 V, 50/60 Hz			W230 1)
14	With concealed manual override			N9 1)
	With manual override			N 1)
	Without manual override			no code
Electrical connection
15	without mating connector, individual connection with connector according to DIN EN 175301-803			K41; 4)
Seal material
16	NBR seals			no code
	FKM seals (other seals upon request)			V
	Observe compatibility of seals with hydraulic fluid used.
17	Further details in the plain text			*

	1) Only versions "10" and "17".
	2) Ordering code only required for versions with mounted directional spool valve "DAW".
	3) H-key with material no. R900008158 is included in the scope of delivery.
	4) Mating connectors, separate order.
	5)Only with version "2".
	6) With nozzle: Switching shock damping leads to increased circulation pressure (P → T)
	Without nozzle: Undamped leads to reduced circulation pressure (P → T) (see characteristic curves)
	7)Only with version "FS"

Preferred types and standard units are specified in the EPS (standard price list).

general

Size			10	25	32
Weight	Type DAW	kg	5.3	9.2	15
	Type DAW …FS	kg	5.8	9.8	15.6
	Type DAWC …	kg	2.4
	Type DAWC 30 …	kg	2.9
	Type DAWC 30 …FS	kg	3.4
Installation position			any
Ambient temperature range	NBR seals	°C	-30 … +50
Ambient temperature range	FKM seals	°C	-20 … +50

hydraulic

Size			10	25	32
Maximum operating pressure	Port P	bar	315
	Anschluss A 1)	bar	315
	Port T 2) 3)	bar	100
	Port Y 2) 3)	bar	100
Set pressure range	Pressure rating 50	bar	25 … 50
	Pressure rating 100 4)	bar	50 … 100
	Pressure rating 200 4)	bar	100 … 200
	Pressure rating 315 4) 5)	bar	200 … 315
Switching pressure differential	Version "FS"		freely adjustable (10 % to 50 % of nominal set pressure)
	Version "10" 4)	%	10
	Version "17" 4)	%	17
Maximum flow	Version "FS"	l/min	120	250	400
	Version "10"	l/min	40	80	120
	Version "17"	l/min	60	120	240
Hydraulic fluid			Mineral oil (HL, HLP) according to DIN 51524, other hydraulic fluids on request
Hydraulic fluid temperature range	NBR seals	°C	-30 … +80
	FKM seals	°C	-20 … +80
Viscosity range	Maximum	mm²/s	10 … 800
	Recommended	mm²/s	20 … 60
Maximum admissible degree of contamination of the hydraulic fluid 6)			Class 20/18/15 according to ISO 4406 (c)

1)	(after switching P to T)
2)	Attention! The applied pressure adds to the set pressure! The switching pressure differential remains unchanged within the setting range!
3)	The tank pressure must not exceed the pump pressure.
4)	For switching pressure differential adjustment, the following points must be observed:The top and bottom switching points must be within the setting range of the pressure rating (e.g. for a pressure rating of 100 bar: top switching point 100 bar, bottom switching point 50 bar ≙ 50 % switching pressure differential)– The minimum switching pressure differential mainly depends on the system (set pressure, pump and actuator flow, accumulator size and preload, line length and resistance, etc.) Here, the valve offers the possibility of optional adjustment of the switching pressure differential to the system. For these reasons, however, the minimum adjustable switching pressure differential of the valve cannot always be realized at the system. – Generally: Reduce the tubing between pressure cut-off valve and hydraulic accumulator to a minimum and ensure depressurized pilot oil (Y) discharge as possible. – For the switching pressure differential factory setting, refer to the respective information sheet.
5)	Type DA …FS... 150 to 315 bar
6)	The cleanliness classes specified for the components must be adhered to in hydraulic systems. Effective filtration prevents faults and simultaneously increases the life cycle of the components. For the selection of the filters, see www.boschrexroth.com/filter.

For applications outside these parameters, please consult us!

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

Size 10

Circulation pressure dependent on flow qV P and damping (P → T)

Size 25

Circulation pressure dependent on flow qV P and damping (P → T)

Size 32

Circulation pressure dependent on flow qV P and damping (P → T)

Notice!

The flow depends on the set switching pressure differential.

Pressure rating 50 bar

Switching pressure differential (P → A) dependent on the cut-off pressure pO (type DA …)

Pressure rating 100 bar

Switching pressure differential (P → A) dependent on the cut-off pressure pO (type DA …)

Pressure rating 200 bar

Switching pressure differential (P → A) dependent on the cut-off pressure pO (type DA …)

Pressure rating 315 bar

Switching pressure differential (P → A) dependent on the cut-off pressure pO (type DA …)