PA VB 40/1000 Zero User manual

Ultimo aggiornamento: 15/11/19
1
P.A. –S.p.A. –EQUIPAGGIAMENTI TECNICI DEL LAVAGGIO
VIA MILANO, 13 –CASELLA POSTALE 115 –42048 RUBIERA (REGGIO EMILIA) –ITALY
Tel. [phone] –Fax. [phone] –R.E.A. RE 156319 –R.I. RE11535 –Mecc. RE 013446
C.F. e P. IVA 01035950359 –Cap. Soc. i.v. € 750.000,00 – Codice Identificativo C.E.E. IT 01035950359
ART. 2497 –BIS C.C. DIREZIONE E COORDINAMENTO BENETTI srl R.I. TRIB. DI RE 01480690351
. Web: http://www.pa-etl.it –E-mail: [email protected]
VB 40/1000 Zero -Flowsensitiveunloader valve PATENTED
Pressure regulating valve unloader type with zero setting on delivery line: at
gun closure the water flow is bypassed at low pressure maintaining also the
delivery line in low pressure.
Technical manual: MPA0004EN
DN 10
TECHNICAL SPECIFICATIONS
Construction material: Sst.
PART
NUMBER
MINIMUM
FLOW
MAXIMUM
FLOW
WORK
PRESSURE
ADJUSTABLE
MINIMUM
PRESSURE
MAX
TEMPERATURE (1)
WEIGHT
IN
OUT
BYPASS
l /min
USG
l / min
USG
bar
MPa
bar
MPa
°C
°F
g
oz.
60.2900.00
9
2.4
40
10.5
1000
100
500
50
95
203
4650
164
G 3/8” F
G 3/8” F
60.2900.12
9
2.4
15
4.0
1000
100
500
50
95
203
4650
164
G 3/8” F
G 3/8” M
60.2900.20
9
2.4
25
6.5
1000
100
500
50
95
203
4650
164
G 3/8” F
G 3/8” M
60.2900.30
9
2.4
35
9.2
1000
100
500
50
95
203
4650
164
G 3/8” F
G 3/8” M
1) The valve has been designed for a continuous use at a water temperature of 60°C (140°F).
It can work for short periods at a maximum temperature of 95°C (203°F).
•60.2900.XX VB 40/1000 Zero G 3/8” FF
oNear total zero setting of the pressure in the delivery line at gun closure.
Advantages:▪Increased safety for the operator.
▪Delivery hose easy to control when gun is closed.
▪Less force needed to reopen the gun.
oAt gun reopening, work pressure is reached gradually.
Advantages: ▪Operators work less heavy.
▪Easy starting if thermal engine is used.
oReduced pressure loss and hardly dependent on flow rate.
oGreat reliability.
oEasy maintenance.
oThree versions with different working pressure but one sole range of flow
rate from 9 up to 40 l/min.
▪

Ultimo aggiornamento: 15/11/19
2
MISURE DI INGOMBRO
SELECTION
This product is intended to be incorporated on a finished machine. This product is to be utilized with clean fresh water, even slightly
additivated with normal detergents. For use involving different or corrosive liquids, contact the PA Technical department. Appropriate
filtration should be installed when using unpure liquids. Choose the valve in line with the working data of the machine where to be
installed (permissible pressure, maximum flow and rated temperature of the system). In any case, the pressure of the machine must
not exceed the permissible pressure imprimed on the valve.
Attention. The VB40/1000 Zero valve is sensitive to water flow: at gun opening (water flow through the valve) the system goes into
pressure, at gun closure (flow interruption) the system works at low pressure. For this reason, the VB40/1000 zero valve cannot be
installed on systems that fit always weeping antifreeze systems. Instead it can be installed on systems with antifreeze systems
weeping at low pressure. In this case it is necessary to create in the bypass line a pressure higher than the pressure at which the
antifreeze system becomes weeping.
OPERATIONS
The valve regulates the maximum pressure of the system by variating the flow discharged by the bypass. The adjustment is made by
altering, by means of a piston, the position of a sphere which closes partially the bypass opening.
The valve is sensitive to water flow. At gun opening, the water flows through the valve which maintains the system in pressure. At gun
closure, the interruption of the flow provokes the complete aperture of the bypass which allows to discharge the flow at low pressure.
At gun closure, the special mechanism of zero setting patented by PA, which does not include a check valve, keeps in connection the
delivery line and the bypass line, in that way permitting to lower the pressure all around the system and not only in the source line of
the valve.
INSTALLATION
This accessory, on a system that produces hot water, must be fitted upstream the heat generator. On a system that generates hot
water, it is advisable to fit in accessories that limit the accidental increase of fluid temperature.
Do not install the valve on the pump head: secure the valve to the machine’s frame by means of the fixing holes obtained on the
body. In this way the valve is subject to less vibrations, reducing therefore the wearing of the internal parts. The hose from the pump to
the valve must have a minimum length of about one meter. Always install a safety valve for protect the system.
If the nozzle wears out, the pressure decreases. To reset pressure back at work level, it is necessary to replace the worn nozzle.
When a new nozzle is fitted, re-setting of the system to its original working pressure is required.

Ultimo aggiornamento: 15/11/19
3
DISCHARGE SYSTEM AND WATER ADDUCTION
The valve can be fitted on machines fed directly by the water system with bypass recycle to the pump or on machines fed by a tank
where the bypass flow is also discharged.
In certain conditions, depending on installation and in particular:
othrough feeding from tank,
owith long delivery lines or strong difference in level,
owith low flow rate and small flow factor nozzles,
it could occur that at gun opening, a delay in the reset of the working pressure is revealed or a pulsation of the valve. To avoid such
inconveniences, it is necessary to guarantee always a pressure of at least 3-5 bar in the bypass line. This pressure can be obtained by
throttling the bypass line in one of the following ways:
ofitting in the bypass channel a 3/8” hose instead of 1/2"
ofitting in the bypass channel a rigid tube of a sufficiently small diameter
oinserting in the bypass channel a connector with an adequate orifice diameter
(available on request if not already included; see table)
In the case of feeding from the tank where also the bypass flow is discharged, it would be advisable to fit in the feed line of the machine
a low pressure pump that guarantees a feed pressure of the high pressure pump of 3-5 bar (See paragraph “EXAMPLES OF
INSTALLATION” Picture 4).
It is advisable that the tank be provided with deflectors to reduce eventual turbulence and air bubbles, generated by the intake of the
bypass flow, which could be harmful for the pump.
In the case of direct pump recycle of the bypass flow and if bypass conditions are foreseen frequently or for a long time, it is advisable to
fit a thermal protector valve (VT3 or VT6) in order to avoid dangerous overheating of recycled water.
PRESSURE ADJUSTMENT/SETTING
The desired working pressure must be adjusted while the system is in operation and the gun is opened. Adjust the pressure by screwing
or unscrewing the adjustment nut, taking care to lock the threaded piston with a second wrench, as shown in the picture.
The operation is easier if the correct nozzle has been chosen (see paragraph “installation”).
Pressure is increased by screwing the adjustment nut. In case pressure does not increase despite screwing of the nut, do not force,
but check that the nozzle flow rate/pressure ratio is correct.
Connector available on request
Flow (l/min)
Ø Bore (mm)
Thread
Part Number
9-15
2,7
G 3/8” M
60.2926.51
15-25
4.0
G 3/8” M
60.2927.51
25-35
4.5
G 3/8” M
60.2929.51
40
**
**
**

Ultimo aggiornamento: 15/11/19
4
EXAMPLES OF INSTALLATION

Ultimo aggiornamento: 15/11/19
5
TROUBLE SHOOTING
PROBLEMS
PROBABLE CAUSE
REMEDY
The valve is noisy.
Nozzle with very small flow factor (< 03).
Too much water in the bypass unloading.
Size the nozzle according to the flow of the
pump in order to decrease the water
unloading in the by-pass.
At gun opening much time is required to
reach working pressure.
Delivery hose very long or big level difference
between valve and gun.
Nozzle with very small flow factor (< 03)
Throttle bypass unloading.
See section:
DISCHARGE SYSTEM AND WATER
ADDUCTION
At gun closure the valve pulses (rearm).
Flow rate of the pump pulsating.
Check the pump.
Delivery hose too short.
Provide a longer hose.
The pump is sucking air in.
See section:
DISCHARGE SYSTEM AND WATER
ADDUCTION
At gun closure the valve pulses (rearm)
Big leakage from the gun
Leak from delivery line
Eliminate the leakage
At gun opening the valve does not go
under pressure and continues to
unloading into the bypass.
Delivery hose very long or big level difference
between valve and gun.
Nozzle with very small flow factor (< 03)
Throttle bypass unloading.
See section:
DISCHARGE SYSTEM AND WATER
ADDUCTION
At gun closure, the valve does not
lower the pressure on the delivery line.
Orifice of the shutter blocked
(pos.33 on exploded view).
Clean and eliminate obstruction.
Valve does not reach maximum
pressure.
Worn nozzle.
Replace
Presence of matter between seat and shutter
Clean the seat
Seat damaged or worn
Replace
Valve does not go into pressure.
O-rings of Sst piston (pos. 8-9-10 e 13-14-15 of
the exploded view ) ruined.
Replace
MAINTENANCE
STANDARD: every 400 working hours, check and lubricate the seals with water resistant grease.
SPECIAL: every 800 working hours, check the wear of the seals and internal parts and, if necessary, replace with original PA parts
taking care, during installation, to lubricate with water resistant grease.
The maintenance must be carried out by specialized technicians.
The manufacturer is not to be considered responsible for damage as a result from incorrect fitting and maintenance.
REGULATIONS
For a correct utilization, follow the directions as described in this manual and re-print them on the Use and maintenance of the machine.
If needed, ask for the original Conformity Declaration for the accessory chosen. The present manual is valid for all unloader valves
named VB 40/1000 Zero.
Technical data, descriptions and illustrations are indicative and liable for modification without notice.
Instruction manual, maintenance, installation, spare parts.
For a correct utilization, follow the directions of this manual and re-print them on
the Use and Maintenance booklet of the machine.
n. MPA.0004.EN

Last updated 20/10/2022
60.2900.00 VB40/1000 Zero Unload.-flow activated
Pos. P/N Description Q.ty K1K2K3K4 Pos. P/N Description Q.ty K1K2K3K4
1 60.2919.51R Sst seat, 9,5 mm 1 • 5
2 10.4013.00R Back-up ring, 16x13,2x1,2 mm 1 • 10
3 10.3060.85R O-ring, 1,78x12,42 mm HNbr 85 2 • 10
4 60.2925.51R Sst shutter v.2 1 • 5
5 10.4041.00R Back-up ring, 19,3x22x1,2 mm PTFE 1 • 10
6 10.3070.85R O-ring, 1,78x18,77 mm Hnbr 85 1 • 10
7 60.2906.51R 7 mm sst piston ring 1 3
8 10.4007.09R Back-up ring, 7x11,9x1,2 mm 1 • 10
9 10.4007.92R Back-up ring, 7x9x2 mm 1 • 10
10 10.3056.85R O-ring, 1,78x8,74 mm HNbr 85 1 • 10
11 60.2909.51R 7 mm sst piston ring 1 3
12 60.2924.51R Sst pin v.2 1 5
13 10.3072.85R O-ring, 1,78x21,95 mm HNbr 85 2 • 10
14 10.4059.00R Back-up ring, 20x22x2 mm 1 • 10
15 10.4059.09R Back-up ring, 20x24,9x1,2mm 1 • 10
16 60.2610.51R 9,2 mm sst piston ring 1 3
17 10.4055.00R Back-up ring, 9,2x11,2x2 mm 1 • 10
18 10.3058.85R O-ring, 1,78x10,82 mm HNbr 85 1 • 10
19 10.4008.09R Back-up ring, 9,2x14,1x1,2 mm 1 • 10
20 10.4098.00R Back-up ring, 23,2x26x1,2mm 1 • 10
21 60.2904.51R Lower plug, sst 1 3
22 60.2902.21R Sst. valve piston, VB40/1000 Zero 1 5
23 10.4161.00R Back-up ring, 18 mm 1 • 3
24 10.4013.09R Back-up ring, 13,1x18x1,2 mm 1 • 10
25 10.4060.09R Back-up ring, 20x22,8x1,2 mm 1 • 10
26 10.3072.95R O-ring, 1,78x20,35 mm Hnbr 85 1 • 10
27 60.2905.55R Housing -VB40/1000 Zero 3/8 .Bsp F sst 1 3
28 10.4008.93R Back-up ring, 9,3x14,2 x2,2 mm 1 • 5
29 10.3057.85R O-ring, 1,78x9,25 mm HNbr 85 1 • 10
30 10.4162.00R Back-up ring, 14,2 mm 1 • 3
31 60.2911.51R Sst. seat check valve 1 5
32 60.2931.21R Sst shutter+ nozzle M4 1 3
34 60.2601.51R Sst spring, 1,3x8,5x28,5 mm 1 10
35 10.3068.85R O-ring, 1,78x17,17 mm Hnbr 85 1 • 10
36 10.4099.00R Back-up ring, 17,2x20x1,2mm 1 • 10
37 60.2912.51R Shutter coupl., 3/8F Bsp sst 1 3
38 11.4629.00R Hex. nut, M10 2 10
39 60.2917.61R Hex. nut, M10 zpl. 1 5
40 60.2918.51R Washer, 10,3x25x0,5 Ai301 1 5
41 60.2914.51R Spring holding washer, sst 1 5
42 60.2901.61R Spring, 12x42x128 mm black 1 1
43 60.2915.51R Sst. M16x1 plug, ** 1 5
44 26.1046.84R Bushing, 10x14x7 mm Plast. ** 1 • 10
45 60.2903.51R Piston holder, sst 1 5
46 10.3014.25R O-ring, 1,5x2,5 mm Ni 70 1 10
** On request
Kit P/N Description
K1 60.2921.24 Spares kit -VB40/1000.Zero, 26x1pcs. 1