VB 60/ Zero Flow sensitive unloader valve

Transcription

1 Ultim aggirnament: 20/04/18 VB 60/ Zer Flw sensitive unlader valve Manuale tecnic: E 272 Pressure regulating valve unlader type with zer setting n delivery line: at gun clsure the water flw is bypassed at lw pressure maintaining als the delivery line in lw pressure. DN VB 60/600 Zer (A: black spring) G 1/2 FF VB 60/400 Zer (B:blue spring + spacer) G 1/2 FF VB 60/250 Zer (C: white spring + spacer) G 1/2 FF Near ttal zer setting f the pressure in the delivery line at gun clsure. Advantages: Increased safety fr the peratr. Delivery hse easy t cntrl when gun is clsed. Less frce needed t repen the gun. At gun repening, wrk pressure is reached gradually. Advantages: Operatrs wrk less heavy. Easy starting if thermal engine is used. Reduced pressure lss and hardly dependent n flw rate. Great reliability. Easy maintenance. Three versins with different wrking pressure but ne sle range f flw rate frm 9 up t 60 l/min. TECHNICAL SPECIFICATIONS Cnstructin material: Sst. PART NUMBER MINIMUM FLOW MAXIMUM FLOW PERMISSIBLE PRESSURE ADJUSTABLE MINIMUM PRESSURE MAX TEMPERATURE (1) WEIGHT INLET OUTLET BYPASS l /min USG l / min USG bar psi bar psi C F g lbs G 1/2 F G 1/2 F G 1/2 F 1) The valve has been designed fr a cntinuus use at a water temperature f 60 C (140 F). It can wrk fr shrt perids at a maximum temperature f 90 C (195 F). 1

2 Ultim aggirnament: 20/04/18 DIMENSIONAL DRAWING SELECTION This prduct is intended t be incrprated n a finished machine. This prduct is t be utilized with clean fresh water, even slightly additivated with nrmal detergents. Fr use invlving different r crrsive liquids, cntact the PA Technical department. Apprpriate filtratin shuld be installed when using unpure liquids. Chse the valve in line with the wrking data f the machine where t be installed (permissible pressure, maximum flw and rated temperature f the system). In any case, the pressure f the machine must nt exceed the permissible pressure imprimed n the valve. Attentin. The VB60/ Zer valve is sensitive t water flw : at gun pening (water flw thrugh the valve) the system ges int pressure, at gun clsure (flw interruptin) the system wrks at lw pressure. Fr this reasn the Pulsar zer valve cannt be installed n systems that fit always weeping antifreeze systems. Instead it can be installed n systems with antifreeze systems weeping at lw pressure. In this case it is necessary t create in the bypass line a pressure higher than the pressure at which the antifreeze system becmes weeping. OPERATIONS The valve regulates the maximum pressure f the system by variating the flw discharged by the bypass. The adjustment is made by altering, by means f a pistn, the psitin f a sphere which clses partially the bypass pening. The valve is sensitive t water flw. At gun pening, the water flws thrugh the valve which maintains the system in pressure. At gun clsure, the interruptin f the flw prvkes the cmplete aperture f the bypass which allws t discharge the flw at lw pressure. At gun clsure, the special mechanism f zer setting patented by PA, which des nt includes a check valve, keeps in cnnectin the delivery line and the bypass line, in that way permitting t lwer the pressure all arund the system and nt nly in the surce line f the valve. 2

3 Ultim aggirnament: 20/04/18 INSTALLATION This accessry, n a system that prduces ht water, must be fitted upstream the heat generatr. On a system that generates ht water, it is advisable t fit in accessries that limit the accidental increase f fluid temperature. D nt install the valve n the pump head: secure the valve t the machine s frame by means f the fixing hles btained n the bdy. In this way the valve is subject t less vibratins, reducing therefre the wearing f the internal parts. Always install a safety valve. We recmmend the use f a nzzle with flw rate which allws a regular discharge frm the valve bypass f at least 5% f the flw supplied by the pump, in rder t achieve a cnstant pressure value and easy adjustment. If the nzzle wears ut, the pressure decreases. T reset pressure back at wrk level, it is necessary t replace the wrn nzzle. When a new nzzle is fitted, re-setting f the system t its riginal wrking pressure is required. DISCHARGE SYSTEM AND WATER ADDUCTION The valve can be fitted n machines fed directly by the water system with bypass recycle t the pump r n machines fed by a tank where the bypass flw is als discharged. In certain cnditins, depending n installatin and in particular: thrugh feeding frm tank, with lng delivery lines r strng difference in level, with lw flw rate and small flw factr nzzles, it culd ccur that at gun pening, a delay in the reset f the wrking pressure is revealed r a pulsatin f the valve. T avid such incnveniences, it is necessary t guarantee always a pressure f at least 3-5 bar in the bypass line. This pressure can be btained by thrttling the bypass line in ne f the fllwing ways: fitting in the bypass channel a 3/8 hse instead f 1/2" fitting in the bypass channel a rigid tube f a sufficiently small diameter inserting in the bypass channel a cnnectr with an adequate rifice diameter inserting in the bypass cnnectin (Picture 1) a washer with an adequate rifice diameter (available n request; see chart) inserting in the bypass cnnectin (Picture 2) the STR adjustable restrictr ( p.n available n request). Available washers n request Flw l/min (USGpm) Ø rifice mm Cnnectr cde thread SPECIAL 2.5 Bsp (2.5 4) 3 Bsp (4 8) 4.5 Bsp Picture 1 Picture 2 In the case f feeding frm the tank where als the bypass flw is discharged, it wuld be advisable t fit in the feed line f the machine a lw pressure pump that guarantees a feed pressure f the high pressure pump f 3-5 bar (See paragraph EXAMPLES OF INSTALLATION Picture 4). It is advisable that the tank be prvided with deflectrs t reduce eventual turbulence and air bubbles, generated by the intake f the bypass flw, which culd be harmful fr the pump. In the case f direct pump recycle f the bypass flw and if bypass cnditins are freseen frequently r fr a lng time, it is advisable t fit a thermal prtectr valve (VT3 r VT6) in rder t avid dangerus verheating f recycled water. 3

4 Ultim aggirnament: 20/04/18 EXAMPLES OF INSTALLATION 4

5 Ultim aggirnament: 20/04/18 PRESSURE ADJUSTMENT/SETTING The desired wrking pressure must be adjusted while the system is in peratin and the gun is pened. Adjust the pressure by screwing r unscrewing the adjustment nut. The peratin is easier if the crrect nzzle has been chsen (see paragraph installatin ). Pressure is increased by screwing the adjustment nut. In case pressure des nt increase despite screwing f the nut, d nt frce, but check that the nzzle flw rate/pressure rati is crrect. TROUBLE SHOOTING PROBLEMS PROBABLE CAUSE REMEDY At gun pening much time is required t reach wrking pressure At gun pening the valve pulses At gun clsure the valve pulses (rearm) Delivery hse very lng r big level difference between valve and gun Nzzle with very small flw factr (< 03) Pump feed frm tank Delivery hse very lng r big level difference between valve and gun Nzzle with very small flw factr (< 03) Pump feed frm tank Flw rate f the pump pulsating Big leakage frm the gun Leak frm delivery line Thrttle bypass line Thrttle bypass line Check the pump r install a pulsatin dampener Repair the gun t eliminate leakage Eliminate the leakage At gun clsure, the valve des nt lwer the pressure n the delivery line Valve des nt reach maximum pressure Valve des nt g int pressure Orifice f the shutter blcked (ps.33 n explded view) Wrn nzzle Seat damaged r wrn Presence f matter between seat and shutter O-rings f Sst pistn ( ps. 2-5 e f the explded view ) ruined Clean and eliminate bstructin Replace Replace Clean seat Replace MAINTENANCE STANDARD: every 400 wrking hurs, check and lubricate the seals with water resistant grease. SPECIAL: every 800 wrking hurs, check the wear f the seals and internal parts and, if necessary, replace with riginal PA parts taking care, during installatin, t lubricate with water resistant grease. The maintenance must be carried ut by specialized technicians. The manufacturer is nt t be cnsidered respnsible fr damage as a result frm incrrect fitting and maintenance. REGULATIONS Fr a crrect utilizatin, fllw the directins as described in this manual and re-print them n the Use and maintenance f the machine. If needed, ask fr the riginal Cnfrmity Declaratin fr the accessry chsen. The present manual is valid fr all unlader valves named VB 60/ Zer. Technical data, descriptins and illustratins are indicative and liable fr mdificatin withut ntice. Instructin manual, maintenance, installatin, spare parts. Fr a crrect utilizatin, fllw the directins f this manual and re-print them n the Use and Maintenance bklet f the machine. n

6 VB60/600 Zer Unlad.-flw activated 1/2Bsp VB60/250 Zer Unlad.-flw activated 1/2Bsp VB60/400 Zer Unlad.-flw activated 1/2Bsp Ps. P/N Descriptin Q.ty K1K2K3K4 Ps. P/N Descriptin Q.ty K1K2K3K Back-up ring, 23,2x26x1,2mm O-ring, 1,78x21,95 mm Ni O-ring, 1,78x10,82 mm Back-up ring, 9,2x11,2x2 mm Back-up ring, 20x22x2 mm Sst seat, 8,5 mm O-ring, 1,78x12,42 mm Ni Back-up ring, 16x13,2x1,2 mm Shutter pin, M6 sst+ball, 13/32" mm sst pistn ring O-ring, 1,78x8,74 mm Back-up ring, 7x9x2 mm Back-up ring, 19,3x22x1,2 mm PTFE O-ring, 1,78x18,77 mm Ni Spacer ring 7 mm Sst pin ,2 mm sst pistn ring Lwer plug, sst Pin, 3,1x18 mm Sst Pistn hlder, sst Bushing, 10x14x7 mm Plast Sst. valve pistn Back-up ring, 17,2x20x1,2mm O-ring, 1,78x17,17 mm Ni ** On request Back-up ring, 18 mm O-ring, 1,78x12,42 mm Back-up ring, 14,2 mm O-ring, 1,78x9,25 mm Set screw, DIN915 M6x10 mm Sst Husing -VB60/600 Zer, 1/2.Bsp F sst Sst shutter Sst spring, 1,3x8,5x24 mm (1,2) Sst spring, 1,3x8,5x28,5 mm (3) Shutter cupl., 1/2F Bsp sst Hex. nut, M Hex. nut, M Spring hlding washer, sst (3) Spring hlding washer, sst Spring, 8,5x38x80 mm black (3) Spring, 6,5x33x70 mm white (1) Spring, 7,5x35x70 mm blue (2) Nzzle, 2,5 mm brass ** Nzzle, 3,0 mm brass ** Nzzle, 4,5 mm brass x1/2 Bsp ** Spare kit seat/check valv.pcs.2x1 ** Seal frame >VB60-80 zer ** Seal frame >VB60-80 zer ** 1 1 Kit P/N Descriptin K Spares kit -VB60/600.Zer, 20x1pcs. 1 (1) (2) (3) Last updated 11/05/2018

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8 P.A. S.p.A. Via Milan, Rubiera, Reggi Emilia - Italy Tel Fax inf@pa-etl.it COMPANY WITH QUALITY MANAGEMENT SYSTEM CERTIFIED BY DNV ISO 9001