Universal Chargingand Testing UnitFPU-1For Bladder, Piston andDiaphragm Accumulators

1. DESCRIPTION1.1. FUNCTION

The charging and testing unitFPU-1 is used to chargeaccumulators with nitrogen or tocheck or to change the existingpre-charge pressure inaccumulators. For this purposethe charging and testing unit isscrewed onto the gas valve of thehydraulic accumulator andconnected to a commercialnitrogen bottle via a flexiblecharging hose. If the nitrogenpressure is only to be checked orreduced, the charging hose doesnot need to be connected.The unit has a screw-type fittingwith a built-in gauge, check valveand a spindle for opening theaccumulator gas valve to controlthe pressure.HYDAC piston and diaphragmaccumulators can be charged andchecked without the need foradaptors. Bladder accumulators,however, require an adaptor(A3 supplied as standard, seemodel code on page 2).

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2. TECHNICAL SPECIFICATIONS2.1. MODEL CODE

(also order example)FPU-1 250 F 2.5 G2 A1 K

Universal charging and testing unit

Gauge indication range0 - 10 bar 0 - 145 psi 100 - 25 bar 0 - 363 psi 250 - 100 bar 0 - 1450 psi 1000 - 250 bar 0 - 3626 psi 2500 - 400 bar 0 - 5714 psi 400

Charging hoseF = for 200 bar nitrogen bottle

with connection W24.32 x 1/14 (DIN 477, Part 1)FM = for 300 bar nitrogen bottle

with connection M30 x 1.5 (DIN 477, Part 5)FW = for 300 bar nitrogen bottle

with connection W30 x 2 (CEN)

Length of charging hose2.5 m 2.54.0 m 4Special lengths on request

Adaptor G for nitrogen bottlesSee table under point 10 (page 15)

Adaptor AA1 = M16 x 1.5A2 = 5/8 - 18 UNFA3 = 7/8 - 14 UNFA4 = 7/8 - 14 UNFA5 = M8 x 1A6 = G 3/4 AA7 = G 1/4A8 = G 3/4A9 = Vg 8A10 = 7/8 – 14 UNFA11 = M16 x 2D4 = 5/8 - 18 UNF(Material no. 366374)other adaptors on request

Protective case

Accessories (Please give full details when ordering.)Gas safety valve with intermediate piece (see point 5.3.).Pressure reducer (see point 5.1.).Adaptor for connector D (see point 4.1.).Wrench 14x15 (material no. 1011065).Allen key SW6 (material no. 1005164).Valve tool for gas valve (material no. 616886).

(A3 is supplied as standard)

1.2. INTERVALS BETWEENCHECKINGOn the whole, nitrogen losses onHYDAC hydraulic accumulatorsare very low. However, a regularcheck of the gas pre-chargepressure is recommended toprevent the piston from hitting thecover plate or the bladder ordiaphragm from becoming toodeformed, if there is a drop in thepressure p0.The pre-charge pressure p0 asshown on the label or theaccumulator body, must be re-setafter every new installation orrepair and then checked at leastonce during the following week.If no nitrogen loss is detected, afurther check should be madeafter approx. 4 months. If afterthis period no change in thepressure is found, a yearly checkshould be sufficient.

1.3. CONSTRUCTIONThe HYDAC charging and testingunit for bladder, piston anddiaphragm accumulators consistsof:Valve bodySpindleCheck valveRelease valveGaugeCharging hoseA3 adaptor for bladderaccumulators

1.4. ACCESSORIESGas safety valve withintermediate pieceTUV set and lead sealed, it mustbe fitted between the hydraulicaccumulator and the nitrogenbottle by means of theintermediate piece, if the gaspressure in the commerciallyavailable nitrogen bottle is higherthan the max. permissibleoperating pressure of thehydraulic accumulator.Pressure reducerfor setting the required pre-chargepressure between nitrogen bottleand accumulator.Protective casefor storing the charging andtesting unit and adaptors.

Different types of case areavailable, depending oncustomer requirement.

2.2. WEIGHTStandard model without case:approx. 1.4 kgStandard model with case:approx. 3.0 kg

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For pressures exceeding 400 bar,the following special models areavailable:FPS 600for bladder accumulators up to600 bar max. pre-charge pressure(see technical information293715).FPK 600for piston, diaphragm and SB800-1.5 accumulators up to 600 barmax. pre-charge pressure (seetechnical information 297248).FPH 800for high pressure bladderaccumulators up to 800 bar max.pre-charge pressure (seetechnical information 292948).

2.3. FPU-1 STANDARD MODELS2.3.1 Model without case

Model code Material no.FPU-1-010F2.5A3 2114486FPU-1-025F2.5A3 2114481FPU-1-100F2.5A3 2114310FPU-1-250F2.5A3 2114306FPU-1-400F2.5A3 2115646FPU-1-010F4A3 2115056FPU-1-025F4A3 2116876FPU-1-100F4A3 2115657FPU-1-250F4A3 2114311FPU-1-400F4A3 2119673

2.3.2 Model with case

Model code Material no.FPU-1-010F2.5A3K 2115365FPU-1-025F2.5A3K 2114305FPU-1-100F2.5A3K 2115314FPU-1-250F2.5A3K 2114302FPU-1-400F2.5A3K 2114307FPU-1-010F4A3K 3013690FPU-1-025F4A3K 2116738FPU-1-100F4A3K 2114842FPU-1-250F4A3K 2114303FPU-1-400F4A3K 2114304

2.3.3 Model without case with Gadaptor

Model code Material no.FPU-1-250F2.5G2A3 2120252FPU-1-250F2.5G3A3 2115555FPU-1-250F2.5G4A3 2124611FPU-1-250F2.5G9A3 2114312FPU-1-250F4G3A3 2123839FPU-1-250F4G6A3 2117532FPU-1-250F4G10A3 2119789FPU-1-400F2.5G2A3 2115823FPU-1-400F2.5G3A3 2121557FPU-1-400F2.5G8A3 2115693

2.3.4 Model with case and G adaptor

Model code Material no.FPU-1-010F2.5G2A3K 2116766FPU-1-010F2.5G3A3K 2127228FPU-1-010F2.5G4A3K 2125524FPU-1-010F2.5G6A3K 2115661FPU-1-010F2.5G7A3K 2117851FPU-1-010F2.5G8A3K 2117303FPU-1-010F2.5G9A3K 2114482FPU-1-010F2.5G10A3K 3008015FPU-1-010F4G7A3K 2124450FPU-1-025F2.5G2A3K 2114401FPU-1-025F2.5G3A3K 2121210FPU-1-025F2.5G4A3K 2115247FPU-1-025F2.5G5A3K 3013724FPU-1-025F2.5G8A3K 2119888FPU-1-025F2.5G9A3K 2123949FPU-1-025F2.5G10A3K 2119564FPU-1-025F4G9A3K 2119680FPU-1-100F2.5G2A3K 2122515FPU-1-100F2.5G4A3K 2122089FPU-1-100F2.5G6A3K 3003846FPU-1-100F2.5G9A3K 2119883FPU-1-100F4G3A3K 2120359FPU-1-250F2.5G2A3K 2114309FPU-1-250F2.5G3A3K 2114308FPU-1-250F2.5G4A3K 2103046FPU-1-250F2.5G5A3K 2117038FPU-1-250F2.5G6A3K 2115420FPU-1-250F2.5G7A3K 2120010FPU-1-250F2.5G8A3K 2115216FPU-1-250F2.5G9A3K 2115833FPU-1-250F4G2A3K 2116743FPU-1-250F4G3A3K 2116779FPU-1-250F4G4A3K 2128944FPU-1-250F4G8A3K 2124860FPU-1-250F4G9A3K 2116004FPU-1-250F4G10A3K 2125750FPU-1-400F2.5G2A3K 2114605FPU-1-400F2.5G3A3K 2115692FPU-1-400F2.5G4A3K 2128360FPU-1-400F2.5G5A3K 2124387FPU-1-400F2.5G6A3K 2121984FPU-1-400F2.5G8A3K 2116005FPU-1-400F2.5G9A3K 2115757FPU-1-400F4G2A3K 2122119FPU-1-400F4G3A3K 2115656FPU-1-400F4G7A3K 2124504FPU-1-400F4G8A3K 2119759FPU-1-400F4G9A3K 2126309FPU-1-400F4G10A3K 2116642

2.4. SPECIAL MODELS

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3. OPERATINGINSTRUCTIONS

3.1. TAKING ACCOUNT OF THETEMPERATURE EFFECTIn order that the recommendedpre-charge pressures aremaintained even at relatively highoperating temperatures, the pre-charge pressure p0 charge forcharging and testing a coldaccumulator must be selected asfollows:

p0 charge= p0 Pre-charge temp. + 273

Operating temp. + 273Pre-charge temperature [°C]Operating temperature [°C]

3.2. PREPARATIONPrior to each testing, topping-upor re-charging of nitrogen, theaccumulator must be isolatedfrom the pressurised system bymeans of a shut-off valve and thefluid released.Unscrew the protective caps Sand H (only on bladderaccumulators). Remove theO-ring O on bladder accumulators.Slightly loosen the internalhexagon screw P on piston anddiaphragm accumulators bymeans of an Allen key SW 6,DIN 911 (approx. ½ turn).Place FPU-1 onto theaccumulator and screw connectorD by hand onto accumulator gasvalve. At the same time, ensurethat the release B of theFPU-1 is closed. Turn chargingunit to a position where the gaugecan be easily read.

3.3. TESTINGOn bladder accumulators(FPU-1 with A3 or other suitableadaptor) open valve by turningspindle A clockwise.On piston and diaphragmaccumulators (FPU-1)open valve V by turning theinternal hexagon screw anti-clockwise with spindle A.When the needle of the gaugebegins to move, give the spindleanother complete turn.The gauge now shows thecharging pressure in theaccumulator. The check valve Cprevents any escape of nitrogen.

3.4. REDUCING THE PRE-CHARGEPRESSURECarefully open release B.The nitrogen escapes into theatmosphere.

Allen keySW 6DIN 911

Charging and testing unit FPU-1 forpiston and diaphragm accumulators

Charging and testing unit for bladderaccumulators with adaptor A3

Gas valve for piston and diaphragmaccumulators

Gas valve for bladder accumulators

A

A

B C

B C

D A3

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3.6. FPU-1 WITH ACCESSORIES

adaptor G

pressure reducer

G 1 M

charging and testing unit FPU-1

nitrogen bottlehydraulicaccumulator

adaptor A

3.5. INCREASING PRE-CHARGEPRESSUREOnly use nitrogen forcharging accumulatorsNever use oxygen!Danger of explosion!If the gas pressure in thenitrogen bottle is higher thanthe max. operating pressure ofthe accumulator, a gaspressure reducer must befitted.Connect the flexible charginghose to the pressure reducer onthe nitrogen bottle by means ofthe connector G1.For nitrogen bottles from othercountries the appropriate adaptoris required (see page 15).Connect connector M of thecharging hose to the check valveC of the charging and testing unitFPU-1. Open the shut-off valveon the nitrogen bottle, and slowlyrelease nitrogen into theaccumulator. Wait untilapproximately 1 bar has beenreached before opening the shut-off valve of the nitrogen bottlefurther to enable faster charging.Interrupt the charging processfrom time to time and check thepre-charge pressure reached.Repeat this process until therequired gas pre-charge pressureis achieved. After temperatureequalisation has taken place,re-check the pre-charge pressureand adjust if necessary. If thepressure is too high, it can belowered via the pressure releaseB of the FPU-1.If the required gas pre-chargepressure has been reached, turnthe spindle anticlockwise to closethe gas valve on bladderaccumulators. On piston ordiaphragm accumulators closethe internal hexagon screw P byturning the spindle clockwise.Discharge the charging andtesting unit FPU-1 via thepressure release and remove it byloosening the connector. Onbladder accumulators, unscrewthe adaptor and replace theO-ring O. On piston anddiaphragm accumulators, tightenthe internal hexagon screw P withAllen key [20 Nm].Check for leakages on theaccumulator gas valve using aleak detector spray.Screw on cap nut H (only onbladder accumulators) and valveprotection cap S onto the gasvalve of the accumulator andtighten.

charging hose

3.7. WARNINGNitrogen and operating fluid canescape when filling or testing theaccumulator due to a faulty, i.e.leaking, bladder, diaphragm orpiston seals.Caution!Risk to health in the case ofaggressive fluids!(special charging and testing unitavailable on request)The check valve C must not bedismantled. The valve has asafety function for the wholecharging and testing unit.

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4. DIMENSIONS4.1. CHARGING AND TESTING UNIT FPU-1 WITH ADAPTOR FOR HYDAC ACCUMULATORS

Bladder accumulator330-0.5 / 400-0.5

Bladder accumulator≥ 1l

Gas valve toISO 10945

Piston anddiaphragmaccumulator

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4.2. CHARGING HOSE F(200 bar nitrogen bottle - connection to DIN 477, part 1)

Length Material no. 2.5 m 236514 4.0 m 23651510.0 m 37340515.0 m 211555220.0 m 210976528.0 m 2109574

4.3. CHARGING HOSE FM(300 bar nitrogen bottle - connection to DIN 477, part 5)

Length Material no. 2.5 m 3019417 4.0 m 3019418

4.4. CHARGING HOSE FW(300 bar nitrogen bottle - connection to CEN)

Length Material no. 2.5 m 3019419 4.0 m 3019420

Charging hoses are suitable for therespective published maximumpermissible operating pressures and10,000 charging processes.(HYDAC charging hoses comply withthe EC machine directive and withDIN EN 982 and DIN EN 853 to 857).

knurling

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A1 (Material no. 361619)

A2 (Material no. 361605) A5 (Material no. 291531)

A4 (Material no. 291536)

A3 (Material no. 291533) A6 (Material no. 2108819)

4.5. ADAPTORS A1 TO A11The universality of the FPU-1 isguaranteed because as well asHYDAC piston and diaphragmaccumulators, bladderaccumulators can also becharged and tested using the A3adaptor.By using additional adaptors othermakes of accumulator can also becharged and tested.

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G 7 (Material no.236377)

G 9 (Material no. 241168)

G 10 (Material no. 2103427)

G 8 (Material no.2103425)

seal ring A 6 x 10

4.6. ADAPTORS G2 TO G11

G 11 (Material no. 3018678)

G 2 (Material no. 236376)

G 3 (Material no. 2103421)

G 6 (Material no. 2103423)

G 4 (Material no. 236374)

seal ring A 6 x 10

seal ring A 6 x 10

seal ring A 6 x 10

seal ring A 6 x 10

G 5 (Material no. 236373)

seal ring A 6 x 10

A7 (Material no. 2110629)

A8 (Material no. 2124524)

A9 (Material no. 2128638)

A10 (Material no. 2128849)

A11 (Material no. 3018210)

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5. ACCESSORIES5.1. PRESSURE REDUCER FOR 200 BAR NITROGEN BOTTLES

(Connection W24.32 x 1/14 - DIN 477, Part 1)

Bottle pressure Reduces pressure[bar] to between [bar] Material no.200 0- 20 635409200 0-100 635411200 0-200 635412Weight: 2.3 kg

5.2. PRESSURE REDUCER FOR 300 BAR NITROGEN BOTTLES(Connection W30 x 2 - CEN)

Bottle pressure Reduces pressure Connection H Material no.[bar] to between [bar]300 0 - 20 W24.32x1/14 6004020300 0-100 W24.32x1/14 6004021300 0-200 W24.32x1/14 6004022Weight: 2.3 kg

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5.3. GAS SAFETY VALVE GSV6

Q [kg/h] p [bar] Mat. no.15 30 312396520 40 312396628 50 312396735 60 312402840 70 312402945 80 312403050 90 312403158 100 312403265 110 312403370 120 312403475 130 312403583 140 312403688 150 312403795 160 3124038100 170 3124039105 180 3124040110 190 3124041118 200 3124042125 210 3124043130 220 3124044135 230 3124045140 240 3124046148 250 3124047155 260 3124048160 270 3124049165 280 3124050170 290 3124051178 300 3124052185 310 3124053190 320 3124054195 330 3124055200 340 3124056205 350 3124057210 360 3153706216 370 3143015others on request> 350 bar = additional price for EC

individual testing

Steel/elastomersealing ring

TÜV / HYDAC seal

hex. 32

GSV6 - 10 - 0034EN ISO 4126-1.6.G.195 KG/H 330 BARTS -20/80 °C PS 370 BAR 14/03/452

5.3.1 Model code(also ordering example)

GSV6 - 10 - CE0034.ENISO4126-1.6.G. 195. 330

Gas safety valve

Component code

Flow rate Q in kg/h(see table, point 5.3.2)

Pressure setting p in bar(see table, point 5.3.2)

5.3.2 Types of GSV6 5.3.3 Type of constructionDirect-acting gas safety valvenominal width 6 mm

5.3.4 DesignPED 97/23/EC,EN ISO41236-1, EN 13445-6Others on request

5.3.5 Module categoryIV to PED 97/23/ECModule B + D (EC prototype test)module G (EC individual test)on request

5.3.6 Materialsstainless steel,closing element with flexibleseat seal

5.3.7 Operating pressure range30 to 370 bar

5.3.8 Temperature range-20 to +80 °C

5.3.9 Operating fluidNitrogen (N2)

5.3.10 Mounting positionoptional

5.3.11 Weight1.1 kg

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6. CHARGING AND TESTING BLOCK F + PThe HYDAC charging and testing block F+P is used to charge and testback-up type hydraulic accumulators. It has connections for the chargingand testing unit FPU-1 and for pressure gauges. As a safety function,a gas safety valve GSV6 can be fitted. In addition it allows the back-upnitrogen bottles to be shut off from the hydraulic accumulator.

6.1. BACK-UP TYPE HYDRAULIC ACCUMULATOR WITH CHARGINGAND TESTING BLOCK

nitrogen bottles

hydraulicaccumulator

safety andshut-off block

charging and testing block

connection for gas safety valve

connection for charging and testing unit FPU-1

5.4. INTERMEDIATE PIECE GSV6-10-CEIntermediate piece for fitting the gas safety valve GSV6 between the200 bar nitrogen bottle and the charging and testing unit FPU-1(material no. 242558)

Weight: 0.5 kg

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6.2. CHARGING AND TESTING BLOCK DN 16

F+P-16-20SR-6112-02X (Material no. 850233)(max. operating pressure 400 bar)

Weight: 4.3 kg

charging and testing unitM28 x 1.5

4 mounting holes

hydraulicaccumulator

nitrogen bottle

gas safety valveGSV6 (optional)

connection forpressure gauge(optional)

connection forpressure gauge(optional)

6.3. CHARGING AND TESTING BLOCK DN 32

F+P-32-38SR-6112-02X (Material no. 552193)(max. operating pressure 350 bar)

Weight: 14.0 kg

charging and testing unitM28 x 1.5 4 mounting holes

hydraulicaccumulator

nitrogen bottle

gas safety valveGSV6 (optional) connection for

pressure gauge(optional)

connection forpressure gauge(optional)

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7. SPARE PARTSCHARGING AND TESTING UNIT FPU-1Item Quantity Designation Material no.1 1 O-ring 6 x 1 601 0322 1 Seal ring 612 7303 1 Pressure 0 - 10 bar 635 139

gauge 0 - 25 bar 635 1400 - 100 bar 635 1410 - 250 bar 635 1420 - 400 bar 635 143

5 1 O-ring 15 x 2 601 0496 1 Seal ring 601 4567 1 O-ring 11 x 2 601 0438 1 O-ring 9 x 2 601 0409 1 O-ring 11 x 2.5 603 681

10 1 O-ring 5.7 x 1.9 6004009Seal kit FPU-1 2117669

GAS SAFETY VALVE GSV6-10-CEItem Quantity Designation Material no.11 Seal ring 21.54 x 28.58 x 2.47 6018877When mounting onto the HYDAC charging and testing block, O-ring 18 x 2.5(Material no. 601 057) must be fitted.

INTERMEDIATE PIECE GSV6-10-CEItem Quantity Designation Material no.12 2 O-ring 20 x 2.5 601 05813 1 Seal ring 20 x 11.5 x 2 614 70614 1 Seal ring 14 x 8.5 x 2 612 735

Seal kit intermediate piece 2117287

CHARGING AND TESTING BLOCKSeal kit F+P DN 16 2115776Seal kit F+P DN 32 2112088

HYDAC nitrogen charging unitsfacilitate fast and cost-effectivefilling or testing of the requiredgas pre-charge pressure inbladder, diaphragm or pistonaccumulators. They guaranteeoptimum use of commerciallyavailable nitrogen bottles up to aresidual pressure of 20 bar and amaximum accumulator pressureof 350 bar. Portable, mobile andstationary types of N2 Server areavailable. For further details andtechnical specifications, seeHYDAC brochure "NitrogenCharging Unit N2 Server",no.: E 2.201.

9. NOTEThe information in this brochurerelates to the operating conditionsand applications described.For applications or operatingconditions not described, pleasecontact the relevant technicaldepartment.Subject to technical modifications.

8. NITROGEN CHARGINGUNIT