JET PUMP TECHNICAL DATA pumping liquids - …

1 Section 1000 bulletin 1200 Issued 5/87 Replaces 1/82 JET PUMP TECHNICAL data pumpingliquidsThis TECHNICAL bulletin includes general informationabout Penberthy Jet pumps plus specific details forselecting the proper unit. The two basic series ofPenberthy Jet pumps covered in this bulletin areused for pumping liquids jet pumps operateAll jet pumps operate on theprinciple of a fluid entraining asecond fluid. Although designand construction may vary,this applies to all jet jet pumps have threecommon features: inlet,suction, and discharge. Here ishow these function:Inlet The operating medium( liquid , gas, or steam) underpressure enters the inlet andtravels through the nozzle into thesuction chamber.

2 The nozzleconverts the pressure of theoperating medium into a highvelocity stream, which passesfrom the discharge side of the pumping action beginswhen vapor, gases, or liquid in thesuction chamber are entrained bythe high velocity stream emergingfrom the inlet nozzle, lowering thepressure in the suction resulting action causes theliquid, gas, or vapor in the suctionchamber to flow toward - The entrainedmaterial from the suction systemmixes with the operating mediumandacquires part of its energy in theparallel section. In the diffusersection part of the velocity of themixture is converted to a pressuregreater than the suction pressure,but lower than the operatingmedium advantages of using jetpumps for pumping liquidsPenberthy liquid Jet pumps offermany advantages:They have no moving parts,nothing to break or are no packing lubrication is are practically noiseless initial cost is cost is low becausethey are compact and nofoundation or wiring is provide reliable operationwith low maintenance pump applicationsThere are numerous possibleapplications for Penberthy JetPumps in handling liquids .

3 Jetpumps are commonly found inthese industries: chemical, textile,petroleum, power, mining,nuclear, fishing, wastewater,construction, distilling, applications include:handling condensate, pumpingwells, circulating solutions,emptying cesspools, pumpingbrine solutions, extractingsolvents, draining cellars, pumping out barges, acidifying,causticizing oils, producingemulsions, elevation and selectionJet Pump SelectionThere are two basic series of Penberthy Jetsavailable for pumping liquids . The L Series hasthree models, the LL, LM, and LH Models, usingliquid as the operating medium. The G Series hastwo models, the GL and GH, using steam as theoperating medium.

4 Each of the five models isavailable in 15 different sizes, from 1/2 inch to SERIES and G SERIES applicationsTYPICAL APPLICATIONSB lendingLifting or elevating liquidsBoosting suction pressure to centrifugal pumpLifting or elevating liquidsHandling granular solids with liquidsPenberthy L Series liquid -operated jets are available for low,medium and high availableEach model is available in 15sizes from 1/2 to 12 inchessuction and discharge. Units arecast construction in sizes 1/2through 4. Sizes 4 through 12 areavailable with fabricatedconstruction. Certain sizes ofunits are also available in PVC ormolded construction as shown inthe charts on page following information isneeded for selection: Temperatures of operatingand suction liquids .

5 Available operating liquidpressure PSIG (hm). Available volume ofoperating liquid GPM (Qm). Suction lift in feet of water(hs). Discharge head in feet ofwater (hd). Required pumping capacityGPM (Qs). Specific gravity of operatingliquid. Specific gravity of suctionliquid. Viscosity of operating liquid . Viscosity of suction liquid .*How to calculate NPSHIn the selection chart above, theoperating liquid is assumed to beat ambient temperature. Whenthe operating liquid is at highertemperatures or when the vaporpressure is other than that ofwater, the liquid may vaporizewithin the jet pump and reducepumping jet pumps , both motive andsuction liquids must beconsidered for purposes ofcalculating net positive suctionhead (NPSH).

6 Whichever liquidhas the higher vapor pressureshould be used as the basis of thecalculation. Both liquids will be atthe same temperature when theymeet at the jet center available is the dynamicpressure, in feet of liquid absolute,measured at the center line of thejet, less the vapor pressure. Itmust equal or exceed the NPSH that is required to achieve calculate NPSH for yourapplication us the followingformula:where:Ps = Pressure in the suction vessel in pounds per square inch absolute (PSIA).Pvp= Vapor pressure of the pumped liquid in Specific gravity of pumped liquid at pumping Feet that the fluid is below or above the jet pump center line (negative if below, positive if above).

7 Hf= Friction loss in the suction line (feet of liquid ).L series selectionfsGvpsHhSPPNPSH + =)( EXAMPLE CALCULATION:To pump water at 120 F with the surface of the water12 feet below the jet pump center line:Fluid Height (hs)..-12 Vessel Pressure (Ps).. PSIAV apor Pressure (Pvp).. PSIAF riction Loss (Hf)..1 footSpecific Gravity (SG).. the formula given above:1)12(988.) ( + =NPSHNPSH = feet of water absoluteThe feet of water supported by PSIA minusNPSH equals Suction Lift in feet:Suction Lift = ( ) feet of waterLLLow HeadLMMedium HeadLHHigh HeadOperating mediumLiquidLiquidLiquidOperating medium pressure range15-200 PSIG15-200 PSIG15-200 PSIGN ominal operating medium pressurePSIG/ft of discharge head2 PSIG(SG=1) PSIG(SG=1)1 PSIG(SG=1)Discharge head pressure rangeto 50 ft40 to 80 ft80 ft or moreSuction liftto 27 ftto 27 ftto 27 ftMinimum NPSH*3 ft3 ft3 ftModelL SERIES unit selection usingperformance chartsTo determine the correct jet, refer tothe performance charts on pages 6and 1 - Locate the Suction Lift (hs)nearest your 2 - Locate Discharge Head(hd).

8 Step 3 - The Operating WaterPressure shown (hm) represents theamount of suction (water) flow (Qs)for a 1 1/2 inch jet in each model(LL, LM, LH).Step 4 - Determine the amount ofOperating Water (Qm) for a 1 1/2inch jet in the three 5 - Choose unit with SuctionFlow GPM (Qs) and OperatingWater Used (Qm) matching , the unit selected shouldhave the greatest suction capacity(Qs) and consume the leastoperating liquid (Qm). Try all threemodels in other sizes as shown inthe example on page 4. (Theperformance charts are based on1 inch units).The effect of specific gravity andviscosity on Jet PumpperformanceFluid flow calculations indicate theeffects of viscosity and specificgravity in fluid flow systems, asdiscussed below.

9 The L Seriesperformance data on pages 6 and 7are based on water used asoperating and suction gravity of water is 1 andviscosity is 1 centipoise (cP).Viscosity of a fluid is a measure ofshearing stress within the fluid, anda factor in system flow rates andpressure drops. The effect ofviscosity on the performance ofPenberthy Jet pumps is negligiblefor viscosity values as high as 100cP. For higher viscosity values,consult the gravity of a liquid is the ratioof its weight per unit volume to theweight per unit volume of water atstandard conditions. Specificgravity values other than 1 will affectthe performance of Penberthy LiquidJet pumps , and require the followingadjustments:1.

10 Operating medium flow rate -rate shown in the performancecharts must be adjusted bymultiplying the table values by (1 SG) (the specific gravity ofactual operating fluid).2. Suction flow rate - Suction liftand Discharge Head are given infeet of fluid flowing and must beconverted to equivalent lift or headin terms of feet of water. Multiplythe given lift or head by the specificgravity of the fluid at that calculation purposes, theSuction Lift is multiplied by thespecific gravity of the suction equivalent Discharge Head iscalculated by averaging the specificgravity of the operating liquid flowand the suction flow. Multiply thataverage by the Discharge Head and vapor pressureproperties of liquids also affectperformance.