TWIN SCREW PUMPS Lucca, 15 June 2016 1
TABLE OF CONTENT 2
1) INTRODUCTION TO THEORY OF TWIN SCREW PUMPS 2) FEATURES AND ADVANTAGES 3) BASIC EXECUTIONS 4) APPLICATION FIELDS 5) 3P PRINZ TWIN SCREW PUMP RANGE 6) 3P PRINZ MODEL DE-CODIFICATION 7) MATERIALS SELECTION 8) SIZING OF TWIN SCREW PUMPS 9) FLUIDS HANDLED 10) NPSHr AND SUCTION LIFT 11) PUMP EXECUTIONS FOR THE MAIN SECTORS 12) CRITICAL APPLICATIONS 13) PERFORMANCE TEST STANDARDS 14) API 676 COMPLIANCE AND DEVIATIONS 3
PERA-PRINZ TWIN SCREW PUMPS SINGLE AND DOUBLE END POSITIVE DISPLACEMENT PUMPS Series HM HR HD UD JD SR SD The PERA-PRINZ Screw Pumps are Rotating Positive Displacement Pumps, externally or internally supported. One or Two Pairs of Screws, which operate without being in contact with each other, ensure a constant flow, pulsation-free, together with a high suction lift capability with very low NPSH values. Horizontal Installation is supplied as standard while Vertical Installation is supplied on request. External supports and gears is supplied as Standard while Internal supports and gears can be supplied on request, in case the pumped fluid is sufficiently clean and lubricating. 4
PERA-PRINZ TWIN SCREW PUMPS WORKING PRINCIPLE The Screws Pair rotates inside the Pump Enclosure, creating several separate chambers and pushing the fluid trapped inside in accordance with the progression of the screws pitch. The flow rate is particularly uniform and pulsation-free, and the pumped fluid flows in an axial direction (not circumferentially, as it happens in the centrifugal pumps). Fluids that are sensitive to shear forces or turbulent flows are subject only to very limited stresses during the pumping phase: Thanks to the absence of pulsations, to the low flow internal velocities, to the minimization of the centrifugal movements and to the absence of contact between the screw rotors, the pumped product does not suffer of changes of volume, texture, aspect and properties. Thanks to the low inertia of the rotating parts, the Screw Pumps can work at rotating speeds higher than other Positive Displacement Pumps of equivalent volume chambers. 5
PERA-PRINZ TWIN SCREW PUMPS WORKING PRINCIPLE Timing Gears 2 Opposite Screws mounted on 1 Shaft Bearings 6
PERA-PRINZ TWIN SCREW PUMPS EXECUTIONS BY APPLICABLE STANDARD: Manufacturer Standard API 676 BY MOUNTING: Overhung Twin Screws / Single Volute (Single End) / Single Pair of Screws Between Bearing Twin Screws / Double Volute (Double End) / Double Pair of Screws Only the Radial Loads are balanced on the Single Volute Twin Screw Pumps. The Radial and Axial Loads are balanced on the Double Volute Twin Screw Pumps. 7
PERA-PRINZ TWIN SCREW PUMPS EXECUTIONS BY INSTALLATION: Horizontal Shaft (Side Top Flanges) Vertical Shaft (Side Side Flanges) Horizontal Shaft (Side Side Flanges) 8
PERA-PRINZ TWIN SCREW PUMPS EXECUTIONS BY LINER: Non-Replaceable Liner - Cast Body Replaceable Liner Welded Fabricated Steel Body 9
PERA-PRINZ TWIN SCREW PUMPS ADVANTAGES Self Priming They ensure a constant flow, pulsation-free High Suction Lift Capability the pump NPSH being very low Suitable to pump fluids with low, medium, high and very high viscosity. Very well suited to pump very viscous liquids, sensitive to shear forces and turbulences thanks to the low Internal velocities given by the screws movement. Low Noise Level and Low Vibrations The Screws are Contactless and Wear out is minimized 10
PERA-PRINZ TWIN SCREW PUMPS ADVANTAGES ON TANK STORAGE CENTRIFUGAL PUMPS FOR TANK STORAGE: - Capable of pumping fluids only up to approximately 150 cst - Generate pressure in accordance to their characteristic Curve - Not well suitable to variable speed operation TANK STORAGE PRODUCTS OFFLOADING PUMP 1 BB1 Centrifugal Pump: 1500 m3/h @ 100 mwc Max 150 cst CRUDE OIL CARRIER PUMP 2 BB1 Centrifugal Pump: 800 m3/h @ 100 mwc Max 150 cst OIL TANK BARGE PUMP 3 OH1 Centrifugal Pump: 150 m3/h @ 100 mwc Max 150 cst OIL TRUCK - RAILCAR 11
PERA-PRINZ TWIN SCREW PUMPS ADVANTAGES ON TANK STORAGE TWIN SCREW PUMPS FOR TANK STORAGE: Capable of Operating at High Angular Speeds thanks to the screws low inertia, allowing a high range of flow rates if the pumps are driven by a Variable Speed Drive or by an Inverter Constant Flow regardless pressure changes (in particular when viscous fluids are pumped) Capability of handling a Wide Range of viscosities and pressures TANK STORAGE PRODUCTS OFFLOADING 1500 m3/h @ 100 mwc Max 500 cst CRUDE OIL CARRIER 800 m3/h @ 100 mwc Max 1000 cst OIL TANK BARGE ONE PUMP FOR ALL SERVICES ONLY ONE INSTALLATION: 150 m3/h @ 100 mwc Max 2000 cst OIL TRUCK - RAILCAR Less installation costs Less pipe work 12
PERA-PRINZ TWIN SCREW PUMPS ADVANTAGES Flow can be reversed (reversibility) in low pressure applications, upon request Entrapped Air or Gas in the Liquid are tolerated up to 50-60% volume (multi-phase service on request) Capability of Dry Running for a limited period and in particular conditions Compact Design and Dimensions 13
PERA-PRINZ TWIN SCREW PUMPS GENERAL FEATURES AND PERFORMANCES CAPACITY: from 1 m3/h up to 3.500 m3/h [from 4.5 GPM up to 15,500 GPM] CASING PRESSURE: up to ANSI 900-149 barg [2160 Psig] DIFFERENTIAL PRESSURE: up to 60 bar [870 Psi] NPSHr: down to 1,5 meters [5 ft] VISCOSITIES: from 0,5 cst up to 50.000 cst (up to 250.000 cst in special execution) PUMP NOISE LEVEL: up to 85 db for small and medium sizes GAS/AIR HANDLING: Gas/Air Content up to 50% (dissolved, not slug) TEMPERATURE: up to 300 C [573 F] 14
PERA-PRINZ TWIN SCREW PUMPS MAIN APPLICATIONS OIL & GAS UPSTREAM OIL FIELDS OFFSHORE PLATFORMS FPSOs & FSOs FLUIDS HANDLED: - CRUDE OIL (RAW OR REFINED) - CRUDE OIL MIXED WITH WATER - CRUDE OIL MIXED WITH WATER AND GAS - ALL TYPE OF HYDROCARBONS, LIGHT AND HIGH VISCOSITY (FROM GASOLINE TO BITUMEN) - OIL / WATER EMULSIONS, INCLUDING SLOPS, PRODUCED WATER - CHEMICALS (METHANOL, INHIBITORS) 15
PERA-PRINZ TWIN SCREW PUMPS MAIN APPLICATIONS OIL & GAS MIDSTREAM DOWNSTREAM OIL PIPELINE OIL TANKER / BARGE REFINERY PETROCHEMICAL PLANTS TANK STORAGE TERMINALS FLUIDS HANDLED: - CRUDE OIL (RAW OR REFINED) - CRUDE OIL MIXED WITH WATER - CRUDE OIL MIXED WITH WATER AND GAS - ALL TYPE OF HYDROCARBONS, LIGHT AND HIGH VISCOSITY (FROM GASOLINE TO BITUMEN) - OIL / WATER EMULSIONS, INCLUDING SLOPS, PRODUCED WATER - CHEMICALS (METHANOL, INHIBITORS) 16
PERA-PRINZ TWIN SCREW PUMPS MAIN APPLICATIONS MARINE & SHIPBUILDING FLUIDS HANDLED: - CRUDE OIL - ALL TYPE OF HYDROCARBONS, LIGHT AND HIGH VISCOSITY: - GASOLINE - DIESEL / NAPHTA - LUBE OIL - HEAVY FUEL OIL / MAZOUT - BITUMEN / ASPHALT / TAR - OIL / WATER EMULSIONS, INCLUDING SLOPS - TANK STRIPPING FOR ALL FLUIDS OIL TANKERS BARGES CARRIERS CRUISE SHIPS NAVY SHIPS SUPPORT VESSELS 17
PERA-PRINZ TWIN SCREW PUMPS MAIN APPLICATIONS OTHER APPLICATION FIELDS Power Plants Light and Heavy Liquid Fuels Fuel Burner Oils Lube Oil Dairy Products (Yogurt, Cream) Fruit Juices, Pastes, Jam Syrups and Molasses Food & Beverage and Pharmaceutical Chemical Industry General Industry Vegetable and Animal Oils / Fats Pastes Processed Meat Alcohol / Liquors Chocolate Caramel and Fudge Sauces / Concentrates Dough Beer and Wines Acids and Concentrated Acids Solvents Lubricating Oils Aliphatic Acids Additives Wax Glycerin Latex Lye Glues Alkaline Solutions Emulsions Soaps Caustic Soda Solvents Liquid Sulfur Rubber Suspensions Paraffin Polymers / Fibers Suspensions Polyester Resins Colouring & Pigmented Pastes Thickeners Additives Enamels and Paints Emulsions Hydraulics 18
PERA-PRINZ TWIN SCREW PUMPS SERIES TWIN SCREW PUMP CAPACITY RANGE DESIGN PRESSURE MARKET HM Series HR Series HD Series UD Series Single Pair of Screws, External Timing Gears up to 80 m3/h 20 Bar Oil&Gas, Industrial, Marine Double Pair of Screws, Light & Compact Design, External Timing Gears up to 3500 m3/h 14 Bar Oil&Gas, Industrial, Marine Double Pair of Screws, Heavy Duty Design, External Timing Gears up to 3500 m3/h 25 Bar Oil&Gas, Industrial, Marine Double Pair of Screws, High Pressure Design, External Timing Gears up to 1000 m3/h 50 Bar Oil&Gas, Industrial, Marine JD Series SD Series SR Series VDC Series Double Pair of Screws, Very High Pressure Design, External Timing Gears up to 600 m3/h 100 Bar Oil&Gas, Industrial Double Pair of Screws, Heavy Duty Design, Internal Timing Gears up to 1200 m3/h 25 Bar Oil&Gas, Industrial, Marine Double Pair of Screws, Light & Compact Design, Internal Timing Gears up to 1200 m3/h 14 Bar Oil&Gas, Industrial, Marine Double Pair of Screws, Heavy Duty Design, Vertical Submerged, Internal Timing Gears up to 1000 m3/h 50 Bar Oil&Gas, Marine 19
Capacity(m3/h) PERA-PRINZ TWIN SCREW PUMPS COVERAGE CHART 3500 Twin screw pump coverage chart 3000 2500 2000 1500 1000 500 0 0 10 20 30 40 50 60 70 Differential pressure(bar) 20
Pump type TWIN SCREW PUMPS EXTERNAL TIMING GEARS Pump Series HR Series: HRV Series Installation Options: Horizontal Vertical Executions: Optimized for Applications in: Suitable to Fluid having the following properties: Standard & API 676 with deviations - Timing Gears - External Gears and Bearings Pump Series HR Series: Maximum design pressure: 14 bar (standard) [204 psig] Flow rates: up to 3500 m3/h [15400 GPM] Viscosity of the pumped fluid: up to 35.000 cst Pipe Nominal Size DN: from 50 to 750 [from 2 up to 30 ] Rotation speed: from 200 up to 2200 rpm Temperature range: -46 / +300 C [-51 / +572 F] Pulsations: Minimized (almost zero) Bearing types: Petrochemical, Chemical, Shipbuilding, General Industry, Oil&Gas Abrasive and not Abrasive Corrosive (Alkaline / Acid / Aggressive) and not Corrosive Low / Medium / High / Very High Viscosities Not Lubricating or Lubricating Medium / High percentage of Gas or Air dissolved in Liquid Slightly Dirty (small soft particles) External Bearings and Gears in oil bath / grease 21
Pump type TWIN SCREW PUMPS - EXTERNAL TIMING GEARS Pump Series HD Series: HDL Series: HDV Series Installation Options: Horizontal (Cast Casing) Horizontal (Fabricated Steel Casing, with Replaceable Liner) Vertical Executions: Optimized for Applications in: Suitable to Fluid having the following properties: Standard & API 676 - Timing Gears - External Gears and Bearings Oil&Gas, Petrochemical, Chemical, Shipbuilding, General Industry Abrasive and not Abrasive Corrosive (Alkaline / Acid / Aggressive) and not Corrosive Low / Medium / High / Very High Viscosities Not Lubricating or Lubricating Medium / High percentage of Gas or Air dissolved in Liquid (Multiphase versions available) Slightly Dirty (small particles) Pump Series HD Series: Maximum design pressure: 20 bar (standard) [300 psig] Flow rates: up to 3500 m3/h [15400 psig] Viscosity of the pumped fluid: up to 35.000 cst Pipe Nominal Size DN: from 50 to 750 [from 2 up to 30 ] Rotation speed: from 200 up to 2200 rpm Temperature range: -46 / +350 C [-51 / +662 F] Pulsations: Minimized (almost zero) Bearing types: External Bearings and Gears in oil bath 22
Pera Prinz - Comparison between HR and HD Series 23
Pera Prinz - Some HD Series pumps dimensions 24
Pump Series Pump type Installation Options: Executions: Optimized for Applications in: Suitable to Fluid having the following properties: TWIN SCREW PUMPS - EXTERNAL TIMING GEARS UDL Series & UDV Series & UD Series: JDL Series JDV Series: Horizontal (Fabricated Steel Horizontal (Cast Casing, with Replaceable Casing) Liner) Vertical Standard & API 676 - Timing Gears - External Gears and Bearings Oil&Gas, Petrochemical, Chemical, Shipbuilding Abrasive and not Abrasive Corrosive (Alkaline / Acid / Aggressive) and not Corrosive Low / Medium / High / Very High Viscosities Not Lubricating or Lubricating Medium / High percentage of Gas or Air dissolved in Liquid (Multiphase versions available) Slightly Dirty (small particles) Pump Series UD Series: JD Series_ 149 barg [2170 psig] Maximum design pressure: 50 barg [730 psig] max ANSI 900 rating Flow rates: up to 1000 m3/h [4000 GPM] up to 600 m3/h [2650 GPM] Viscosity of the pumped fluid: up to 35.000 cst up to 35.000 cst Pipe Nominal Size DN: from 50 to 400 from 2 to 16 from 50 to 400 from 2 to 14 Rotation speed: from 200 up to 2200 rpm from 200 up to 2200 rpm Temperature range: -46 / +350 C [-51 / +662 F] -46 / +350 C [-51 / +662 F] Pulsations: Minimized (almost zero) Minimized (almost zero) Bearing types: External Bearings and Gears 3P Prinz oil Pump bath Manufacturing External Company Bearings and Gears in oil bath 25
Pump type SR Series: TWIN SCREW PUMPS - INTERNAL TIMING GEARS High Capacity Double End Twin Screw Pump Internal Gears and Bearings (Wetted and cooled by the Pumped Fluid); Maximum Pressure 14 barg [204 psig] ; Suitable only to Clean and Lubricating Fluids (no Abrasive Particles) SR-V Series: Vertical Installation Version of SR Series SD Series: High Capacity Double End Twin Screw Pump Internal Gears and Bearings (Wetted and cooled by the Pumped Fluid); Maximum Pressure 16 barg [232 psig] ; Higher Pressures Executions available on request; Suitable only to Clean and Lubricating Fluids (no Abrasive Particles) SD-V Series: Vertical Installation Version of SD Series 26
Pump type Pump Series Installation Options: Executions: Optimized for Applications in: Suitable to Fluid having the following properties: VERTICAL TWIN SCREW PUMPS - INTERNAL TIMING GEARS VDC Series: Vertical - Submerged Standard & API 676 - Timing Gears - External Gears and Bearings Oil&Gas, Petrochemical, Shipbuilding Abrasive and not Abrasive Corrosive (Alkaline / Acid / Aggressive) and not Corrosive Low / Medium / High / Very High Viscosities Not Lubricating or Lubricating Medium / High percentage of Gas or Air dissolved in Liquid (Multiphase versions available) Slightly Dirty (small particles) Pump Series VDC Series: Maximum design pressure: 50 barg [730 psig] Flow rates: up to 600 m3/h [2650 GPM] Viscosity of the pumped fluid: up to 35.000 cst Pipe Nominal Size DN: from 50 to 400 from 2 to 16 Rotation speed: from 200 up to 2200 rpm Temperature range: -46 / +350 C [-51 / +662 F] Pulsations: Minimized (almost zero) Bearing types: Bearings and Gears wetted by Pumped Fluid 27
Pump type SCREW PUMPS - TIMING EXTERNAL GEARS OVERHUNG SCREWS SINGLE VOLUTE Pump Series HM Series: HM-V Series: Installation Options: Horizontal Vertical Executions: Optimized for Applications in: Suitable to Fluid having the following properties: Standard & API 676 - Timing Gears - External Gears and Bearings Oil&Gas, Petrochemical, Chemical, Shipbuilding, Power Generation, General Industry Abrasive and not Abrasive Corrosive (Alkaline / Acid / Aggressive) and not Corrosive Low / Medium / High Viscosities Not Lubricating or Lubricating Medium percentage of Gas or Air dissolved in Liquid Slightly Dirty (small particles) Pump Series HM Series: Maximum design pressure: 20 bar (standard) Flow rates: up to 80 m 3 /h [353 GPM] Viscosity of the pumped fluid: up to 35.000 cst Pipe Nominal Size DN: from 40 to 100 [from 1.1/2 to 4 ] Rotation speed: from 200 up to 3600 rpm Temperature range: -46 / +300 C [-51 / +572 F] Pulsations: Minimized (almost zero) Bearing types: External Bearings and Gears in oil bath 28
PERA-PRINZ TWIN SCREW PUMPS HM250 29
PERA-PRINZ TWIN SCREW PUMPS HM200 VERTICAL (OFFSHORE / MARINE) 30
PERA-PRINZ TWIN SCREW PUMPS WITH ELECTRIC MOTOR HD PUMPS WITH DRAIN 31
PERA-PRINZ TWIN SCREW PUMPS WITH ELECTRIC MOTOR HD PUMPS WITHOUT DRAIN 32
PERA-PRINZ TWIN SCREW PUMPS WITH ELECTRIC MOTOR HM PUMPS 33
PERA-PRINZ TWIN SCREW PUMPS MODEL DE-CODIFICATION: HD, HR, UD, JD, SD, SR Series PUMP SERIES: HD, HR, UD, JD, SD, SR MATERIAL OF BODY LINER MATERIAL ACCESSORIES / OPTIONS HD 0 12 G2 C2 0 T01 NZ PUMP EXECUTION: 0 (no liner) L (with liner) V (vertical) PUMP SIZE MODEL: HD, UD, JD, SD: 06, 07, 10, 12, 14, 17, 20, 22, 25, 30 MATERIAL OF SCREWS + SHAFTS TYPE OF MECHANICAL SEAL: T01: component type T02: single, cartridge API 682 T03: double, cartridge API 682 T04: single cartridge, not API T0B: Packing type seal Others: please contact 3P Prinz HR, SR: 09, 14, 18, 23, 30, 37, 50 34
PERA-PRINZ TWIN SCREW PUMPS MODEL DE-CODIFICATION: HM Series PUMP SERIES: HM MATERIAL OF BODY ACCESSORIES / OPTIONS HM 050 G2 C2 T01 NZ Z PUMP SIZE MODEL: HM: 050, 100, 200, 250, 300 MATERIAL OF SCREWS + SHAFTS TYPE OF MECHANICAL SEAL: T01: component type T02: single, cartridge API 682 T03: double, cartridge API 682 T04: single cartridge, not API T0B: Packing type seal Others: please contact 3P Prinz PUMP EXECUTION: Z (no liner) V (vertical) 35
PERA-PRINZ TWIN SCREW PUMPS MAIN MATERIALS USED MATERIALS DESCRIPTION Cast Iron Ductile Cast Iron Carbon Steel (Casting) Carbon Steel (Fabricated) Carbon Steel (Barstock / Forging) Low Temperature Carbon Steel (Casting) MATERIAL INTERNATIONAL CODE GG25 (G25) GJS-400 (GGG400) ASTM A216 WCB ASTM A105 / ASTM A516 Gr.60 ASTM A105 ASTM A352 LCB Low Temp. Carbon Steel (Barstock/Forging) ASTM A350 LF2 Nickel-Aluminium Bronze ASTM B148 type Stainless Steel 12% (Cast) CA6NM Stainless Steel 12% (Barstock/Generic) AISI 420 Stainless Steel 316 grade (Cast) ASTM A351 CF8M (1.4408) Stainless Steel 316L grade (Cast) ASTM A351 CF3M (1.4404) Stainless Steel 316/316L grade (Barstock) ASTM A479 or A276 316 or 316L Stainless Steel 17-4PH grade (Barstock) ASTM A564 630 or commonly 17-4PH (1.4542) Stainless Steel 431 grade (Barstock) AISI 431 (1.4057) Duplex stainless steel 22% Cr (Cast) ASTM A890 Grade 4A or A995 Gr.4A (1.4462) Duplex stainless steel 22% Cr (Barstock) ASTM A479 F51 / UNS S31803 (1.4462) OTHER MATERIALS: PLEASE CONTACT 3P PRINZ 36
PERA-PRINZ TWIN SCREW PUMPS MAIN MATERIALS COMBINATIONS HD, UD, JD, SD Series REFINED HYDROCARBON PRODUCTS (not corrosive, low water content): GASOLINE, DIESEL, NAPHTA, MAZOUT, HEAVY FUEL OIL, LUBE OIL Casing Material Screws Material Shafts Material Stuffing Box Material GG25 GJS-400 or AISI 4140 AISI 4140 A105 / A516 Gr.60 GJS-400 GJS-400 or AISI 4140 AISI 4140 A105 / A516 Gr.60 BITUMEN, TAR (WITH HEATING JACKET) Casing Material Screws Material Shafts Material Stuffing Box Material Fabricated Carbon Steel + GG25 Liner AISI 4140 AISI 4140 A105 / A516 Gr.60 Fabricated Carbon Steel + GG25 Liner AISI 431 or AISI 420 17-4PH A105 / A516 Gr.60 SWEET CRUDE OIL Casing Material Screws Material Shafts Material Stuffing Box Material ASTM A216 WCB (GG25 or GJS-400 when allowed) AISI 4140 AISI 4140 A105 / A516 Gr.60 Fabricated Carbon Steel + GG25 Liner AISI 431 or AISI 420 17-4PH A105 / A516 Gr.60 37
PERA-PRINZ TWIN SCREW PUMPS MAIN MATERIALS COMBINATIONS HD, UD, JD, SD Series SOUR CRUDE OIL Casing Material Screws Material Shafts Material Stuffing Box Material ASTM A216 WCB, NACE MR-0175 AISI 420 or AISI 316 17-4PH A105 / A516 Gr.60 Fabricated Carbon Steel + A216 WCB Liner, NACE MR-0175 AISI 431 or Duplex 22% Cr 17-4PH A105 / A516 Gr.60 AISI 316/316L (Cast or Fabricated) Duplex 22% Cr Duplex 22% Cr AISI 316 / 316L Duplex 22% Cr (Cast) Duplex 22% Cr or Superduplex 25%Cr Duplex 22% Cr or Superduplex 25%Cr Duplex 22% Cr CHEMICALS Casing Material Screws Material Shafts Material Stuffing Box Material AISI 316/316L (Cast or Fabricated) AISI 316/316L or AISI 431 or 17-4PH 17-4PH AISI 316 / 316L Bearing Housing and Timing Gear Housing: Cast Iron or Fabricated Steel 38
PERA-PRINZ TWIN SCREW PUMPS MAIN MATERIALS COMBINATIONS HD, UD, JD, SD Series CHEMICALS Casing Material Screws Material Shafts Material Stuffing Box Material AISI 316/316L (Cast or Fabricated) AISI 316/316L or AISI 431 or 17-4PH 17-4PH AISI 316 / 316L HYDROCARBONS WITH SEAWATER CONTENT / SEAWATER (Example: Slops) Casing Material Screws Material Shafts Material Stuffing Box Material GG25 or GJS-400 Duplex 22% Cr 17-4PH A105 / A516 Gr.60 Nickel-Alum Bronze Duplex 22% Cr Duplex 22% Cr AISI 316 / 316L Super Duplex 25% Cr (Cast) Super Duplex 25%Cr Super Duplex 25%Cr Super Duplex 25% Cr Bearing Housing and Timing Gear Housing: Cast Iron or Fabricated Steel 39
PERA-PRINZ TWIN SCREW PUMPS MAIN MATERIALS COMBINATIONS HR, SR Series REFINED HYDROCARBON PRODUCTS (not corrosive, low water content): GASOLINE, DIESEL, NAPHTA, MAZOUT, HEAVY FUEL OIL, LUBE OIL Casing Material Screws Material Shafts Material Stuffing Box Material (including Bearing Housing and Timing Gear Housing) GG25 GJS-400 or AISI 4140 17-4PH A105 / A516 Gr.60 GJS-400 GJS-400 or AISI 4140 17-4PH A105 / A516 Gr.60 SWEET CRUDE OIL Casing Material Screws Material Shafts Material Stuffing Box Material (including Bearing Housing and Timing Gear Housing) GG25 AISI 4140 17-4PH A105 / A516 Gr.60 GJS-400 AISI 4140 17-4PH A105 / A516 Gr.60 HYDROCARBONS WITH SEAWATER CONTENT / SEAWATER (Example: Slops) Casing Material Screws Material Shafts Material Stuffing Box Material (including Bearing Housing and Timing Gear Housing) GG25 Duplex 22% Cr 17-4PH A105 / A516 Gr.60 GJS-400 Duplex 22% Cr 17-4PH A105 / A516 Gr.60 40
PERA-PRINZ TWIN SCREW PUMPS INFLUENCE OF VISCOSITY LOW VISCOSITY FLUIDS EFFECTS: - Backflow (Slippage) increases - Volumetric Efficiency decreases LOWER DIFFERENTIAL PRESSURE LIMITATION LOWER CAPACITY - Less friction losses / Higher Mechanical Efficiency - Speed should be increased up to 1450-1800 rpm (or even more) - It is not recommended to run the pump at low speeds with low viscosities (limited differential pressures and capacity) 41
PERA-PRINZ TWIN SCREW PUMPS INFLUENCE OF VISCOSITY HIGH VISCOSITY FLUIDS EFFECTS: - Backflow (Slippage) decreases - Volumetric Efficiency increases HIGHER DIFFERENTIAL PRESSURE POSSIBLE HIGHER CAPACITY - Higher friction losses / Lower Mechanical Efficiency - Speed should be decreased to low speed in order to fill up the chambers without formation of vacuum in the suction - It is not recommended to run the pump at high speeds with high viscosities (risk of malfunctioning of the pump because of vacuum in the suction) 42
PERA-PRINZ TWIN SCREW PUMPS INFLUENCE OF VISCOSITY FLUIDS BEHAVIOUR: - NEWTONIAN FLUIDS: Viscosity is not influenced by the shear force Viscosity remains constant when the fluid flows through the pump - NON-NEWTONIAN FLUIDS: Viscosity is influenced by the shear force (time dependent viscosity Viscosity drops if higher shear is applied when fluid flows through the pump FLUID TEXTURE MAY CHANGE AFTER SHEAR IS APPLIED 43
PERA-PRINZ TWIN SCREW PUMPS INFLUENCE OF VISCOSITY SHEAR SENSITIVE FLUIDS: - SOME NON-NEWTONIAN FLUIDS - EMULSIONS (water+oil, water+oil+air) TWIN SCREW PUMPS HANDLE THE FLUID WITH A LOW SHEAR : - The main part of the fluid is pumped with an axial movement (not centrifugal, not turbulent), without acceleration and with low shear - The small part of the fluid that back flows through the gaps between screws and liner is pumped with higher shear HIGH SHEAR / TURBULENCE CAUSES FOAM 44
CENTRIFUGAL PUMPS OR OTHER HIGH SHEAR PUMPS (example Gear Pumps) HIGH SHEAR / TURBULENCE CAUSES FOAM when oil/water emulsions are pumped; Light hydrocarbons may become gas when depressurized Foam decreases productivity and may cause downtimes Production Costs increase TWIN SCREW PUMPS AVOID THE FORMATION OF FOAM AND INCREASE PRODUCTIVITY 45
PERA-PRINZ TWIN SCREW PUMPS GAS HANDLING Twin Screw Pumps can handle a reasonable percentage of Gas dissolved in the liquid Depending on the application, they can handle up to 50% of Gas! An analysis of the application shall be executed in order to confirm suitability: - Type of application (Upstream or Downstream) - Availability of all the Process Parameters - How the Gas is mixed in the Fluid: Dissolved? Gas Bubbles? Gas Slugs? MULTIPHASE PUMPS 46
PERA-PRINZ TWIN SCREW PUMPS HANDLING SAND PARTICLES Twin Screw Pumps can handle a small quantity of sand dissolved in the liquid. It is important to know the Sand Particle Size Distribution. The Sand Particles will increase wear on the screws / liner. The pump performance may lower due to increased clearance that increases backflow. It is not possible to predict the wear out caused by sand particles, but some actions can be taken during offer and design stage: Examples: - Hardening of Screws and Liner (including Tungsten Carbide Overlay) - Replaceable Liners - Increased clearances between screw/screw and screws/liner 47
PERA-PRINZ TWIN SCREW PUMPS HANDLING SAND PARTICLES WORST CONDITIONS FOR PUMPING SAND PARTICLES: - Fluid Viscosity is Low - High Pump RPMs - Higher Differential Pressures - Percentages of Solid Particles higher than 0,01% in volume Pumping low viscosity liquid with sand particles at high speeds increases sensitively the abrasion effect PUMP PERFORMANCES MAY DECREASE QUICKLY Frequent maintenance and spare parts replacement It is important to select the right pump execution and materials 48
PERA-PRINZ TWIN SCREW PUMPS SELF PRIMING DRY RUNNING SELF PRIMING Twin Screw Pumps are Self Priming if the internal chamber is wet (slightly filled with fluid) Twin Screw Pumps (except FMH hygienic pumps, that are self-draining) are designed to retain some liquid inside the pumping chamber DRY RUNNING Twin Screw Pumps, thanks to the non-contacting screws, can run dry Standard mechanical seals will heat up quickly during dry running: - Select proper facing materials of the mechanical seals - For longer dry running periods, select quenching on double mechanical seals 49
PERA-PRINZ TWIN SCREW PUMPS SUCTION & NPSH Twin Screw Pumps have high suction lift and low NPSHr pumps. Generally, Centrifugal Pumps have worse suction lift. The Fluid enters the Pump Suction Flange and, because of frictions and hydraulic effects (changes of flow, turbulences etc.), the hydrostatic pressure of the fluid drops down. If the Fluid Pressure in a major cavity of the pump drops down the vapor pressure, then the liquid will vapourize (formation of vapor/gas bubbles in the liquid). 50
PERA-PRINZ TWIN SCREW PUMPS SUCTION & NPSH SUCTION LIFT PERFORMANCES DEPEND ON: - PUMP CONSTRUCTION: Geometry of the Chamber and Suction Port - PUMP SPEED: Higher Speed = Higher Vacuum on Suction = Higher NPSHr - PUMP CAPACITY: Higher Capacity on the same pump = Higher Hydraulic Losses = Higher NPSHr - FLUID VAPOUR PRESSURE: fluids with high vapour pressure need pumps with Lower NPSHr in order to avoid cavitation 51
PERA-PRINZ TWIN SCREW PUMPS SUCTION & NPSH CAVITATION If the Pressure in any part of the Pump Chamber falls below the Fluid Vapour Pressure, the Fluid will vapourize (formation of bubbles of gas/vapour inside the liquid). On other part inside or downstream of the pump, because of the pumping effect, the fluid pressure will be over the Vapour Pressure again, and the gas bubble will implode suddenly and become liquid again. This implosion is very fast and a multitude of collapsing bubbles generates a noise similar to «Cracking» «Small stones passing inside the piping» The implosions are so strong that they can damage the wetted metallic surfaces of the pumps and create a particular erosion effect. The effects of Cavitation may destroy a pump quickly Cavitation will directly decrese the Pump Performances 52
PERA-PRINZ TWIN SCREW PUMPS SUCTION & NPSH EFFECTS OF CAVITATION CENTRIFUGAL PUMPS 53
PERA-PRINZ TWIN SCREW PUMPS SUCTION & NPSH NPSHr = Net Positive Suction Head required This is the Minimum Head required by the pump, calculated at the Suction Flange, in order to avoid Cavitation at a certain Flow Rate and with a certain Fluid. NPSHa = Net Positive Suction Head available This is the difference between the Pressure at the Suction Flange of the Pump and the Fluid Vapour Pressure In order to avoid Cavitation, NPSHa must be higher than NPSHr: NPSHa > NPSHr 54
PERA-PRINZ TWIN SCREW PUMPS SUCTION & NPSH How to improve (=increase) NPSHa: Reduction of Friction Losses and Hydraulic Losses: - Larger Diameter Piping - Reduction of Piping Elbows - Smoother rugosity values of the Piping - Less Valves (or Full Bore Valves) - Reduction of the Velocity of the Fluid and avoidance of Turbulent Flow - Avoid changes of diameter of the Piping - Position of the Pump below the suction tank (example, in an underground Pit) 55
PERA-PRINZ TWIN SCREW PUMPS SUCTION & NPSH How to improve (= lower) NPSHr: - Select a pump with low NPSHr (for example, a Twin Screw Pump) - Select an optimal geometry of the Pump Suction - Run the pump at the optimal speed (=not too fast speeds) - Select a pump slightly oversized for the required flow rate Very good realistic values of NPSHr are around 1,5 meters 56
PERA-PRINZ TWIN SCREW PUMPS SUCTION & NPSH Typical Suction Head Curve: When the capacity loss is higher than 3%, then it is assumed that Cavitation has started Gas entrained in the liquid (bubbles) will be degassed: The Performance Loss is smoother than in the Cavitation effect 57
PERA-PRINZ TWIN SCREW PUMPS PUMP EXECUTIONS FOR HIGH TEMPERATURES - Cast Casing Pumps with Heating Jacket - Fabricated Steel Pumps with Welded Heating Jacket - Pumps with Electric Tracing Coils - Cooling of the Timing Gearbox and of the Bearing Housing may be required - It is recommended to use a longer shaft for better cooling on the ends 58
PERA-PRINZ TWIN SCREW PUMPS SHAFT DEFLECTION It is important to assure high stiffness / rigidity of the shaft costruction, in order to minimize the deflection - Short Width and Compact Pump - Short Distance between the Bearings - High Elastic Module Materials (high rigidity) - Less deflection means smaller clearance between screws and liner 59
PERA-PRINZ TWIN SCREW PUMPS SPEED VARIATION Twin Screw Pumps are often operated by motors at fixed speed. The usage of a Speed Variation Device (for example Variable Frequency Drive) can give some advantages like: - Change of Capacity - Possibility of pumping a wide range of viscosities - Soft / Smooth Start-Up and Cold Starts - Improvement of Suction Capability (for example during Stripping) 60
PERA-PRINZ TWIN SCREW PUMPS PUMP INSTRUMENTATION Twin Screw Pumps can be mounted, on request, with the following accessories: - Temperature Sensors / Transmitters on Pump Bearings and / or Casing - Pressure Sensors / Transmitters on Pump Suction and / or Discharge Ports - Vibration Sensors on Pump Supports - API PLAN Seal Panels - Valves and Piping - Bearing / Gear Boxes Cooling Systems (by water or by air/oil), with natural and forced re-circulation - Dry Running Protection (Oil Pot) - All Motor Options and Executions in accordance to major Suppliers 61
PERA-PRINZ TWIN SCREW PUMPS MARINE & SHIPBUILDING Twin Screw Pumps for Marine & Shipbuilding: - Horizontal Executions (example some Cargo Loading/Unloading, Slops) - Vertical Executions: More common because of space saving; different executions can be offered; Non Submerged Versions and Submerged Versions available The following Class Certification and Inspections are available 62
PERA-PRINZ TWIN SCREW PUMPS MARINE & SHIPBUILDING VERTICAL EXECUTIONS Submerged Vertical Twin Screw Pump with Double Cardanic Shaft Vertical Twin Screw Pump, not submerged Submerged Vertical Twin Screw Pump supported by mounting stool 63
PERA-PRINZ TWIN SCREW PUMPS MARINE & SHIPBUILDING PUMP WITH BULKHEAD: The pump is in an hazardous area The motor is in a safe area; 64
PERA-PRINZ TWIN SCREW PUMPS MARINE & SHIPBUILDING Applications for Twin Screw Pumps for MARINE AND SHIPBUILDING: - Cargo Pumps - Engine Room Pumps - Stripping and ballast water Pumps - Bitumen tanker Pump - Slops - Stripping of Tank ADVANTAGES: - Ideal for pumping low and high viscosity products and oil&water mixes 65
PERA-PRINZ TWIN SCREW PUMPS TANK STORAGE Applications for Twin Screw Pumps for TANK STORAGE: - Loading / Unloading with high or low capacity - Pumping high or low viscosity products - Pumping at high or low pressure - Pumping at high or low pressure - Circulation from Tank to Tank - Stripping of Tank ADVANTAGES: - Installation of 1 inlet pipe (reduced installation costs) - Easier operation and higher safety due to variable operation 66
PERA-PRINZ TWIN SCREW PUMPS MARINE & SHIPBUILDING 3 SCREW PUMPS UNDER DEVELOPMENT THREE SCREW PUMP CAPACITY RANGE DESIGN PRESSURE MARKET MT Series Universal Mid-Pressure Three Screw Pump 50 m3/h 25 Bar Oil&Gas, Industrial, Marine 67
PERA-PRINZ TWIN SCREW PUMPS CRITICAL APPLICATIONS PROBLEM Sand Particles Content SOLUTION Replaceable Liner, Hard Coatings Corrosive Elements ( Salt / H2S and Sulfides / Chlorides) NACE material, Duplex, Superduplex Gas Content Mech Seals + API PLAN or Multiphase Toxic Fluids Double Mech Seals + API PLAN 52, 53, 54 Wax, Paraffin Hydrocarbons, Aromatic Hydrocarbons High Temperatures (example Bitumen, Tar) Mech seals heating / cold start issues Proper Elastomer Material Heating Jacket, Longer Shaft, cooled gears 68
PERA-PRINZ TWIN SCREW PUMPS CRITICAL APPLICATIONS PROBLEM SOLUTION Dry Running Double Seals with Quench, Oil Pot with Sensor Low NPSHa Right pump selection, optimize speed High Discharge Pressure Increase Casing Design Pressure (UD, JD) High Differential Pressure Longer Shafts, Increase Gap with Liner Low Environment Temperature Low Temp Materials and Lubrication High Environment Temperature High Elevation (Altitude) Sunshades, Gearbox Cooling, Derated Motor Motor derating 69
PERA-PRINZ TWIN SCREW PUMPS CRITICAL APPLICATIONS PROBLEM API 676 requirements SOLUTION Separate Relief Valve, Special Materials, API 682 Seals, API Baseplate ATEX requirements (Zone 0? Zone 1? Zone 2?) ATEX motor, ATEX Pump Other Hazardous Area Requirements (UL/FM, CSA) Suitable Motor certification Multi Pump Skid Package Clarify the Operational Requirements and Scope of Supply (Piping, Valves, Sensors, Inverter, PLC) 70
PERA-PRINZ TWIN SCREW PUMPS PUMP TESTING Our Twin Screw Pumps are 100% tested. Minimum Testing Standards: - Casing Hydrostatic Test: 1.5 times the casing design pressure for 10 minutes - Performance Test at Rated Conditions or at Re-calculated Conditions with Test Fluid Viscosity Standard VDMA 24 284 - Functional Running Test (no load) for checking Accessories Functionality (when included) Other Testing Standards: On request, we can perform tests in accordance to the major Standards 71
PERA-PRINZ TWIN SCREW PUMPS PUMP TESTING VDMA 24 284 Standard Permissible deviations for the capacity According to the Standard VDMA 24284, the reading of the capacity value performed with the instrument may deviate from the contract value according to the following values: Q (l/h) 100 +20% / -10% 100 Q (l/h) 1000 ±10% Q (l/h)>1000 +10% / -5% 72
PERA-PRINZ TWIN SCREW PUMPS PUMP TESTING VDMA 24 284 Standard Permissible deviations for the power According to the Standard VDMA 24284, Table 5, Group 2, the reading of the power value performed with the instrument may deviate from the contract value according to the following values: P (kw) 5 +25% 5 P (kw) 10 +20% 10 P (kw) 50 +15% P (kw)>50 +10% 73
PERA-PRINZ TWIN SCREW PUMPS PUMP TESTING API 676 Standard - Permissible deviations for the Capacity: Tolerance at 100% speed : +3% / -0% - Permissible deviations for the Power: Tolerance at rated pressure + capacity: +4% - Permissible deviations for the NPSHr: Tolerance at rated capacity: +0% 74
PERA-PRINZ TWIN SCREW PUMPS API 676 STANDARD Our Twin Screw Pumps can comply with API 676 Standard (2nd and 3rd edition) on request Some of the most important design conditions requested by API 676: - Relief Valve shall be external (we generally supply it «loose») - Baseplate shall be provided with lifting lugs, earthing bosses, levelling screws; it shall be suitable for grouting, it shall extend below the drive train components and accessories, and drain pipe shall extend up to baseplate edge - Mechanical seals shall be API 682, with suitable API PLAN as applicable 75
PERA-PRINZ TWIN SCREW PUMPS API 676 STANDARD MAIN EXCEPTIONS / DEVIATIONS POSSIBLE FROM API 676 3RD ED. PARA 6.9.4 (Last Sentence) Depending on the interaxis lenght between the 2 axis, there may not be sufficient space to assemble 2 API 682 Cartridge Seals; API 676 accepts that Cartridge type seals should be used when not unpractical: NOTE: Space or design parameters for some pump types, sizes, or applications make the use of API 682/ISO 21049 seals impractical SO THIS IS AN ACCEPTABLE DEVIATION FOR SMALL SIZE PUMPS (HD06, HD07, HR09, HR14) 76
PERA-PRINZ TWIN SCREW PUMPS API 676 STANDARD MAIN EXCEPTIONS / DEVIATIONS POSSIBLE FROM API 676 3RD ED. PARA 6.8.1.9 Rotors for twin screw pumps shall be dynamically balanced to ISO 1940-1 Grade 2.5. We generally propose Grade 16 in order to avoid costly calibration or more expensive double profile screws. PARA 6.8.2.1 Timing Gears of the Twin Screw Pump will be designed as per ISO Standards, not as per AGMA Standard. 77
PERA-PRINZ TWIN SCREW PUMPS API 676 STANDARD MAIN EXCEPTIONS / DEVIATIONS POSSIBLE FROM API 676 3RD ED. PARA 6.1.1. Uniterrupted years of operation does not generally exceed 2 years (instead of the 3 years required) because of Mechanical Seals Service Life PARA 6.12.9 and 6.12.10 Pressure lubrication system for Timing Gear Box and Bearing Housing is not generally to API 614, unless explicitally required (because of the major price impact) 78
PERA-PRINZ TWIN SCREW PUMPS API 676 STANDARD MAIN EXCEPTIONS / DEVIATIONS POSSIBLE FROM API 676 3RD ED. PARA 6.13.2.1. API 676 requires that «Unless otherwise specified, the materials of construction of the pressurecontaining casing shall be carbon steel as a minimum». When technically possible, we propose as alternative Cast Iron Casing, unless Carbon Steel is specifically required on the Data Sheets. PARA 7.5.1 and 7.5.2 Pressure Limiting Valves (Relief Valves), in downstream applications, may be supplied not fully as per API 520 and 526 standards. 79
PERA-PRINZ TWIN SCREW PUMPS API 676 STANDARD MAIN EXCEPTIONS / DEVIATIONS POSSIBLE FROM API 676 3RD ED. PARA 8.2.2.1.1 Radiographies are not offered, in case Purchaser request for them. As alternative, we propose other NDE tests. PARA 8.3.6 Test Tolerances proposed are in accordance with VDMA 24 284 Table 5 group 2. 80
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