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to the application of diffusion coatings, or in advanced ion and plasma-type surfacing techniques. Vacuum pumps are used for drying, distillation, and evaporation. Lower boiling temperatures attained under vacuum preserve nutrients and improve taste, quality, and shelf life of products such as candies, jams, pharmaceuticals, and many mild products. Deaeration is needed for products such as meat pastes, sauces, soups, cellulose, latex, bricks, tiles, sewer pipes, and pottery clay. Also, vacuum conveyance of dangerous, viscous, contaminated, powdery, flaky, bulky, or simply hard-to-handle materials or products is used. The author remembers the ease and utter simplicity with which laminated plastic toothpaste tubes are transferred in partially Pumps P-311 FIG. P-320 Hydraulic range chart (Type VCR 8). (Source: Sulzer Pumps.) evacuated, transparent plastic pipes from the forming machine at one end of the plant to the filling equipment at the other end of the building. With a profusion of processes and applications thus benefiting from vacuum pumps, it is not surprising that many different types and styles, sizes and models, and configurations and variations of vacuum producing machinery are available to the user. The familiar steam, gas, and fluid jet injectors/eductors must be acknowledged as prime vacuum producers; however, we will only mention them in passing because they lack moving parts and thus do not fit our definition of “machinery.” Vacuum pumps are often classified in two broad categories: dry type and liquid type. Dry types include lobe, rotary piston, sliding vane, and even diaphragm P-312 Pumps FIG. P-321 Hydraulic range chart (Type VCR 8). (Source: Sulzer Pumps.) Pumps P-313 TABLE P-40 VCR8 Design Features, Advantages, and Benefits Features Advantages Benefits Driver Vertical motor with solid shaft Precision alignment Improved seal and bearing life stand assembly Integral thrust bearing Axial and radial setting of rotor Standard driver may be selected Controls hydraulic thrust Improved seal life Driver alignment Controls motor radial position Reduced maintenance time positioning screws Spacer coupling Allows seal and bearing Reduced maintenance time maintenance without disturbing driver Dimpled location Consistent vibration monitoring Trend for planned maintenance Head ANSI B16.5 class 300 flanges Consistent with process piping Use of standard pipe flanges assembly standards Nozzle load capability per Simplifies piping layout Reduces piping layout costs API 610 Complies with API 682, Allows use of API 682 single Improved seal life, reduced Table 1 or dual seals as required emissions Allows interchangeability Reduced inventory Throttle bushing assembly Controls seal chamber pressure Improved seal life Provides rotor stiffness Allows use of various API 610 Greater flexibility piping plans Column Flanged and bolted with Controls axial and radial Improved reliability assembly register fit position of bowl assembly Ease of maintenance Bearing bushing spacing per Ensures adequate separation Improved reliability API 610 margin from critical speeds Bowl Flanged and bolted with Controls axial and radial Improved reliability assembly register fit position of bowl assembly Ease of maintenance Low NPSH first-stage impeller Reduced pump setting length Reduced construction cost Between bearings first-stage Reduced deflection Improved reliability impeller design Impeller keyed to shaft Positive drive and positioning Improved reliability Impellers hydraulically thrust Reduced thrust load Improved bearing life balanced Single piece shaft Simplifies assembly Ease of maintenance construction £16 feet Controls runout Improved reliability Dynamically balanced Reduced unbalance Improved seal life enclosed-type impeller Improved reliability Replaceable wear surfaces Allows refurbishment to as- Reduced total life cycle cost new condition Suction 600psi pressure rating Consistent with process Improved plant reliability can piping design assembly Controlled fluid velocities Reduces internal losses Improved first-stage impeller Reliable suction performance life Internal or external drain Allows evacuation of process Reduces maintenance costs fluids Separate mounting plate Allows through bolting on Improved maintenance and discharge head reliability Soleplate optional Allows foundation to be Simplified construction process completed prior to pump installation Confined gasket Controlled compression ensures Reduced risk of leakage reliable pressure retention P-314 Pumps TABLE P-41 VCR8 Pumps Design Criteria Bowl Sizes Capacity Head (per Stage) Pressure Temperature Speed SI units 150 to 255 mm to 230 m 3 /h to 60 m to 70 bar to 205°C to 3600 rpm U.S. units 6 to 10 in to 1000 gpm to 200 ft to 1000 psi to 400°F to 3600 rpm TABLE P-42 VCR8 Pumps Design Criteria Bowl Sizes Capacity Head (per Stage) Pressure Temperature Speed SI units 300 to 450 mm to 475 m 3 /h to 60 m 70 bar to 205°C to 2960 rpm 12 in U.S. units 12 to 18 in to 2100 gpm to 200 ft 1000 psi to 400°F to 1800 rpm other sizes FIG. P-322 Pump external view (type CD 8). (Source: Sulzer Pumps.) TABLE P-43 CD8 Pumps Operating Data SI Units U.S. Units Discharge sizes 150 to 300 mm 6 to 12 in Capacities to 2750 m 3 /h to 17,000 gpm Heads to 400 m to 1400 ft Pressures to 50 bar to 735 psi Temperatures -28 to 425°C -20 to 800°F Speeds to 3100 rpm to 3800 rpm P-315 TABLE P-44 CD8 Features, Functions, and Benefits Features Functions Benefits Design Full-range coverage Selections fall within 80% to Smooth operation 110% of best efficiency point Longer service life Optimized efficiency Full compliance with API 610 Heavy duty design and Longer reliable service 8th edition requirements construction Suitable for 3 years uninterrupted service and 20 year service life Pressure Symmetrical, double end cover Improved maintenance access, All surfaces accessible casing construction cleanout and decontamination Completely drainable capabilities Reliable high-temperature operation Uniform warming Clockwise or counterclockwise Improved flexibility of application rotation with same component parts Cast construction with double Reduced radial loads Reduced rotor deflection volute and double suction Improved bearing and seal life entry Symmetry of flow into impeller Improved suction characteristics Centerline mounting with Suitable for operation in wide Reduced misalignment problems robust feet range of temperatures up to 800°F Reduced maintenance Integral end cover and Stiffer support eliminates Reduced frame vibration bearing hanger possible frame resonance Improved bearing and seal life Reduced number of component parts Simplified maintenance Available in various Suitable for operation in wide Optimized material selection to metallurgies, including S-4, range of services ensure appropriate service life S-6, C-6 and A-8 Seal chamber dimensions Suitable for state-of-the-art Improved seal interchangeability compliant with API 682 mechanical seal technology and seal life Table 1 Reduced emissions Impeller Double suction impeller Minimal axial loads Improved bearing life Low NPSHr Reduced vessel heights Improved NPSH margins 9000 to 11,000Nss suction Stable suction performance Reduced vibration hydraulics available throughout entire flow range Improved bearing and seal life 5 vane staggered construction Reduced hydraulic pulsations Reduced vibration available Improved bearing and seal life Simple and effective impeller Axially and radially secured in Secure in operation through retention all directions transient operating conditions Easily maintained Enclosed impeller Higher efficiencies Reduced power consumption No impeller setting Dynamic balance to 4W/N Minimized dynamic unbalance Reduced vibration forces Improved bearing and seal life Shaft Heavy duty shaft with Higher torque transmission Higher torsional stress safety minimum bearing span capability margin Lower static and dynamic deflection Improved reliability Stiff shaft design Ensures separation from critical Smoother operation at all speeds throughout entire allowable operating speeds operating range Taper shaft extension Simplified coupling, bearing and Reduced maintenance downtime seal maintenance Bearing All steel load bearing Reliable long-term service Maximized bearing reliability and components service life 40° angular contact thrust Selected for minimum 25,000 hours bearing L10 bearing life Deep groove radial bearing Heavy duty carrying capability INPRO TM labyrinth seals Minimized ingress of oil Improved bearing life fitted as standard contaminants Fan cooling or water cooling Efficient cooling features ensure options available cool running of bearings under all pump operating temperatures P-316 FIG. P-323 Design features (type CD 8). (Source: Sulzer Pumps.) Pumps P-317 FIG. P-324 Thrust bearing assembly (type CD 8 option). High capacity fan; water cooling; inboard heat dissipator; purge or pure mist oil lubrication. (Source: Sulzer Pumps.) FIG. P-325 Radial bearing assembly (type CD 8 option). Water cooling; inboard heat dissipator; purge or pure mist oil lubrication. (Source: Sulzer Pumps.) FIG. P-326 Impeller (type CD 8 option). Integral wear surfaces; nonmetallic wear rings. (Source: Sulzer Pumps.) P-318 Pumps FIG. P-327 Hydraulic range chart (type CD 8). (Source: Sulzer Pumps.) pumps. Liquid vacuum pumps include liquid jet and liquid ring pumps. Figure P- 335 shows the operating ranges for many of these pumps. It should be noted that there is considerable overlap among ranges. The most important vacuum producers and their respective operating modes and features are of interest to use in the order listed in Fig. P-335. Single-stage liquid ring pumps Figure P-336 depicts the operating principle of a liquid ring pump. Its circular pump body (A) contains a rotor that consists of a shaft and impeller (B). Shaft and impeller centerlines are positioned parallel, but eccentrically offset relative to the centerline of the pump body. The amount of eccentricity is related to the depth of the liquid ring (C). The liquid ring is formed by introducing service liquid, normally water, via the pump suction casing (L) and through the channel (D) positioned in the suction port plate (E). The centrifugal action of the rotating impeller forces the liquid toward the periphery of the pump body. By controlling the amount of service liquid within the pump body where the impeller blades are completely immersed to their root at one extreme (F) and all but their tips exposed at the other extreme (G), optimum pumping performance will be attained. Pumps P-319 FIG. P-328 Hydraulic range chart (type CD 8). (Source: Sulzer Pumps.) FIG. P-329 The use of rapid prototyping and computational fluid dynamics allows the optimization of pump performance. (Source: Sulzer Pumps.) [...]... (mN/m) 0.201/0 . 35 4/0 .58 4 2 23. 5/ 212.8/201.0 1 ,36 2.0/1 ,31 4.7/1,264 .3 8.96/ 15 .3/ 24.8 1.1 13/ 1.144/1.184 0.649/0.699/0.761 286.1/242.6/206 .3 10 .38 /11.01/11. 65 1 13. 6/1 05. 4/97 .3 8 .32 /9.02/9.79 15. 5/ 13. 2/11.0 1.6 83/ 2.649 /3. 969 2 93. 2/ 258 .6/2 15. 0 1, 054 .2/982.9/927.4 43. 9/71.2/114.6 2.1 13/ 2 .30 6/2.726 1.221/1 .51 9/2.160 156 .8/1 23. 8/ 95. 4 12.76/ 13. 83/ 14. 75 141 .3/ 1 23. 2/1 05 .3 14.8/17.7/22.8 9.6/6.4 /3. 5 This is the experimental... Deposits 15. 1 1.6 0.6 13. 3 36 .1 O Guideline Deposits Actual Deposits Regulated Deposits Esso, Novacor Actual Deposits Actual Deposits Average Authorized Deposits Average Actual Deposits 0.80 0.01 0.06 1.8 7.6 Guideline Deposits M Suncor Sarnia R-7 15 .3 1 .5 0 .5 12.7 36 .6 1.2 0.01 0.02 0.94 7.2 8.6 0.9 0 .3 10 .3 20 .5 0. 83 0.00 0.02 0.06 1.7 0.08 0.00 0.09 0.84 1 .3 14 .3 1.4 0 .5 12.9 34 .3 0.90 0.01 0. 03 0.66... products Approximate relative price Molar mass Refrigeration capacity at 0°C (kJ/m3) No 1,000 50 ,000 4.0/0.2 No — Yes 1 120.9 2,740 No 1,000 — 4.2/0. 15 No — Yes 1 86 .5 4 ,34 4 No 1,000 — — No — Yes 3 5 102.0 2,860 Yes 25 500 — Yes 15. 5/27 No 0/2 17.0 4 ,36 0 Yes 1,000 20,000 0.44/0.008 Yes 2.2/9 .5 No 0.1 44.1 3, 870 Yes 5, 000 50 ,000 5. 5/0.1 No — No 0.1 44.0 22,600 TLV: Threshold limit value (the refrigeration... temperature glide for the pair is very small, even though they may not form an azeotrope A 50 /50 mixture of R -32 and R- 134 a, for example, forms a zeotropic blend with a temperature glide of about 5 C at about 950 kPa A 50 /50 blend of R-1 15 and R-22 will form a perfect azeotrope, while a 50 /50 blend of R -32 and R-1 25 will form a near-azeotrope with a temperature glide of about 0.1°C The higher temperature... (type CP) (Source: Sulzer Pumps.) FIG P -33 4 Pump performance range (type CP) (Source: Sulzer Pumps.) Pumps P -32 3 FIG P -33 5 Typical pressure ranges for various vacuum pumping devices (Source: Stokes Division of Pennwalt Corporation, Philadelphia, Pa.) FIG P -33 6 Operating principle of liquid vacuum pumps (Source: SIHI Pumps, Inc., Grand Island, N.Y.) P -32 4 Pumps FIG P -33 7 Liquid ring vacuum pumping system... 0 0 100 0 0 100 0 0 5 100 100 0 0 0 0 0 0 0 0 0 0 7.2 8.8 Existing 6.7 + Expanded 2.1 12 1,1 63 0 0 0 0 0 11 .5 9.0 Existing 6.9 + Expanded 2.1 12 1,1 63 Aerobic bacteria Air blowing Altered refinery 0 0 0 0 0 13. 3 12 .5 New 12 1,160 7.1 7.9 New 12 1,1 45 99.9 0 0 0 0 0 71.9 74 .3 Existing 49.7 + Expanded 4.2 + New 20.4 8,114 Bacteria that require free oxygen to metabolize nutrients The process used to produce... 1 20.0 99.9 0 0 0 0 0 M, Monthly Amount; O, One-day Amount; D, Maximum Daily Amount Actual crude rate (1000 m3/day) Reference crude rate (1000 m3/day) Status Number of months in operation Number of tests reported 16 .3 19.1 Existing 12 1,1 63 6.1 5. 7 Existing 12 1, 157 10.4 11 .3 Existing 12 1,1 63 Glossary: Common Terms in the Refining Industry Activated carbon Actual deposits Adsorption Carbon that is specially...P -32 0 Pumps FIG P -33 0 Model testing, the next step, is necessary in the development process to validate numerical calculation done during computational fluid dynamics (CFD) calculations (Source: Sulzer Pumps.) FIG P -33 1 Once successful model testing has been achieved, 3D computer-aided design (CAD) and computer-aided manufacturing (CAM)... guidelines and regulated deposits are for monthly averages.) Yearly average of daily deposits (kg/1000 m3 of crude oil) Guideline Deposits Esso Sarnia, P.C Miss., Shell Actual Deposits Actual Deposits Actual Deposits 17.1 1.7 0.6 14 .3 41.1 0.22 0.02 0.02 0.70 11 .3 4.1 0.01 0. 05 0.86 20 .5 0 .50 0.01 0.00 0. 03 9.7 Oil and Grease Phenols Sulfide Ammonia nitrogen Total suspended matter B COMPLIANCE ASSESSMENT... in Fig P -33 8 A centrifugal pump circulates water (the usual hurling liquid) through the multijet nozzle and venturi and returns it to the separation chamber The water, forced at high velocity across the gap between the nozzle and venturi, entrains the air and gases in multiple jet streams, creating a smooth, steady vacuum in the air suction line and vacuum system This P -32 2 Pumps FIG P -33 3 Pump section . vacuum system. This P -32 2 Pumps FIG. P -33 3 Pump section (type CP). (Source: Sulzer Pumps.) FIG. P -33 4 Pump performance range (type CP). (Source: Sulzer Pumps.) Pumps P -32 3 FIG. P -33 5 Typical pressure. Pumps.) TABLE P- 43 CD8 Pumps Operating Data SI Units U.S. Units Discharge sizes 150 to 30 0 mm 6 to 12 in Capacities to 2 750 m 3 /h to 17,000 gpm Heads to 400 m to 1400 ft Pressures to 50 bar to 7 35 psi Temperatures. Temperature Speed SI units 150 to 255 mm to 230 m 3 /h to 60 m to 70 bar to 2 05 C to 36 00 rpm U.S. units 6 to 10 in to 1000 gpm to 200 ft to 1000 psi to 400°F to 36 00 rpm TABLE P-42 VCR8 Pumps Design