Accumulators

Until about 1932, all power systems for hydraulic presses were operated with water. With the advent of reliable, fast, high-pressure oil pumps, a trend of significantly less expensive oil pumps developed. Installations requiring a relatively uniform and constant supply of hydraulic power are preferably designed with drives drawing the pressurized liquid directly from the pumps. In installations with high power (and liquid) peak demands of short duration, it is in most cases advantageous to...

Sewage Systems

In most instances, sewage systems are divided into two parts collection systems and treatment systems. FIGURE 1 Factory-built conventional lift station (Smith & Loveless, Inc.) FIGURE 1 Factory-built conventional lift station (Smith & Loveless, Inc.) Collection Collection systems consist of a network of sewers that collect and convey sewage from individual residences, commercial establishments, and industrial plants to one or more points of disposal. Pumping stations are often needed at...

Head Losses In System Components

Pressure Pipes Resistance to flow through a pipe is caused by viscous shear stresses in the liquid and by turbulence at the pipe walls. Laminar flow occurs in a pipe when the average velocity is relatively low and the energy head is lost mainly as a result of viscosity. In laminar flow, liquid particles have no motion next to the pipe walls and flow occurs as a result of the movement of particles in parallel lines with velocity increasing toward the center. The movement of concentric cylinders...

Types Of Corrosion

General Corrosion General corrosion is corrosion that proceeds without an appreciable localization of attack. This type of corrosion occurs on metals or alloys that do not develop an effective passive film on the surface. Usually, the corrosion mechanism is oxidation with the formation of metal oxide corrosion products. General corrosion is most often encountered in pumps with carbon steels and copper base alloys. Cast irons also experience a specialized form of general corrosion, known as...

Z

Where H energy (total head) of system, ft lb lb or ft (N m N or m) V velocity, ft s (m s) g acceleration of gravity, 32.17 ft s2 (9.807 m s2) p pressure, lb ft2 (N m2) g specific weight (force) of liquid, lb ft3 (N m3) Z elevation above (+) or below (-) datum plane, ft (m) The velocity and pressure at the point of energy measurement are expressed in units of equivalent head and are added to the distance Z that this point is above or below the selected datum plane. If pressure is measured as...

Operating Characteristics

The operating characteristics covered in this section assume the fluid is a true incompressible liquid with a viscosity independent of the rate of shear (shear strain). Common fluids used in testing are either a light lubricating oil or cool water with small amounts of soluble oil added for lubricity. Displacement The theoretical or geometric displacement Qd of a rotary pump is the total gross fluid volume transferred from the OTI volume to the OTO per unit time. A standard unit of displacement...

2

*Test parameters ambient temperature, 1750 rpm, 2-3 ft s (0.6-0.9 m s). Corrosion fatigue strength (CFS) given at 100,000,000 cycles. All values are in ksi 1 ksi 6.894759 mPa. (UTS is ultimate tensile strength of material in air.) *Test parameters ambient temperature, 1750 rpm, 2-3 ft s (0.6-0.9 m s). Corrosion fatigue strength (CFS) given at 100,000,000 cycles. All values are in ksi 1 ksi 6.894759 mPa. (UTS is ultimate tensile strength of material in air.) increasingly damage the material, the...

Variants In Pumping Systems

For a fixed set of conditions in a pumping system, there is just one total head for each flow rate. Consequently, a centrifugal pump operating at a constant speed can deliver just one flow. In practice, however, conditions in a system vary as a result of either controllable or uncontrollable changes. Changes in the valve opening in the pump discharge or bypass line, changes in the suction or discharge liquid level, changes in the pressures at these levels, the aging of pipes, changes in the...

Pump Construction

The pump section views in Figures 5 to 8 illustrate the construction of some composite pumps. Components Figure 9 shows various pump components made from both thermoplastic and thermoset polymers. The enclosed impellers are made of thermoplastic resins FIGURE 5 ANSI ASME B73.5M pump (Flowserve Corporation) FIGURE 5 ANSI ASME B73.5M pump (Flowserve Corporation) because the front and back shroud can be ultrasonic- or vibration-welded together. Semi-open impellers can be made of either type of...

Motor Insulation

Insulation systems must be used in a motor to electrically insulate the windings from the mechanical parts of the motor as well as to insulate the phase winding conductors from one another. Extra insulation is also required between any adjacent phase windings for 230 or higher voltage motors. In general, the higher the operating voltage, the better the insulation system must be. All NEMA-designed electric motors are manufactured with cord laced end turns to assure that they are positioned so...

Pump Selection

A pump selection study should always be made, and its importance cannot be emphasized enough. Such studies permit selection of the type of pump and discharge system best suited to the project and provide the information needed to proceed with the design of the installation. In many cases, the type of pump required will be obvious. If more than one kind of pump would be satisfactory, the specifications should permit the pump manufacturer to make the choice. This is particularly advantageous when...

Pi Ah Q

V _ ps x Ah, x qTq l _ x hHY x Vv (8) Mechanical f _ _ ps P. Efficiency f Vm _ PS _ PS Efficiency f Vhy _ AH, _ AH, (10) Approximate formulas for the three component efficiencies of Eq. 8 will be given further on. Their product yields the overall pump efficiency as defined in Eq. 5, and reflects the following division of the pump losses a. External drags on the rotating element due to i) bearings, ii) seals, and iii) fluid friction on the outside surfaces of the impeller shrouds called disk...

Types Of Turbines

Three types of turbines will be discussed propeller (fixed and adjustable blades), Francis, and impulse. Figures 4 to 7 are illustrations of these turbine runners. Figure 8 shows a complete Francis turbine unit. The fixed- and adjustable-blade propellers and runners are essentially the same, with the exception that the adjustable is suited to a much wider range of loading conditions. This versatility is reflected in a higher manufacturing cost for the adjustable blade. The Francis runner is...

Wp minW2

Dp 1 -W Ds 1 (59a and b) where the 0.6 limit applies individually to Dp and Ds or to the sum of the two, in which case the limit is 1.2. Eqs. 59a and 59b, therefore, constitute a more useful form of the diffusion factor concept for assessing the blade loading and the choice of the number of blades in centrifugal pump impellers24. Finally, the total blade length or number of blades, should not exceed that necessary to limit the diffusion as just described, as this adds unnecessary skin friction...

Load Parameter W

FIGURE 16 Performance characteristics for tilting-pad hearings. equal to 1.0 will be, as expected, greater than for the LID equal to 0.5. If the reader uses the data as presented, the dimensional information will prove consistent. To make comparisons among the bearings, using the nondimensional data is not strictly proper because there may be slight inconsistencies in preloads, the bearings will not be operating at the same average viscosity, and so on. Subsequently, dimensional data derived...

William J Sembler

Pumps used in marine shipboard applications, both commercial marine and Navy, can typically be divided into several groups. These groups include pumps associated with a vessel's propulsion, pumps used with the generators that produce electricity, pumps used in ship's service systems, pumps used to provide hotel services for crew and passengers, and pumps that are used in cargo or other specialized systems. Because marine pumps must operate on a moving platform, they should be designed to...

Diagnosis from Visual Examination of Damage

BEARING DAMAGE Static thrust in excess of the bearing rating will cause cracking of the balls or rollers and of the race in rolling element bearings and metal scorings of the shoes in tilting-pad bearings. Bearing failure from dynamic loading in excess of the bearing rating will cause fatigue failures of the balls or rollers and race in rolling element bearings. It is important to differentiate clearly between static load failure and fatigue failure. This can be done by examination of a cross...

Model Similitude

The principle of dynamically similar fluid motion forms the basis for the design and operation of hydraulic models and the interpretation of experimental data. The basic concept of dynamic similarity is that two systems with geometrically similar boundaries have similar flow patterns at corresponding instants of time.11,12 To achieve this, all individual forces acting on corresponding fluid elements must have the same ratios in the two geometrically similar systems. The condition required for...

Fred R Szenasi Cecil R Sparks J Cwachel

The major concern regarding pump noise falls into two categories 1. Noise levels that do not meet applicable environmental criteria. Examples range from personnel noise exposure criteria to overside noise criteria for submarines. 2. Noise signatures that can be used to diagnose faulty pump operation or incipient failure. The proliferation of industrial noise regulations in recent years has taken much of the guesswork out of allowable noise levels insofar as personnel and community exposure is...

Sealing Requirements In The Petroleum Refining Industry

The API Standard 682 is an industrial standard developed by users with input from equipment and seal manufacturers. The goal of the standard was to create a specification for seals that would have a good probability of meeting emission standards defined by the U.S. Clean Air Act of 1990 and have a life of at least three years. The implementation of this specification indicates not only an increase in emissions control, but also a major increase in equipment reliability. The following...

Gas Turbine Support Systems

Starting Systems A form of mechanical cranking is necessary to bring a gas turbine up to its self-sustaining speed. The amount of energy necessary will depend on each manufacturer's design. Available systems include electric motors, diesel engines, and gasexpander turbines. Lubrication The gas turbine manufacturer normally provides a combined pumpturbine lubrication oil system. A main lubrication oil pump of sufficient capacity for the combined system is necessary, in addition to a standby pump...

Design And Functional Requirements

The preceding sections provided the procedures for determining the seismic response of pumping equipment. However, in order to determine the acceptability of these results, they have to be combined with the pump's normal operational loads and compared to predetermined stress limitations. In accordance with the ASME code, the customer's design specification shall advise the applicable load combinations and allowable stress values. Typically, the pump load combinations can be divided into four...

Casings And Diffusers

The Volute Casing Pump This pump (refer to Figure 1) derives its name from the spiral-shaped casing surrounding the impeller. This casing section collects the liquid discharged by the impeller and converts velocity energy to pressure energy. A centrifugal pump volute increases in area from its initial point until it encompasses the full 360 around the impeller and then flares out to the final discharge opening. The FIGURE 3 Horizontal single-stage double-suction volute pump (the numbers refer...

Chemical Resistance Of Composites

Composites do not corrode because they are non-conductive. Therefore, an electrochemical reaction does not take place. (An exception to this may be when electrically conductive long carbon fibers are used in the wrapping of a pressure vessel or a pump housing.) Their lack of resistance to different chemical fluids can degrade composite materials. This degrading can be in the resin, the reinforcing fiber, or in the coupling agent between the resin and fiber. If a composite material is going to...

Systemhead Curves

A pumping system may consist of piping, valves, fittings, open channels, vessels, nozzles, weirs, meters, process equipment, and other liquid-handling conduits through which flow is required for various reasons. When a particular system is being analyzed for the pur- FIGURE 9 Energy and hydraulic gradients FIGURE 9 Energy and hydraulic gradients pose of selecting a pump or pumps, the resistance to flow of the liquid through these various components must be calculated. It will be explained in...

Pressure

FIGURE 11 Arrangement for warm-up through pump casing drain connection FIGURE 12 Arrangement for warm-up through jumper line around discharge check valve FIGURE 12 Arrangement for warm-up through jumper line around discharge check valve short duration, a relief valve with an external return connection must be used and the liquid from the relief valve must be piped back to the source of supply. Surge Chambers Generally, centrifugal pumps do not require surge chambers in their suction or...

Liquid End Construction

Steam pumps are equipped with many types of liquid ends, each being designed for a particular service condition. However, they can all be classified into two basic types, the piston, or inside-packed, type and the plunger, or outside-packed, type. The piston pump (Figure 7) is generally used for low and moderate pressures. Because the piston packing is located internally, the operator cannot see the leakage past it or make adjustments that could make the difference between good operation and...

Altitude Climb Performance

The altitude climb performance required of an airframe boost pump is specified in terms of altitude achieved versus time in minutes, flow required with respect to altitude, the fuel tank temperature with respect to altitude, and the minimum pump pressure rise required versus altitude. The temperature versus altitude represents the cooling of the fuel through heat transfer to the cold ambient atmosphere and boiling of the fuel that is experienced in a climb event. Immediately upon take-off, as...

Info

FIGURE 8 Friction loss curves for mechanical pulp (C2 > C1). (Courtesy ITT Goulds Pumps, Inc.) FIGURE 7 Friction loss curves for chemical pulp (C2 > Ci). (Courtesy ITT Goulds Pumps, Inc.) FIGURE 8 Friction loss curves for mechanical pulp (C2 > C1). (Courtesy ITT Goulds Pumps, Inc.) The following analytical method for determining pipe friction loss is based on the recently published TAPPI Technical Information Sheet (TIS) 408-4 (Reference 1), and is applicable to stock consistencies...

Condenser Circulating Pumps

Types of Pumps Condenser circulating pumps may be of either horizontal or vertical construction. For many years, the low-speed, horizontal, double-suction volute centifugal pump (Figure 39) was the preferred type. This pump has a simple but rugged design that allows ready access to the interior for examination and rapid dismantling if repairs are required. The larger central station and combined cycle power plants have switched to wet-pit vertical pumps that are either fully or partially...

Turndown

Standard catalog hydrokinetic and hydroviscous units offer the regulation described above over a 5-to-1 turndown on centrifugal machines and 4-to-1 turndown when driving positive displacement pumps on constant-pressure systems. Specially designed fluid drives have been sold that give stable control at 10-to-1 turndown. Hydrodynamic units are limited primarily by heat dissipation capabilities and range from turndown values of 100 to 1 to 1.2 to 1. Figure 10 is typical of a boiler-feed pump where...

Vertical Pumps

Vertical-shaft pumps fall into two classifications dry-pit and wet-pit. Dry-pit pumps are surrounded by air, and the wet-pit types are either fully or partially submerged in the liquid handled. Vertical Dry-Pit Pumps Dry-pit pumps with external bearings include most small, medium, and large vertical sewage pumps, most medium and large drainage and irrigation pumps for medium and high heads, many large condenser circulating and water supply pumps, and many marine pumps. Sometimes the vertical...

X

FIGURE 4c Non-clog submersible sewage pump (Flowserve Corporation) FIGURE 4c Non-clog submersible sewage pump (Flowserve Corporation) Although non-clog pumps 8 in (203 mm) and small are available with self-priming (Section 2.4), most conventional sewage pumps are located so the impeller is always below water level in the suction wet well. This eliminates the need for specialized priming systems. Self-priming pumps have been used successfully to pump raw unscreened sewage, particularly in the...

Hsv

Has proven to be useful especially for high-specific speed pumps and turbines. The loading on the blades of a variable-pitch propeller, and therefore the minimum suction-side static pressure, is directly connected to the head developed. As this head increases with increasing blade setting angle, the loading increases, the minimum pressure drops, and the NPSHR goes up. Hence an identifiable limiting value of s is found to exist for such a machine. s-limits are presented for a range of specific...

The Liquidjet Liquid Ljl Pump

Equations for the LJL pump are much simpler than the corresponding LJGL and LJG equations because of the elimination of all f terms. In this case, Eqs. (1), (3), (5), and (7) reduce to the following set Pt - Po Z32b + 2SM2b2 (1 - b) - b2(2 + Kth)(1 + SM)(1 + M) (12) Pd - Pt Zb( 1 + SM)(1 + M)(1 - Kdl - a2) (13) Throat Entry Ps - Po ZS( 1 + Ken)M2 c2 Throat Diffuser Pump efficiency h is defined as the ratio of useful work rate on the secondary fluid Q2 to the energy extracted from the primary...

3

(2) Vital service pumps are generally unspared, partially spared, or multistage. When a vital machine is down, production loss or violation of environmental permits results. (3) Essential service pumps are required for operation and have an installed spare. A production loss will occur only if main and spare fail simultaneously. (4) Cartridge type mechanical seals shall include sleeve and gland. (5) Cartridge consists of assembled element plus discharge head, seal(s), and bearing housing(s)....

Hotel Service Pumps

FLASH-DISTILLING-PLANT pumps Many steam ships have multistage flash distilling plants that are used to generate freshwater from seawater. Several electric-motor-driven singlestage centrifugal pumps are used with a typical flash unit. Smaller pumps are often provided in a close-coupled configuration. A distiller-feed pump takes suction from a sea chest and supplies seawater to the distilling plant's first-stage flash chamber. This water often passes through various heat exchangers, such as a...

Pump Bid Requisition

It is obviously necessary to fully define the scope of supply for the desired piece of equipment. To do so requires the right amount of documentation provided by the purchaser (no more, no less) to match the type of equipment being purchased. This is easier said than done, but the engineer needs to be conscious of the fact that a bid requisition package should be clear and concise as possible. One industry joke relates the cost of a piece of equipment to the weight of the paper included in the...

10

The shut-off power is 34 hp (25 kW), arising from a power coefficient of 0.047 from Mockridge's correlation36 for a b2 D2 of 1.59 12 ( 40.4 304.8) 0.1325 as found from Figure 23. This is 44 of the design-point power, a typical result. As seen in Section 2.3.1, this percentage increases with specific speed, where, of course, b2 D2 is also larger36. The NPSHR ( NPSH3 for this example) at off-design conditions is estimated empirically. At the higher, non-recirculating flow rates, NPSHR is related...

883

All tabulated values are in units of (ft3 s) d5 2 d diameter, ft Dcrit critical depth, ft. For SI units, multiply (m3 h) m5 2 by 5.03 X 10-4 to obtain (ft3 s) ft5 2. Examples 2, 3, and 4 illustrate the use of this table. FIGURE 29 Area versus depth for a circular pipe pVD In SI units R -(p in kg m3, V in m s, D in m, m in N-s m2) FIGURE 29 Area versus depth for a circular pipe pVD In SI units R -(p in kg m3, V in m s, D in m, m in N-s m2) 1 meter 3.28 feet 1 VD (Vin m s, D in m) 129.2 VD (Vin...

Application To Pumps

Gas turbines are available to drive centrifugal pumps in a wide range of speeds and sizes, from 40 bp (30 kW) to over 20,000 hp (15,000 kW). It is not practical to list here all the avail able units because they are too numerous and are continually being upgraded and added to. A listing can be found in Sawyer's Gas Turbine Catalog, which is published annually. Pipeline Service Crude oil pipeline service has seen a tremendous growth in the use of gas turbine drivers since the mid-l950s, and this...

Special Applications

Systems for Sewage Pumps A pump handling sewage or similar liquids containing stringy material can be equipped with automatic priming, but special precautions must be used to prevent carry-over of the liquid into the vacuum-producing device. One approach is to use a tee on the suction line immediately adjacent to the pump suction nozzle, with a vertical riser mounted on the top outlet of the tee. This riser is blanked at the top, thus forming a small tank. The top of the tank is vented to a...

Hot Water Circulating

A centrifugal pump best meets the requirements of this service. Water is usually used in a closed circuit so that there is no static head. The only resistance to flow is that from friction in the piping and fittings, the heater, the heating coils or radiators, and the control valves. In selecting the pump, the total flow resistance at the required flow rate should be calculated as accurately as possible, with some thought as to how much variation there might be as a result of inaccuracy of...

Chaplis William K Bs Me Mba Section 31 Power Pump Theory

Section 3.2 Power Pump Design and Construction Product Engineering Manager, Flowserve Corporation, Phillipsburg, NJ Clopton, D. E., B.S. (C.E.), P.E. Section 9.1 Water Supply Assistant Project Manager, Water Quality Division, URS Forrest and Cotton, Inc., Consulting Engineers, Dallas, TX Cooper, Paul, B.S. (M.E.). M.S. (M.E.), Ph.D. (Engrg.), P.E. Chapter 1 Introduction Classification and Selection of Pumps Section 2.1 Centrifugal Pump Theory Section 2.2.6 Centrifugal Pump Magnetic Bearings...

048

208 gpm at 60 lb in2 gage 47.3 m3 h at 4.1 bar gage 208 + 100 308 gpm 47.3 + 22.7 70.0 m3 h The size is obtained from Figure 4. Enter Figure 4b at Q2 308 gpm (70 m3 h) and discharge head (H2 H3) 23.1 ( 20) 43.1 ft 7 ( 6.1) 13.1 m read eductor size of 4 in (102 mm) based on the discharge connection. NOTE If there were any appreciable length of run on the discharge line, it would be necessary to calculate the pressure drop in this line and recalculate the eductor size after adding the line loss...

Classification Of Seals By Design

Nonpusher Type Mechanical Seal

There are four seal classification groups Rotating or stationary seal head Single-spring or multiple-spring construction Pusher or nonpusher secondary seal design The selection of an unbalanced or balanced seal is determined by the pressure in the seal chamber. Balance is a way of controlling the contact pressure between the seal faces and power generated by the seal. When the percentage of balance b (the ratio of hydraulic closing area to seal face area) is 100 percent or greater, the seal is...

11

FIGURE 2 Single stage overhung refinery process pump API 610 Type OH2. (1) Pump casing, (2) Discharge flange flanges are standard ANSI B16.5 Class 300, (3) Metal-to-metal casing joint with fully confined, controlled compression gasket, (4) Casing drain at bottom of volute (not shown), (5) Suction nozzle guide vane (featured on some models, (6) Renewable casing and impeller wear rings, (7) Seal chamber with minimum standard dimensions, (8) Cartridge mechanical seal, (9) Impeller dynamically...

Discharge

FIGURE 5 Self-cleaning filter assembly FIGURE 5 Self-cleaning filter assembly is used for lubrication of the bearings and cooling of the motor. This fluid remains in the motor section and is circulated through the rotor cavity by an auxiliary impeller, which is an integral part of the rotor assembly. The fluid in the motor section is forced across the rotor and through the bearings, after which it flows through a heat exchanger. The heat exchanger is cooled by water or a suitable heat transfer...

Robert D Ashton Timothy Lwotring

Injection-type shaft seals (sometimes called packless stuffing boxes) are designed to control leakage from hot-water pumps. Cool water is injected into each seal to either suppress or regulate the hot leakage, which would otherwise flash upon reaching the outside of the pump. Injection-type shaft seals provide high reliability and yet require little maintenance. They are used primarily in power plant boiler-feed and reactor-feed pump applications where shaft peripheral speeds are high (3600 rpm...

M

Drive pumps, 2.303 magnetic bearings, 2.277-2.278 active, 2.282 backup systems, 2.279 catcher bearings, 2.279, 2.284 designing, 2.285 diagnostics, 2.291 feedback systems, 2.278-2.279 heteropolar, 2.285-2.288 homopolar, 2.289-2.290 imbalance loads, 2.282 installing, 2.291 pump operation, 2.292 reduced power consumption, 2.281 reliability, 2.281 rotors clearances, 2.282 dynamics, 2.281-2.283 stators, sizing, 2.284 transfer function, 2.283 transient loads, 2.283 tuning, 2.291 unit load...

McGrawhill

New York San Francisco Washington, D.C. Auckland Bogot Caracas Lisbon London Madrid Mexico City Milan Montreal New Delhi San Juan Singapore Sydney Tokyo Toronto In memory of our good friends and colleagues William C. Krutzsch Warren H. Fraser Igor J. Karassik A Division of The McGraw Hill Companies Copyright 2001, 1986, 1976 by The McGraw-Hill Companies, Inc. All rights reserved. Printed in the United States of America. Except as permitted under the United States Copyright Act of 1976, no part...

Types Of Gears

Types Gear Drive

The gears generally used for pump applications are parallel-shaft helical or herringbone gears and right-angle spiral-bevel gears. Spur gears are used on occasion, particularly in FIGURE 1 Spiral-bevel gear, right-angle vertical FIGURE 2 Four-speed change gear, variable-speed FIGURE 1 Spiral-bevel gear, right-angle vertical FIGURE 2 Four-speed change gear, variable-speed low-power, low-speed pump drives. Straight bevel and hypoid gears are also occasionally used in right-angle drives. As in the...

Hgs

* Head must be less than 600 ft stage (180 m stage) Materials B Cast iron casing bronze impeller cast iron bronze rings C All cast iron DR Carbon steel casing cast iron impellers G All 12 chrome (CA-15 or CA-6NM) H Carbon steel case 12 chrome impellers (CA-15 or CA-6NM) J Cast iron case bronze impellers bronze rings L All cast iron with 12 chrome rings NM 1- or 2-chrome barrels 12 chrome impeller (CA-15 or CA-6NM) S All 316 stainless (CF-3M) * Head must be less than 600 ft stage (180 m stage)...

Wnq

FIGURE 19 Single stage double suction reactor feed pump, 12,000 horsepower (8950 KW) (Flowserve Corporation) FIGURE 19 Single stage double suction reactor feed pump, 12,000 horsepower (8950 KW) (Flowserve Corporation) More detailed information on other nuclear power plant pumping services is given in Subsection 9.14.1. High-Speed, High-Pressure Boiler Feed Pumps As steam pressures rose to 3000 and even to 4500 lb in2 (200 to 310 bar) the total head that was required to be developed by the pump...

H H Benjes Sr W E Foster D A House

Sewage is defined as the spent water of a community. Although it is more than 99.9 pure water, it contains wastes of almost every form and description. Raw sewage, when fresh, is gray and looks something like dirty dishwater containing bits of floating paper, garbage, rags, sticks, and numerous other items. If allowed to go stale, it turns black and becomes very malodorous. About 25 of the waste matter of normal domestic sewage is in suspension the remainder is in solution. Sewage contains many...

Hydraulic Conditions

Low-Head Pumps For low-head pumps, up to approximately 150 ft (46 m), the installation must be carefully checked to prevent cavitation during periods of low-head operation. This is particularly important during one-pump operation on a parallel system. For FIGURE 13 A sealed room in a coal mine housing three 1000 HP (746 kW) bronze constructed pumps (Hazleton Pumps, Inc.) FIGURE 13 A sealed room in a coal mine housing three 1000 HP (746 kW) bronze constructed pumps (Hazleton Pumps, Inc.)...

Fi F2 F3 F4 F5

Friction loss calculations are normally based on a reference pulp temperature of 95 F (35 C). The flow resistance may be increased or decreased by 1 percent for each 1.8 F (1 C) below or above 95 F (35 C), respectively. This may be expressed as follows where T pulp temperature ( F), or F2 correction factor for pipe roughness. This factor may vary due to manufacturing processes of the piping, surface roughness, age, etc. Typical values for PVC and stainless...

187

To maintain internal clearances at the wearing rings, it is usually desirable to limit the shaft deflection under the most adverse conditions to between 0.005 and 0.006 in (0.127 and 0.152 mm). It follows that a shaft design with a deflection of 0.005 to 0.006 in will have a first critical speed of 2,400 to 2,650 rpm. This is the reason for using rigid shafts for pumps that operate at 1,750 rpm or lower. Multistage pumps operating at 3,600 rpm or higher use shafts of equal stiffness (for the...

S H

Three typical arrangements for determining the cavitation characteristics of pumps are illustrated in Figure 5. In Figure 5A, the suction is taken from a sump with a constant-level surface. The liquid is drawn first through a valve (throttle) and then through a section of pipe containing screens and straightening devices, such as vanes and baffles. This setup will dissipate the turbulence created by the suction valve and will also straighten the flow so the pump suction flow will be relatively...

Groundwater Wells

Site Selection Foremost among the factors that must be considered in selection of a site for a proposed well are local regulations governing proximity to such potential contaminants as cesspools, privies, animal pens, or abandoned wells. Also to be considered is the effect on adjacent wells if wells are located too close together, excessive head losses may result. Types of Pumps Used The two basic types of pump used in groundwater wells are vertical turbine, line shaft pumps, and submersible...

Applications Of Airoperated Diaphragm Pumps

General Diaphragm pumps are ideally suited for handling abrasive slurries because 1) the liquid velocity through the check valves and pumping chambers does not exceed the FIGURE 13 ARO air-operated double-diaphragm pump with ball check values (Ingersoll-Rand Fluid Products) FIGURE 13 ARO air-operated double-diaphragm pump with ball check values (Ingersoll-Rand Fluid Products) FIGURE 15 Three basic types of check valves FIGURE 15 Three basic types of check valves pipeline velocity and 2) the...

Got

Operations, 12.16 dam wearing rings, 2.120 damping coefficients, 2.267 Darcy-Weisbach formula, 8.33 data sheets, RFQs, 11.11 datum, horizontal vertical shaft pumps, 2.328 DC motors, 6.3, 6.8 PM brusless, 6.10, 6.12 SCR power supply drives, 6.123 shunt-wound, 6.8 SR brushless, 6.13 dealloying, 5.5 dealuminification , 5.6 debris removal, 10.14-10.16 deep well eductors, 4.38 deep well marine cargo pumps, 9.242-9.243 deep well turbine irrigation pumps, 9.46 defective bearings, 2.406 deflection,...

110

Follow the tracer lines in Figure 33 and read directly example 6 Calculate the frictional head loss for 100 ft (30.48 m) of 20-in (50.8-cm), Schedule 20,19.350-in (49.15-cm) ID, seamless steel pipe for 109 F (42.8 C) water flowing at a rate of 11,500 gpm (2612 m3 h). Use the Darcy-Weisbach formula. V - -r X 0.408 - X 0.408 12.53 ft s (pipe ID in inches)2 19.352 ' YD 12.53 X 19.35 242 ft s X in FIGURE 32 Relative roughness and friction factors for new, clean pipes for flow of 60 F (15.6 C) water...

Exhaust Systems

An engine consumes a large volume of air for combustion, and that volume must be removed after combustion. It is necessary that the exhaust back pressure be kept at a minimum while this volume is being removed. The exhaust piping should be properly sized, and long sweep elbows should be employed if necessary. Unless the back pressure is kept low, the following conditions can result High combustion temperatures with increased maintenance High jacket water temperatures Crankcase sludging with...

Principal Types Of Pumps

Most of the pumps in nuclear service are one- or two-stage centrifugal motor-driven pumps. Both vertical and horizontal types are used. Charging, safety injection, feedwater, and other high-head pumps are usually multistage motor-driven centrifugal units. Some requiring high power are turbine-driven. Double-suction designs are frequently used for RHR pumps, where service requires operation at low available NPSH. Reciprocating pumps find limited service in nuclear plants for make-up flow, seal...

Chemical Pump Standards

In 1962, a committee of the Manufacturing Chemists Association (MCA) reached agreement with a special committee of the Hydraulic Institute on a proposed American Standards Association (ASA) standard for chemical process pumps. This document was referred to as the American Voluntary Standard or the Manufacturing Chemists Association Standard. In 1971, it was accepted by the American National Standards Institute (ANSI) and issued as ANSI Standard B123.1. This ANSI standard was renumbered in 1974...

Uses Of Water

Classifications History has shown that significant concentrations of population have always occurred where a water supply was readily available. Accordingly, technology has been developed to make full use of the available supply, not only for domestic use but also for public, commercial, industrial, and agricultural consumption. Domestic usage consists of water used for household purposes. The amounts used for such purposes vary with the standard of living of the consumers, the quality of the...

Further Reading

ASME Hydro Power Technical Committee. The Guide to Hydropower Mechanical Design. HCI Publications, Inc., 1996. Daugherty, R. U, and Ingersoll, A. C. Fluid Mechanics. McGraw-Hill, New York, 1954. Henry, L. F. Selection of Reversible Pump Turbine Specific Speeds. Paper presented at meeting on pumped-storage development and its environmental effects, University of Wisconsin, September 1971. Roth, H. H., and Armbruster, T. F. Starting Large Pumping Units. Allis-Chalmers Eng. Rev. 31 (3X1966)....

05 3 68 35 15 85 78

Double suction. bHF is head after filing. cShutoff head. dDue in part to changes in pump casing. eDue in part to rounding of inlet blade tips. Source Flowserve Corporation FIGURE 19 Effect of overfiling at inlet on the velocity triangle just inside the blades FIGURE 19 Effect of overfiling at inlet on the velocity triangle just inside the blades is the velocity of the approaching liquid as seen by an observer moving with the blade. The angle 8 between w0 and w s the angle of attack, which...

Data Required For Turbine Selection

The turbine supplier should have the following information in order to select the best combination of size and type runner 1. Head available, head range, and head duration. 2. Power and speed required to drive pump. FIGURE 12 Sound level readings taken 3 ft (0.9 m) from main shaft. Hydraulic losses are approximated output in kilowatts X (1.00 turbine efficiency). (From L. F. Henry Selection of Reversible Pump Turbine Specific Speeds. Paper presented at meeting on pumped-storage development and...

Frederic W Buse

The principle of a magnetic drive pump is the elimination of the seal or packing in an overhung pump (Figure 1) and cutting the shaft in two at the seal location (Figure 2a). On the inner or wet end half of the shaft (Figure 2b), an inner magnet assembly (a) is placed on a shaft (b) supported by product lubricated bearings (c). On the other cut portion of the shaft, an outer magnet assembly (d) is placed on the power shaft (e). Between the inner and outer magnet assemblies, a static seal (f)...

Definition Of Terms

A definition of standard ejector terminology is as follows Ejector General name used to describe all types of jet pumps that discharge at a pressure intermediate between motive and suction pressures. Eductor A liquid jet pump using a liquid as motive fluid. Injector A particular type of jet pump that uses a condensable gas to entrain a liquid and discharge against a pressure higher than either motive or suction pressure principally, a boiler injector. Jet Compressor A gas jet pump used to boost...

Ships Service Pumps

Priming System For Centrifugal Pumps

FUEL-OIL TRANSFER PUMPS A fuel-oil (FO) transfer pump is used to remove fuel oil from one or more of a vessel's FO storage tanks and to transfer the oil to settling tanks, to other storage tanks (that is, to adjust the list, trim, or stability of the vessel), or to an above-deck connection through which the oil can be directed ashore or to another vessel. Most vessels have at least two pumps that can be used to transfer fuel oil. Although horizontally and vertically mounted multiple-screw...

J E Cygnor

The operating characteristics and reliability of aircraft fuel pumps are absolutely critical with respect to the performance and the safety of flight of today's gas turbine-powered commercial and military aircraft. With a large commercial airliner carrying upwards of 50,000 gallons (189,000 liters) of fuel on a long range flight, making fuel the single heaviest load the aircraft must handle, the importance of intelligent and safe processing of this fuel load is clearly evident. The aircraft...

Paul Cooper Raymond B Furst Adiel Guinzburg

Liquid-fueled rocket engines have been used on all the major launch vehicles, including the large, first-stage booster rockets as well as the upper stages of those same vehicles, and various smaller vehicles such as the lunar lander. The propellant pumps are major components of the engine. They pump a) the oxidizer, usually liquid oxygen, and b) the fuel, which is usually liquid hydrogen, up to the high pressures needed to feed the combustion processes. In the past, a widely used fuel was...

B B 1 jCwhm29

Where j is a coefficient with a proposed default value of unity. Another point concerns the evaluation of V50 and M for the middlings. The methods of Eqs. 24 and 25 are basically applicable but d50 and d85 must now refer to the middlings fraction only, rather than the whole grading curve. For very broad well-distributed grad-ings the middlings will simply be a slice between 0.003 in. (0.075 mm) and 0.018D. Here it may be possible to assume that d50 is the geometric mean of the two diameter...

Selection Theory

Power Brake horsepower (bhp) is a function of a pump's capacity, differential pressure, and mechanical efficiency. It is an essential criterion for selecting the drive components but is not valuable for pump selection. A large pump operating well below its design rating can meet the same horsepower requirements as a smaller pump running at a higher speed. Unless the application requires a derated pump, it is usually more economical to select a pump at the upper end of its design rating. The...

T

As the design of the eye, the hub and shroud profiles, and the blading. A preliminary design was also made of the vaned diffuser and return vanes, following the guidelines presented in the foregoing Design Procedures subsection. The result is a representative machine to which the following paragraphs continually refer. Blade-Vane Combinations Certain numerical combinations of impeller blades and diffuser vanes (or inlet guide vanes, where they are employed) have been shown to have acoustic...

Gear Materials And Heat Treatment

Two of the most important factors in dictating the success or failure of a gear set are the choice of material and heat treatment. This is especially true for gears designed for higher power. American Gear Manufacturers Association (AGMA) ratings for gear strength and durability are dependent on the choice of material and heat treatment. It is often possible to reduce the size of the gear box substantially by simply changing from low-hardened or medium-hardened gears (about 300 Brinell) to...

1

Because ratios are involved, it is convenient to replace specific weight with specific gravity (Pi - Ps)(sp. gr.2) (P2 - Ps)(sp. gr.i) When the suction and motive fluids are the same, no gravity correction is required and Eq. 2 becomes where H1 Hs operating head, ft (m) H2 Hs discharge head, ft (m) Entrainment relates the mass (flow rate) of motive fluid and suction fluid

Types Of Wear

Rotating equipment, including pumps, can suffer from damage as a result of mechanisms unrelated to corrosion. The relative motion between parts that are in close proximity to each other can produce wear when these components come into contact with one another. Catastrophic damage may occur if the parts make contact under high loading conditions or when foreign bodies are entrapped between the rotating and stationary components. An accelerated material loss or catastrophic seizure of these...

Wearing Rings

Design Wear Ring Centrifugal Pump

Wearing rings provide an easily and economically renewable leakage joint between the impeller and the casing. A leakage joint without renewable parts is illustrated in Figure 39. To restore the original clearances of such a joint after wear occurs, the user must either (1) build up the worn surfaces by welding or metal spraying, or (2) buy new parts. The new parts are not very costly in small pumps, especially if the stationary casing element is a simple suction cover. This is not true for...

Fixed Versus Variable Flows

Balanced Fixed Displacement Vane Pump

A fixed displacement hydraulic pump is used to drive the fixed-displacement hydraulic motor when a fixed water pump flow is desired. The drive shaft of a fixed-displacement vane pump (see Figure 9) is keyed to a rotor and revolves with it. Rectangular varies fit into slots in the rotor. As the rotor turns, the vanes are forced out by centrifugal force to FIGURE 9 Principle of fixed-displacement balanced-vane pump FIGURE 9 Principle of fixed-displacement balanced-vane pump make continuous...

Variable Speed Pump Bypass Considerations

Large horsepower pumps are often powered by steam turbines or with motors connected through a variable speed coupling. The effect of decreased speed and discharge head is to reduce the minimum flow requirement for the pump. Therefore, if the minimum required bypass flow is calculated and sized with the pump at normal operating speed and pressure, the bypass flow will be adequate when the pump is operated at lower speeds. Warning If a constant backpressure device such as a backpressure regulator...

Pump Duties

Pumps are used for filling, emptying, transferring, dosing and mixing. They are also used to convey the process fluid through plant items with a high resistance to flow, such as membrane filters and heat exchangers. In general, pumping should not harm any solids in the liquid, and delicate shear-sensitive products must be handled gently. The choice of a particular pump depends on consideration of a number of factors. These include capacity, delivery pressure, and suction conditions. The...

Siphons

Operation As previously defined, the term siphon refers to a jet pump utilizing a condensable vapor to entrain a liquid and discharge to a pressure intermediate between motive and suction pressure. The principal motive fluid is steam. In an eductor, the high-pressure motive fluid enters through a nozzle and creates a vacuum by jet action, which causes suction fluid to enter the mixing chamber. The siphon of Figure 19 is identical to the eductor of Figure 6 except that, unlike the eductor, the...

4

FIGURE 2 Section of single-stage turbine and governor system (Elliott) FIGURE 2 Section of single-stage turbine and governor system (Elliott) FIGURE 3 Typical turbine overspeed trip arrangement (Dresser-Rand). FIGURE 3 Typical turbine overspeed trip arrangement (Dresser-Rand). valve or of a separate steam valve only after the pressure being sensed by the controller has changed. Even when a control system is furnished, a speed governor is also normally furnished. The speed governor is set for a...

Pipe Screens And Strainers

Except for special designs for handling slurries and other solids, most pumps are limited in their ability to handle dirt, trash, and solids of any size down to microparticles. Pump passageways (volutes, diffusers, impellers) handle generally spherical objects up to a sticking size, but a severe problem may be caused by dust-size particles that lodge in sleeve bearings, bushings, and wear rings and cause either rapid wear or rotation seizure. A wet-pit source may never be quite free from some...

V

G fluid weight density, lbf ft3 (N m3) pg. (1N 1 kg-m s2). 8* displacement thickness of the boundary layer, ft (m). 80* displacement thickness of the zero-pressure-gradient boundary layer, ft (m), ( 0.002 X for turbulent boundary layers at n 1 cs in typical centrifugal pumps). e absolute roughness height, ft (m) e2 fraction of impeller discharge meridional area (that is, the area normal to the velocity component Vm 2) that is not blocked by the thickness of the blades and the boundary layer...

References And Further Reading

American National Standard for Sealless Centrifugal Pumps, ANSI HI 5.1-5.6-2000, Hydraulic Institute, Parsippany, NJ www.pumps.org. 2. Hydraulic Institute ANSI HI 2000 Edition Pump Standards, Hydraulic Institute, Parsippany, NJ www.pumps.org. 3. Sealless Pumps for Petroleum, Heavy Duty Chemical, and Gas Industry Services, API Standard 685, 2000, American Petroleum Institute, 1220 L Street, Northwest, Washington, D.C. www.api.org. 4. Eierman, R. A User's View of Sealless Pumps Their Economics,...

References

TAPPI Technical Information Sheet (TIS) 408-4. Technical Association of the Pulp and Paper Industry, Atlanta, Georgia (1981). 2. K. Molter and G.G. Duffy, TAPPI 61, 1, 63 (1978). 3. Hydraulic Institute Engineering Data Book, 2nd Edition, 1990, Hydraulic Institute, Parsippany, NJ www.pumps.org. 4. K. Molter and G. Elmqvist, TAPPI 63, 3, 101 (1980). 5. W. Brecht and H. Helte, TAPPI 333, 9,14A (1950). 6. R. E. Durat and L. C. Jenness, TAPPI 39, 5, 277 (1956). 7. K. Molter, C. G. Duffy and Al...

Valves

For the final control element, conventional and traditional valves serve for on-off control in pump systems. They also cover much of the modulation need. In recent years, modulating control in demanding services has required development of special control valves, actuators, and accessories. System dynamic characteristics, corrosion, erosion, noise, and costs have influenced the development. Operation and Valve Types The on-off operation of pump valves serves for 1. Isolation of a pump...

Capacity

FIGURE 15 Method of determining maximum pump power for two boiler-feed pumps operating in parallel the frictional losses in the discharge. If, as it should be, the design capacity of the pump is chosen as the maximum capacity that can be expected under emergency conditions, there can be no further increase under any operating conditions since the pressure requirement corresponding to an increased capacity would exceed the design pressure of the pump. Even when the design pressure includes a...

List Of Contributors

Able, Stephen D., B.S. (M.E.), MBA, M.S. (Eng) Section 3.6 Diaphragm Pumps Senior Engineering Consultant, Ingersoll-Rand Fluid Products, Bryan, OH Addie, Graeme, B.S. (M.E.) Subsection 9.16.2 Application and Construction of Centrifugal Solids Handling Pumps Vice President, Engineering and R& D, GIW Industries, Inc., Grovetown, GA Arnold, Conrad L., B.S., (E.E.) Subsection 6.2.3 Fluid Couplings Director of Engineering, American Standard Industrial Division, Detroit, MI

191m

AThe w' represents the maximum mass in weight units that could act on the bearing. or the film cavitates and decreases to atmospheric pressure as the lubricant releases entrapped air. With respect to stability, cavitation is a more desirable condition than the development of negative pressure. From an examination of Figure 1, it can be seen that the negative pressure pulls the journal in an orthogonal direction and increases the cross-coupling. The more eccentric the bearing, the larger the...

Cooling Systems

Cooling is essential in all internal combustion engines because only a small portion of the total heat energy of any fuel is converted to useful energy. The remainder is dissipated into FIGURE 5A Gasoline engine performance curves (A) maximum, (B) intermittent, (C) continuous ratings of engines with accessories (Waukesha Motor) FIGURE 5A Gasoline engine performance curves (A) maximum, (B) intermittent, (C) continuous ratings of engines with accessories (Waukesha Motor) the coolant, exhaust, and...

Outlet Port

FIGURE 14 Displacement calculation dimensions for an internal vane pump FIGURE 15 Displacement calculations for an external circumferential piston pump FIGURE 15 Displacement calculations for an external circumferential piston pump formed on the interior surface of the body chamber. The equation can be used for most single-rotor positive displacement pumps with an appropriate selection of the numerical values for R1 and R2. For example, in the vane-in-body pump, R1 is the minimum radius of the...

Construction

Basic Types As indicated in the introduction, three major types of screw pumps exist The second and third types are available in two basic arrangements, single-end and double-end. The double-end construction (see Figure 8) is probably the best-known version, as it has been by far the most widely used for many years because of its relative simplicity and compactness of design. Double-End Screw Pumps The double-end arrangement is basically two opposed, single-end pumps or pump elements of the...

Cost

For many pumping applications, cast iron is the preferred material for pump casings when evaluated on the basis of cost. For single-stage pumps, cast iron usually has sufficient strength for the pressures developed. For corrosive or hazardous petroleum products, it may be necessary to specify cast steel or cast stainless steel. The concern with cast iron when handling hazardous fluids is that the material is inherently brittle and could fail suddenly in a catastrophic manner with no prior...

Damping On A Structure Of Centrifugal Pump

Critical Damping This is the minimum damping for which a vibrating system has no vibratory motion. For analysis purposes, damping is expressed as a percentage of critical damping. The amplification of input motion, or magnitude of response, is inversely proportional to the damping ratio of the vibrating system. Figure 1 shows responses obtained for damping ratios which vary from 0.5 to 10 of critical damping. Damping Damping is the dissipation of energy in a vibrating system. Damping is a...