14913

FIGURE 4 Response of LJL operating pressure ratio Nop and operating flow ratio Mop to jet pump design area ratio b FIGURE 4 Response of LJL operating pressure ratio Nop and operating flow ratio Mop to jet pump design area ratio b increases the slope of the theoretical N(M) curve at low M values. At operating M values, however, this effect is negligible. Finding b as a Function of Nop or Mop Figure 4 presents Nop(b) and Mop(b) for the recommended K friction coefficients of .05, 0, and .20. The...

Steam Pump Capacity

The flow to the discharge system is termed the pump capacity. The capacity, usually expressed in U.S. gallons per minute (cubic meters per minute), is somewhat less than the FIGURE 23 Simplex plunger pump with forged steel cylinder (1) steam cylinder with cradle, (2) steam cylinder head, (3) steam cylinder foot, (7) steam piston, (9) steam piston rings, (11) slide valve, (12) piston valve, (18) steam chest, (19) steam chest cover, (22) steam chest head, (24) valve rod stuffing box gland, (26)...

Mej

Babbitted bearings, 2.149 babitts, 2.273 backflow high-energy pump cavitation, 2.86 preventers, 2.143 backup systems, magnetic bearings, 2.279 backward curved blades, centrifugal pumps, 2.331 balance couplings, 6.182 seals, 2.200-2.201, 2.211 balanced piston valves, duplex steam pumps, 3.44 balancing drum disk units, hydraulic balancing devices, 2.129-2.131 ball bearings, 2.149 angular contact, 2.151 double-row angular contact, 2.152 electric motors, 6.17 lubrication, 2.153 sealed, 2.150...

Diagnosis from Visual Examination of Damage

Bearing damage Static radial loads in excess of the bearing rating will cause cracking of the balls or rollers and the races in rolling element bearings. In the case of sleeve bearings, the bearing metal will be worn in one direction only and the journal will be worn uniformly. If the opposite is true (that is, the bearing is worn uniformly and the journal excessively in one direction), the cause of the failure is most likely unbalance or a bent shaft and not excessive bearing loads. shaft...

Coupling Methods For Pump Applications

Direct Coupling Pumps are frequently directly coupled to motors, and where the pump is not close-coupled, it is usually coupled by means of a flexible coupling. The use of a flexible coupling permits minor misalignment (angular and parallel) between motor and pump shafts. The use of some older style flexible or solid couplings could cause severe radial and axial loads on the motor bearings. Since the development of the flexible disk couplings, the earlier coupling designs have largely...

P

Packaged gas turbine drivers, 6.95 packaged gear drives, 6.152 packed plunger metering pumps, 9.313 packing glands, 2.147 packing rings, 2.184 packing seals, 2.183 packings abrasives, 2.192 air leakage, 2.192 chemical pumps, 9.122 coefficients of friction, 2.187 compression, 2.184 continuous coil, 2.193 lantern rings, 2.141 materials used, 2.187-2.188 power pumps, 3.26 pressure issues, 2.190-2.191 rotary pumps, 3.124 sleeves, 2.138 slurry pumps, 9.357 temperature issues, 2.192 packless stuffing...

1

FIGURE 1 Pump classification type identification (Courtesy of the American Petroleum Institute1) 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...

Lav

FIGURE 24 Transient system head as a result of liquid acceleration and system friction when a propeller pump is started with an open valve FIGURE 24 Transient system head as a result of liquid acceleration and system friction when a propeller pump is started with an open valve where L length of constant-cross-section conduit, ft (m) AY velocity change, ft s (m s) g acceleration of gravity, 32.17 ft s2 (9.807 m s2) Ai time interval, s To calculate the time to accelerate a centrifugal pump from...

Cost

For many water and other noncorrosive services, bronze satisfies these criteria and, as a result, is the most widely used impeller material for these services. Bronze impellers should not be used for pumping temperatures in excess of 250 F (120 C). This is a limitation imposed primarily because of the differential rate of expansion between the bronze impeller and the steel shaft. Above 250 F (120 C), the differential rate of expansion between bronze and steel will produce an unacceptable...

Impeller

FIGURE 70 A sleeve for pumps with an overhung impeller FIGURE 71 A seal arrangement for the shaft sleeve to prevent leakage along the shaft FIGURE 71 A seal arrangement for the shaft sleeve to prevent leakage along the shaft ferred. For pumps subject to abrasives, hardened chrome or other stainless steels give good results. In most applications, a hardened chromium steel sleeve will be technically adequate, and the most economical choice. For severe or unusual conditions, coated sleeves are...

2

FIGURE 11 Viscous fluid effects on centrifugal pumps adapted from Hydraulic Institute ANSI HI 2000 Edition Pump Standards, Reference 7. FIGURE 11 Viscous fluid effects on centrifugal pumps adapted from Hydraulic Institute ANSI HI 2000 Edition Pump Standards, Reference 7. activity within the pump. (At the critical point, the liquid and gas phases are identical, and therefore both have the same specific volume.) An example is the pumping of liquid hydrogen, for which an inducer is unnecessary...

Pump

FIGURE 5 Typical automatic bypass system based on pump differential head The bypass pressure reducing orifice handles the high velocity and erosive forces of the bypass flow. However, the handling of cavitation and flashing by this fixed restriction is limited. The orifice is sized to operate properly at one bypass flow condition. At low flows, the orifice does not provide the correct pressure reduction as designed. The check valve is placed in the main line, as shown in Figure 4, to prevent...

Special Multiphase Applications

Screw pumps have been used with gas-entrained applications for many years, but recent process changes in oil field technologies have created requirements for pumping multiphase fluids, containing more than just nominal amounts of gases. In many oil well applications, the liquid oil flow eventually degenerates into all sorts of difficult multiphase mixtures of oil, gas, water, and sand. In the past, it was common for the gas to be separated and flared off at the well head with only the liquid...

Mechanical Problemsbearings

Excessive radial thrust in singlevolute pumps 78. Excessive axial thrust caused by excessive wear at internal clearances or, if used, failure or excessive wear of balancing drive 79. Wrong grade of grease or oil 80. Excessive grease or oil in rolling element bearing housings 82. Improper installation of rolling element bearings such as damage during installation, incorrect assembly of stacked bearings, use of unmatched bearings as a pair, and so on 84. Moisture contaminating lubricant 85....

Mechanical Performance

The mechanical performance of a pump would imply only the rotating mechanical masses, with no consideration given to hydraulic (process) effects. The rotating masses (impellers, sleeves, nuts, coupling, bearings, seals, and so on) can be examined as pure mechanics. A person concerned with mechanical performance should be intimately familiar with pump design, construction, and maintenance to be successful. In discussing the mechanical performance of centrifugal pumps, two examples will be used....

Use Of Gears With Pump Drives

The main use of gearing in pump drives is to reduce the speed of the prime mover (a motor or an engine) to the level applicable to the pump. In some cases, however, the gears are employed to step up the speed because the pump must operate at a speed higher than that of the prime mover. There are other jobs that gear drives must perform with pump units. For instance, a vertical pump may be combined with a prime mover that must operate horizontally (as in the case of a diesel engine). A...

Direct Contact Type

Facilities are called accumulators and are illustrated in Figure 1. A modern accumulator is buffered by a large pressurized gas (mostly air) cushion. Until about 1960, the direct-contact surface between gas and liquid virtually precluded the use of oil in accumulator installations for larger presses. Gas diffuses into oil under pressure. When oil is discharged from the press at the end of the pressing cycle, the gas begins to bubble out of the liquid the liquid foams, and because of its large...

50 75 100 125 130 135

FIGURE 5C Diesel engine performance curves (A) maximum, (B) intermittent, (C) continuous ratings of engines with accessories (Waukesha Motor) the tubes. The fan is driven either by the engine or by an auxiliary source of power (Figure 7). An engine in a fixed outside installation can be cooled without much difficulty. Certain factors must be considered, such as ambient temperature, direction of the prevailing wind, and presence of foreign airborne materials. In high temperatures (usually above...

Pump Testing

Since the first time a device was used to pump or lift water, pump testing of one sort or another has occurred. Each improvement in pumping devices was accepted only after being tested, which was the proof of its worthiness. As pumping equipment has become more refined, so has the art of pump testing, both in the shop or laboratory and in the field. For very large pumps, model testing is being used to develop the optimum refinement in prototype design. Every pump, regardless of size or...

Steam Power Plant Pumping Services

Pumps are very important components of a steam electric power plant. The major applications are the condensate, boiler-feed, heater drain, and condenser circulating pumps. The all-inclusive category of miscellaneous pumps includes such a variety of services that it merits being broken down into its components and included in a representative listing. Table 1 provides such a listing for conventional (fossil fuel) steam power plants. The list is not necessarily complete but is reasonably...

Steam Power Plant Cycles

Power is produced in a steam power plant by supplying heat energy to the feedwater, changing it into steam under pressure, and then transforming part of this energy into mechanical energy in a heat engine to do useful work. The feedwater therefore acts merely as a conveyor of energy. The basic elements of a steam power plant are the heat engine, the boiler, and a means of getting water in the boiler. Modern power plants use steam turbines as heat engines except for very small plants,...

Info

FIGURE 33 For a given pressure drop DP across a valve, the globe will show a higher pressure at the vena contracta, making it more likely that cavitation difficulties will be avoided when the vapor pressure is high. FIGURE 33 For a given pressure drop DP across a valve, the globe will show a higher pressure at the vena contracta, making it more likely that cavitation difficulties will be avoided when the vapor pressure is high. depends on valve type ball and butterfly valves have higher...

Description Of The Design Of Airframe Boost Pumps

Figures 3 and 4 present a cross section view and a photograph of an electric motor-driven boost pump assembly that is used on a commercial airliner. This pump utilizes a snorkel inlet. The design of this pump incorporates cartridge type pump and discharge valve modules that greatly enhances the maintainability of these pumps. The elliptical shaped main housing is a semi-permanent assembly in the airframe fuel tank. The pump modules are easily removable from it without draining the fuel tank...

Liquid Cylinder

FIGURE 3 Schematic of the liquid end of a reciprocating pump during the discharge stroke LIQUID CYLINDER'* FIGURE 4 Schematic of a double-acting liquid end LIQUID CYLINDER'* FIGURE 4 Schematic of a double-acting liquid end to a liquid cylinder liner by pistons with packing. It has two suction and two discharge valves, one of each on each side of the piston. The piston is moved by a piston rod. The piston rod packing prevents liquid from leaking out of the cylinder. When the piston rod and...

Steam Consumption And Water Horsepower

After determining the proper size of other pump types, the next concern usually is to calculate the maximum brake horsepower so the proper size of driver can be selected. With a steam pump, the next step is usually to determine the steam consumption. This must be known to ensure that the boiler generating the steam is large enough to supply the steam required by the pump as well as that required for all its other services. To determine the steam consumption, it is necessary first to calculate...

Advantages

Although the original users of hydraulically driven water pumps were contractors, farmers, and open pit miners using mostly portable pumps, the system described here offers the advantage of permanent pump stations, such as might be used for municipal storm drainage (Figure 6) or massive irrigation or drainage works. The system is very simple. The power source can be located close to the pump or in a more accessible or protected area. Other advantages include the ability to vary the speed FIGURE...

Low Lubricity Fuel

The use of the pumped fuel as the lubricant for the pump and all components within the fuel system is an established and required practice. Unfortunately, there is no requirement for lubricity in the fuel specifications. Therefore, some knowledge of the minimum lubricity to be expected in the field is necessary. The key factor to determine is the lubricity of the fuel under boundary lubricating conditions for evaluating the wear characteristics of the gear tooth profiles and the fuel lubricated...

Economics And Pump Selection

The normal economic considerations of any continuous process apply equally well to pulp and paper mills, with a few points of difference. In pump installations, the improved cost figures that are possible from larger units are limited to some extent by the manufacturer's standard size units. Because the industry is capital intensive, the overriding factor in any pump installation is reliability. To achieve this, it does not necessarily follow that it is better to have two pumps installed, with...

Z2

Distance from inlet bell centerline to sloping floor b 0 to +10 degrees (Negative values of b, if used, require flow distribution devices developed through a physical model study) Angle of convergence from constricted area to bay walls aCross-flow is considered significant when VC > 0.5 VX average aCross-flow is considered significant when VC > 0.5 VX average cost. Actual pumps and valves should be used to create the flow in the pump pit, and extremes of flow and submergence should be...

Applications

Positive displacement pumps are especially suited for many solids-pumping applications because constant high pressures and good efficiency are achieved over the full range of pump capacities. Low relative velocities between abrasive liquid-solids mixtures and the pump parts minimize erosion. With centrifugal pumps, an increase in system resistance, such as a flow blockage caused by settled solids or the apparent viscosity increase characteristic of many slurries due to momentary capacity...

Dieseldriven Generators

Jacket-water circulating pumps A diesel engine that drives a generator is often furnished with an attached centrifugal-type jacket-water circulating pump that circulates freshwater through passages in the engine's cylinders and cylinder heads, the engine's tur-bocharger, and the engine's lubricating-oil cooler. In addition, the jacket-water system may include a preheater that is used to warm-up the water prior to engine start-up. When the jacket water is air cooled, it will also pass through a...

Subsurface Hydraulic Pumping System

A complete hydraulic system consists of a fluid cleaning system, a power pump (usually a triplex), surface controls, a subsurface hydraulic pump, and tubing connecting the surface power pump to the subsurface pump. (See Section 3.1 for a complete description of power pumps.) Figure 6 is a schematic drawing of a complete multiple-well hydraulic system. Because the pressurized power fluid supplies the energy needed to pump the well, the heavy sucker rod string and the heavy structure of the...

Types Of Vacuum Devices

Almost every commercially made vacuum-producing device can be used with systems in which pumps are primed by evacuation of air. Formerly water-jet, steam-jet, or air-jet primers had wide application, but with the increase in the use of electricity as a power source, motor-driven vacuum pumps have become more popular. Ejectors Priming ejectors work on the jet principle, typically using steam, compressed air, or water as the operating medium. A typical installation for priming with an ejector is...

Regulation Of Flow Rate

Flow rate variation ordinarily is accomplished by a change in pump head, speed, or both simultaneously. The flow rate and power input of pumps with specific speeds up to about 4000 (1.464) double suction increase with decreasing head, so the drivers of such pumps may be overloaded if the head falls below a safe minimum value. Increasing the head of high-specific-speed pumps decreases the flow rate but increases the power input. The drivers of these pumps should either be able to meet possible...

The Sucker Rod Pumping System

The sucker rod pumping system consists of a prime mover, a pumping unit, a polished rod with a stuffing box to seal off the pumped fluid pressure at the surface of the well, and a sucker rod string to transmit the reciprocating movement from the pumping unit to the sucker rod pump. The pumping unit is the mechanism that converts the rotary movement of the prime mover to the reciprocating movement needed to power the sucker rod pump. The sucker rod string consists of individual sucker rods of...

Types Of Controls

In order to use an electric motor to drive a pump, a means of starting and stopping the motor is required. The devices used for this purpose can be called controls. Only small perhaps up to two or three hp (kW) motors can be controlled with a simple on-off switch (starting from full rated line voltage). This is because when a motor is first started it produces no back EMF and will draw very high starting currents. If the load inertia is very high, the motor can overheat during the long...

Piping

Suction Piping The suction piping should be as direct and short as possible. If a long suction line is required, the pipe size should be increased to reduce frictional losses. (The exception to this recommendation is in the case of boiler-feed pumps, where difficulties may arise during transient conditions of load change if the suction piping volume is excessive. This is a special and complex subject, and the manufacturer should be consulted.) Where the pump must lift the liquid from a lower...

Theory

A steam turbine develops mechanical work by converting to work the available heat energy in the steam expansion. Heat and mechanical work, being two forms of energy, can be converted from one to the other. The heat energy is converted in two steps. The steam expands in nozzles and discharges at a high velocity, converting the available heat energy to velocity (kinetic) energy. The high-velocity steam strikes moving blades, converting the velocity energy to work. Because the total heat energy...

Ojl

Flow through one side allows cleaning of opposite basket while line is still in service. (1) positive flow diversion, (2) rapid switchover, (3) free-turning handwheels, (4) visual indication of valve position, (5) external acme threads, (6) internal access, (7) cover and clamp(s), (8) streamlined flow, (9) basket, (10) basket handle, (11) basket, (12) one-piece body construction (Andale) FIGURE 26 Duplex basket strainer. Flow through one side allows cleaning of...

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...

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...

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...

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...