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Intentionally left blank AN AMERICAN NATIONAL STANDARD Specification for Thermoplastic and Thermoset Polymer Material Horizontal End Suction Centrifugal Pumps for Chemical Process ASME B73 5M 1995 Ame[.]

REAFFIRMED 2007 FOR CURRENT COMMITTEE PERSONNEL PLEASE E-MAIL CS@asme.org Intentionally left blank AN AMERICAN NATIONAL STANDARD Specification for Thermoplastic and Thermoset Polymer Material Horizontal End Suction Centrifugal Pumps for ChemicalProcess ASME B73.5M-1995 American Society of Mechanical Engineers 345 East 47th Street, New York, N.Y Date of Issuance: November 30, 1995 This Standard will be revised when the Society approves the issuance of a new edition There will benoaddendaor written interpretations of the requirements of this Standard issued to this edition ASME is the registered trademark of The American Society of Mechanical Engineers This code or standard was developed under procedures accredited as meeting the criteria for American National Standards The Consensus Committee that approved the code or standard was balanced to assure that individuals from competent and concerned interests have had an opportunity to participate The proposed code or standard was made available for public review and comment which provides an opportunity for additional public input from industry, academia, regulatory agencies, and the public-at-large ASME does not "approve," "rate," or "endorse" any item, construction, proprietary device, or activity ASME does not take any position with respect to the validity of any patent rights asserted in connection with any items mentioned in this document, and does not undertake to insure anyone utilizing a standard against liability for infringement of any applicable Letters Patent, nor assume any such liability Users of a code or standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, is entirely their own responsibility Participation by federal agency representative(s) or person(s) affiliated with industry is not to be interpreted as government or industry endorsement of this code or standard ASME accepts responsibility for only those interpretations issued in accordance with governing ASME procedures and policies which preclude the issuance of interpretations by individual volunteers No part of this document may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher Copyright 1995 by THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS All Rights Reserved Printed in U.S.A (This Foreword is not part of ASME 873.5M-1995.) Advances in the technology of polymers have allowed manufacturers to offer- these materials in lieu of or as an alternative to alloy metals Polymer industrial pumps have been offered since the 1970s As more pump manufacturers had products available, it was recognized that there were no pump standards for pressure, temperature, capacity, or mechanical features In 1986, the ASMEB73 Committee established a rule committee to develop a new standardfor reinforcedcompositematerialhorizontal end suction centrifugal pumps forchemical process Thisstandard was to befor pumpswith nonlinear polymers (excluding solid ceramics and/or carbon) The standard was to have the same envelope,pressure-capacity,andmechanical design featuresforshaft deflectionand bearing life of pumps conforming to ASME B73.1M The development of this standard progressed rapidly after the 1991 revision of ASME B73.1M was completed The title was then changed to Specification for Thermoplastic and Thermoset Polymer Material Horizontal End Suction Centrifugal Pumps for Chemical Process The polymers listed in this Standard are those most commonly used for the chemical process, with the option for manufacturers to offer alternative materials The pressuretemperature limits are based on the polymers currently available The limits depend on the concentration and temperature of the specific liquid As the development of the Standard proceeded, the latest applicable features of ASME B73.1M were added, as well as a criterion for outside mechanical seals which is not found in ASME B73.1M Suggestions for improvement of this Standard will be welcome They should be sent to The American Society of Mechanical Engineers, Secretary, B73 Committee, 345 East 47th Street, New York, NY 10017 This Standard was approved as an American National Standard on July 10, 1995 111 Intentionally left blank ASME STANDARDS COMMITTEE B73 Chemical Standard Pumps (The following is the rosterof the Committee at the time of approval of this Standard.) OFFICERS R J Hart, Chair G W Sabol, Vice Chair C J Gomez, Secretary COMMITTEE PERSONNEL A R Budris, Alternate, I n A-C Pump F W Buse, lngersoll Dresser Pump Co G C Clasby, The Duriron Co R W Estep, Rhone-Poulenc AG Co R J Hart, E.I DuPont de Nemours & Co D C Hughes, Dow, USA, E&CS Division L J Kitchens, BWAP International Inc P T Lahr, Consultant A L Lyons, Department of the Navy, Naval Construction Battalion Center R H Monroe, Jr., Monsanto Co A N Nichols, Gridlestone Pumps, Ltd J C Osborne, Goulds Pumps, Inc R S Peck, Durametallic Corp G W Sabol, Union Carbide Corp A E Stavale, I T A-C Pump J C Swalley, Alternate, E.I DuPont de Nemours & Co D M Threlkel, NEMA V Intentionally left blank CONTENTS Foreword Standards Committee Roster Scope AlternativeDesigns NomenclatureandDefinitions Design andConstructionFeatures GeneralInformation References 111 V 1 1 11 11 Figures Cylindrical SealChamber Self-ventingTapered SealChamber BackplateWithClampRing Backplate With Seal Chamber Seal ChamberFaceRunout Seal ChamberRegister Concentricity ShaftSleeve Runout 9 Tables MinimumWorkingPressure PumpDimensions Baseplate Dimensions ApproximatePerformance of Standard Pumps (50 Hz) ApproximatePerformance of Standard Pumps (60 Hz) 12 14 16 17 vii Intentionally left blank ASME 873.5M-1995 THERMOPLASTIC AND THERMOSET POLYMER MATERIAL HORIZONTAL END SUCTION CENTRIFUGAL PUMPS FOR CHEMICAL PROCESS externalflushing.Improvedmeantimebetween planned maintenance is the benefit of clean and cool running mechanical seal chambers 4.6.3 Tapered Seal Chamber Taper bore chamber designs with a 4-5 deg taper offer the maximum heat transfer of seal generated heat to the pumped product.Thissealchamberdesignhelpseliminate gas entrainment around the seal during startlstop operations Gas bubbles can limit lubrication of the seal faces and cause a dry running condition Enlarged taper bore seal chambers also improve seal performance when used in applications where process fluids are close to their boiling points 4.6.4 Backplate Seal Chamber Outside mechanical seals areoften used with backplate designs and a clamp ring (see Fig 3) The bore in both these parts is sized to fit thestationary seatand is not controlled by this Standard Other types of seals (inside, double, tandem) areused with backplate designs (see Fig 4) 4.6.5 Seal Chamber Runout Mechanicalseal performance is highly dependent on the runout conditions that exist atthemechanical sealchamber Types of runout having significant effect on seal performance include: (a) Seal Chamber Face Runout This is a measure of the squareness of the seal chamber face with respect to the pump shaft It is measured by mounting a dial indicatoron the pump shaft and measuring the total indicator runoutat theface of the seal chamber The maximum allowable runout is 0.08 mm (0.003 in.) FIM (See Fig ) (b) Seal Chamber Register Runout Provisions shall be made for centering the glandwith either an inside or outside diameter register This registershall be concentric with the shaft or sleeve and shall have a total indicator runout reading no greater than 0.13 mm (0.005 in.) FIM (See Fig 6.) (c) ShafrlShafr Sleeve Runout This is a measure of runout at the shaft or shaft mounted sleeve O.D with respect to a fixed point in space It is usually measured by mounting a dial indicator at a fixed point in space, such as the face of the seal chamber, and measuring theFIMrunoutattheshaftmounted sleeve O.D.The maximum allowableshaft sleeve runout is 0.05 mm (0.002 in.) (See Fig 7.) 4.6.6 Space Requirements Space in the various seal chamber designs shall provide for one or more of the following configurations of cartridge or noncartridge seals: (a) single inside mechanical seals, balanced or unbalanced, with or without a throat restriction device (throat bushing); (b) double seal, balanced or unbalanced, inboard and outboard; (c) outsidemechanicalseal,balanced or unbalanced, with or without a throat bushing; (d) tandem seals, either balanced or unbalanced 4.6.7 Throat Restriction Devices In single seal applications where seal life is not meeting normal design specifications, the following should be considered The velocity of the flush needs to be increased to remove particles or fibers from the seal chamber The sealing fluid pressure is to be raised to maintain a positive controlled flow into the process When isoIating the seal chamber from the processfluid is necessary, an external liquid is to be injected into the seal chamber In eachof these cases aclose clearance throat restriction device is required A typical throat restriction device is a replaceable bushing that utilizes a nominal I.D clearance to the shaft sleeve Throat bushings are designed to fit standard stuffing box configurations with a throat shoulder that the bushing can be installed against Fixed bushings are normally pressed into the stuffing box core Floating bushings are mechanically suspended to allow for shaft deflection and closer clearances 4.6.8 Gland (a) Bolting Pumps shall be designed for four gland bolts (b) Gasket The gland-to-stuffing box gasket or 0ring used for mechanical seals shall be confined on the atmospheric side to prevent blowout.Machine surfaces of seal chamber bore, face, and gland may be coated with the base polymer to prevent liquid bypass around the gasket (c) Materials of Construction (I) The gland material shall be compatible with the liquid pumped (2) Bolts, studs, and nuts shall be a 300 series stainless steel or other specified corrosion-resistant material 4.7 Inserts and Connecting Fasteners Inserts shall be totally encapsulated except for the mating threaded surface The insert material shall be compatible with the mating fastener The installed insert shall be capableof being tested to200% of the assembly values appIied to the connecting fasteners or in-service values Manufacturers shall state nominal fastener torque in the instruction manual If re- THERMOPLASTIC AND THERMOSET POLYMER MATERIAL HORIZONTAL END SUCTION CENTRIFUGAL PUMPS FOR CHEMICAL PROCESS / / x \ I ' \ R \ s 0.81 mm (0.032 in.) \ / 1.0 mm (0.040 in.) Typical Deburred Chamfer FIG BACKPLATE WITH CLAMP RING I ASME B73.5M-1995 THERMOPLASTIC AND THERMOSET POLYMER MATERIAL HORIZONTAL END SUCTION CENTRIFUGAL PUMPS FOR CHEMICAL PROCESS ASME B73.5M-1995 / x \ R s 0.81 rnrn (0.032 in.) 1.0 m m (0.040 in.) Typical Deburred Chamfer Dimension Designation Radial Clearance x Minimum AA - AB A05 - A80 A90 - A120 x = 19.05 rnm (3/4 in.) x = 22.22 rnrn (7/8in.) x = 25.40 rnm (1.0 in.) FIG BACKPLATE W I T H SEALCHAMBER THERMOPLASTIC AND THERMOSET POLYMER MATERIAL HORIZONTAL END SUCTION CENTRIFUGAL PUMPS FOR CHEMICAL PROCESS ASME B73.5M-1995 quired, the manufacturer shall demonstrate that the inserts are capableof a minimum of 20 assemblies at 200% proof values Torquing shall be done by the manufacturer's prescribed progressive sequential instructions 4.8 Bearings FIG 4.8.1 Design Two antifriction bearing assemblies shall be provided, one assembly free to float within the frame to carry radial thrust only, and the other assembly arrangedtocarrybothradialand axial thrust SEAL CHAMBER FACE RUNOUT 4.8.2 Bearing Life Bearing life shall be selected in accordance with ANSUAFBMA andANSI/ AFBMA 11 Pump sizes AA through A70 shall have a minimum I; bearing life of 17,500 hr at maximum load Pump sizes A80 and larger shall have a minimum L bearinglife of 17,500 hrat designload (See para 4.5.4.) +- 4.8.3 End Play End play in the shaft from the thrust bearing shall be at a minimum, the definition of which depends upon internal clearances and mechanical seal requirements w FIG 4.8.4 Sealing Bearinghousing shall be constructed to protect the bearings from water, dust, and other contaminants The housing shall be designed so it can be machined to accept a bearing isolator SEAL CHAMBER REGISTER CONCENTRICITY 4.8.5Lubrication Oillubricationfor the ball bearing shall be standard The bearing housings shall be tapped for constant level oil feed regulator orlevel indicator Bearing housings and end covers shall have bossescast so oil mist connectionscanbeadded Other methods of lubrication may be specified Oil levelers and sight glass should be capable of being mounted on either side of the bearing housing The bearing frame shall be marked with an external permanent indication of the proper oil level Bullseye sight glass shall notbe less than in NPT connection,with 1in NPT preferred.View post shall provide a center of the indication of the proper operating oil level for the bearing frame FIG SHAFT SLEEVE RUNOUT 4.8.6 Drain The bearing housing shallbe provided with a tapped and plugged drain hole at its lowest point A Y8 in NPT pipe size drain is preferred; Y4 in NPT minimum is acceptable ASME 873.5M-1995 THERMOPLASTIC AND THERMOSET POLYMER MATERIAL HORIZONTAL END SUCTION CENTRIFUGAL PUMPS FOR CHEMICAL PROCESS 4.9 Materials of Construction 4.12 Dimensions The materials of construction of the major pumpage-wetted parts shall be identified Pumps with the following materials of construction are applied to chemical services Due to the continuous change in state-of-the-art available composites, only typical lists of materials are shown (a) Thermosetting composite shall be able to withstand continuous service with the liquid pumped at temperaturesnot exceeding 120°C (250"F), unless otherwise qualified by themanufacturer.Thermosetting materials include: (I) vinyl esters (2) epoxies (3) plyesters (b) Thermoplastic composite shall be able to withstand cor?tinuous service with the liquid pumped at temperaturesnot exceeding 120°C (250°F) Thermoplastic materials include: (I) CPVC (chlorinated polyvinyl chloride) (2) PVC (polyvinyl chloride) (3) polypropylene (4) polyethylene (5) polyester (6) PVDF (polyvinylidene fluoride) (7) PTFE (polytetrafluoroethylene) (8) PPS (polyphenylene sulfide) (9) PEEK (polyetheretherketone) (c) Unwetted cast iron parts may be ASTM A 278 (0r.A 48 for nonpressure containing parts) (not to be used for hazardous liquids) (d) Unwetted cast carbon steel parts shall be ASTM A 216 Grade WCB (or cast ductile iron ASTM A 536 for nonpressure containing parts) Pump and baseplate dimensions shall conform to Tables and 4.10 Corrosion Resistance The materials of the wetted components shall be mutually selected by the user and pump manufacturer to provide a minimum life of two years (when operated in accordance with the manufacturer's instructions andpressure-temperature limitsin the specified pumped fluid) 4.13 Miscellaneous Design Features 4.13.1 Safety Guards A coupling guard, in accordance with ASME B15.1, shall be furnished on all units that include a pump and driver mounted on a common baseplate Guarding of the shaft between the seal chamber and bearing bracket shall be furnished if thereare hazardous attachments on the shaft If the shaft or sleeve is smooth, additional protection is not required A n auxiliary deviceto control spray from seal chamber leakage shall be provided when specified 4.13.2 Threads Threadedparts such as bolts, nuts,and plugs shall conform tothe applicable American National Standards 4.13.3 Lifting Rings A lifting ring or other equivalent device shall be provided to facilitate handling the frame andassociated assembly if its mass exceeds 27 kg (60 Ib) Eyebolts on motors are not suitable for lifting the entire pump motor assembly The pump manufacturer's manual shall specify proper lifting instructions 4.13.4 Tapped Openings All tapped openings, including those in the mechanical seal gland which may be exposed to the pumped fluid under pressure, shall be plugged with threaded plugs rated for the working pressure Plugs in contact with'the pumped fluid shall be of a material that is compatible with the liquid pumped All tapped openings in the mechanical seal gland shall be identified to designate their purpose This designation should be molded or etched immediately adjacent to the opening Designations are F for flush, D for drain, Q for quench, and V for vent Steam heating must not exceed temperature limits of the material 4.13.5 Identification The manufacturer's part identification number and material designation shall be cast, molded, or clearly die stamped on the casing, cover, and impeller 4.11 Direction of Rotation Direction of rotation shall be clockwisewhen viewed from the coupling end An arrow showing the direction of rotation shall be provided, either cast or molded on the casing or seal chamber or stamped on a plate of durable construction affixed to the pump in a prominent location 4.13.6 Adapter The bearing frame adapter shall be designed to resist a torque equalto or greater than the ultimate torque strength of the pump shaft at the coupling end 10

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