CEMA 705-2004 Conveyor Performance nTerminology.pdf

1、ConveyorPerformanceTerminologyCPDF Version - 2004CEMASTANDARDNO. 705ISBN 1-891171-61-5Conveyor EquipmentManufacturers AssociationFor Information on Company Membershipvisit the CEMA Web Site athttp:/www.cemanet.orgCEMA ORGANIZATIONAL CHARTSAFETY NOTICEThe Conveyor Equipment Manufacturers Association

2、has developed Industry Standard Safety Labelsfor use on the conveying equipment of its member companies.The purpose of the labels is to identify common and uncommon hazards, conditions, and unsafepractices which can injure, or cause the death of, the unwary or inattentive person who is working ator

3、around conveying equipment.The labels are available for sale to member companies and non-member companies.A full description of the labels, their purpose, and guidelines on where to place the labels on typicalequipment, has been published in CEMAs Safety Label Brochure No. 201. The Brochure is avail

4、ablefor purchase by members and non-members of the Association. Safety Labels and Safety LabelPlacement Guidelines, originally published in the Brochure, are also available free on the CEMA WebSite at http:/www.cemanet.org/CEMA_Safety_Pg.htmPLEASE NOTE: Should any of the safety labels supplied by th

5、e equipment manufacturer becomeunreadable for any reason, the equipment USER is then responsible for replacement and location ofthese safety labels.Replacement labels and placement guidelines can be obtained by contacting your equipment supplieror CEMA.ConveyorChainControls PalletizersMeet in March

6、and/or SeptemberConferenceStrategic PlanningInsuranceMeetingsMarketing/MembershipStatisticsFinance and BudgetPast PresidentsBulk HandlingSectionCommitteesUnit HandlingSectionEngineering ConferenceConveyor ChainPerformance TerminologyUnit Handling StandardsIdlersPulleysBeltSystemsScrewConveyorsBelt M

7、anualAccessoriesSafety ControlsTerms andDefinitionsInternationalStandardsMeets Each JuneScrewConveyorsBulk HandlingComponentsand SystemsGeneral Bulk Handling SectionBulkAccessoriesUnit Handling Conveying SectionCOMMITTEES BOARD OF DIRECTORS OFFICERSFOREWORD AND ACKNOWLEDGMENTSThis standard, Conveyor

8、 Performance Terminology, was prepared by the Performance TerminologyCommittee of the CEMA Engineering Conference. The objectives and purposes for publishing this standardinclude:A. Encourage uniform usage and understanding of performance terminology used in the conveyingfield.B. Assist in providing

9、 appropriate information for the selection and application of proper engineeringpractice in the field of materials handling as accomplished through usage of conveyor equipment.C. Provide a source or basis of information related to characteristics, features and conditionsinherent to the practices of

10、materials handling through usage of conveying equipment.Throughout this standard, preferred terms are followed by their definitions. Alternate terms in commonusage are listed and cross-indexed back to the preferred term in each case.Utilitization of Conveyor Performance Terminology, as published her

11、ein, is completely voluntary. Thispublication may be adhered to in its entirety, in part, or not at all, depending upon agreement of the partiesinvolved.For definitions of terminology which are not included herein, review the following references:A. CEMA Terms and Definitions (Standard No. 102).B. C

12、EMA Classification and Definitions of Bulk Materials (Book No. 550).C. ANSI/ASME B20.1, Safety Standard for Conveyors and Related Equipment.Legal terms and definitions are not within the scope of this publication.The Conveyor Equipment Manufacturers Association gratefully acknowledges the advice, as

13、sistance,and constructive criticisms afforded by the members of the committee and their companies. Without theirrespective contributions, preparation of this standard would not been have possible.CONVEYOR EQUIPMENT MANUFACTURERS ASSOCIATION6724 Lone Oak Blvd.Naples, Florida 34109(239) 514-3441Web SI

14、te: http:/www.cemanet.orgDISCLAIMERThe information provided in this document is advisory only. These recommendationsare provided by CEMA in the interest of promoting safety in the work place. Theserecommendations are general in nature and are not intended as a substitute for athorough safety program

15、 Users should seek the advise, supervision or consultation ofqualified engineers or other safety professionals. Any use of this document, theinformation contained herein, or any other CEMA publication may only be made withthe agreement and understanding that the user and the users company assume fu

16、llresponsibility for the design, safety, specifications, suitability and adequacy of thesystem component, or mechanical or electrical device designed or manufactured usingthis information. The user and the users company understand and agree that CEMA,its member companies, its officers, agents and em

17、ployees shall not be liable in anymanner under any theory of liability for the user or users reliance on theserecommendations. The users and the users company agree to release, hold harmlessand indemnify CEMA, its member companies, successors, assigns, officers, agentsand employees from any and all

18、claims of liability, costs, fees (including attorneysfees), or damages arising in any way out of the use of this information. CEMA and itsmember companies, successors, assigns, officers, agents and employees make norepresentations or warranties whatsoever, either express or implied, about theinforma

19、tion contained in this document, including, but not limited to, representationsor warranties that the information and recommendations contained herein conform toany federal, state or local laws, regulations, guidelines or ordinances.CONVEYOR PERFORMANCE TERMINOLOGYPrepared byThe Performance Terminol

20、ogy Committeeof theCEMA Engineering ConferenceCopyright 2004Conveyor Equipment Manufacturers AssociationCONVEYOR PERFORMANCE TERMINOLOGY1ACCEPTANCEAcknowledgment by the purchaser (or user) that equipment or services provided are suitable foraccommodating the intended function.The term “acceptance” a

21、s it applies to legal documents, such as purchase orders, is not within thescope of this definition.ACCESSIBILITYEase of access or approach to equipment for operation, inspection, maintenance, and lubrication.The term accessibility is not itself definitive. “Proper” accessibility depends upon the eq

22、uipment use,the function of the equipment, the space limitation, the environment, the relationship to otherequipment, the need for safe operation, and other considerations which require a mutual understandingbetween vendor and user.ADJUSTMENTSee FIELD ADJUSTMENT, RUN-IN. Also, see Takeup, Conveyor T

23、erms and Definitions, CEMAStandard No. 102.ALIGNMENTThe position of parts or components in relation to each other-such as, but not limited to, in a straightline, at a specified angle, in the same plane, horizontal, vertical, parallel.It is recognized that the performance of conveyors and related equ

24、ipment depends on careful alignmentduring assembly and installation. It is also recognized that parts of components aligned during factoryassembly should be checked for alignment and adjustment made if necessary during installation.Field adjustment of components, rollers, troughers, and shaft assemb

25、lies should be limited to thatadjustment supplied in the components, or as indicated on the drawings, specifications, or installationoperation manuals.In case of thermal expansion, there should be an agreement between the user and the vendor thatwhen thermal expansion affects the equipment, proper e

26、xpansion devices should be employed tomaintain alignment.In general, the vendor should specify the limits of alignment. If it is necessary to deviate from thespecified limits, the deviations shall be agreed upon between user and vendor.It is also recognized that specifications commonly use a number

27、of modifying words, such as “proper”,“acceptable”, “suitable”, “careful”, “normal”, “good”, “duly”, “operating”, and “working”, with respect tosuch function as alignment. Within the scope of these definitions, such modifiers shall all be taken tomean “within the limits recommended by the vendor”, “w

28、ithin the specific numerical limits set by theusers specifications” or, lacking these, to mean “sufficient so that the aligned elements will operatein such a manner that the equipment will perform the intended function.”CONVEYOR PERFORMANCE TERMINOLOGY2APPROVALThe concurrence or acceptance which rat

29、ifies or confirms an existing understanding as to terms,construction, method of operation, or other items.Approvals should be written or otherwise recorded to avoid disagreement or misunderstanding.It is common practice to provide dimensional and/or functional drawings for approval as part of aconve

30、yor or equipment sale. Approval drawings are submitted for the purpose of transmitting orcommunicating dimensional and other pertinent technical data for the users concurrence.Normally, drawings submitted for approval are of a general nature and show, as in the case ofmechanical drawings, such items

31、 as clearance dimensions, workpoints, foundation loads,anchorbolt size and location, power requirements, capacity, direction of travel and speed, and specialprotective coatings. Electrical, hydraulic, pneumatic, and other schematic drawings are sometimessubmitted for approval. The obligation to furn

32、ish drawings for approval should not obligate the vendorto furnish standard drawings that are considered proprietary by the vendor.AUTOMATICSelf-acting and/or self-regulating mechanism that performs a predetermined function. The termautomatic is frequently misused to imply some degree of control sop

33、histication or automation. Specificdescription of the intended automatic function is necesary for a proper understanding.BACKCHARGEAny charge to a vendor arising from unanticipated labor and/or material cost as a result of claimed oralleged nonperformance.BACKLEGGINGThe term applied to material elev

34、ated in a bucket elevator, en masse conveyors, and similar typeequipment, which does not discharge when the conveying medium reaches the discharge spout, butfalls into the return section.Variations in the consistencies and volume of the material feed to the conveying medium and locationsof discharge

35、 spouts can result in backlegging. Improper adjustment of the discharge spout throatplate or maintenance thereof is a frequent cause of backlegging. Improper design and/or operatingspeed can cause this condition.Acceptable performance results when delivery of material is at uniform rate equivalent t

36、o designcapacity without excessive fallback of material.To determine if excessive backlegging is occurring, check for buildup in return section and/or excesspower demand.CONVEYOR PERFORMANCE TERMINOLOGY3BATCHA quantity of material handled or processed in one cycle or lot. In some industries, a batch

37、 is referredto as a wave.BELT ALIGNMENT(See ALIGNMENT)BELT CLEANERA device (hydraulic, mechanical, pneumatic, sonic or a combination) for removing residual liquidsand/or solid materials from the return run of a conveyor belt. Dependent upon the nature of thematerial being removed, certain auxiliary

38、equipment such as collection sumps or exhausting equipmentmay be required. No amount of efficiency of removal is implied due to variables in the materialhandled, surface type and condition of the conveyor belt, and maintenance of belt cleaning equipment.The belt cleaner, if specified in the original

39、 contract, shall be approved for the application jointly bythe user and vendor.BELT TRAININGAlignment of an operating conveyor belt by means of, but not limited to, the adjustment of structuralor mechanical components or the addition of special devices to control the path of the belt. Self-training

40、devices are not an integral part of a belt conveyor unless so specified.A properly trained belt should not be considered a permanent condition. Belt elongation, componentwear, build up of material on the belt, on mechanical parts, or in loading chutes, and other changingconditions may require period

41、ic retraining for maintenance of proper belt alignment.Also, direction of movement of material being loaded onto a conveyor belt must be so controlled thatbelt training will not be adversely affected. It should be recognized that this control often requires fieldadjustment or modifications, such as

42、the addition of baffles.A belt is considered trained when it maintains its relative position on its terminal pulleys and remainswithin the confines of the carrying surface without being loaded or with loads evenly distributed onthe conveying surface. The edges of the belt should not rub the conveyor

43、 structure, roller brackets orother surfaces not designed for restricting lateral belt motion.A belt is allowed to move from side to side on its terminal pulleys so long as it returns to approximatelythe same position on the pulleys after making a complete cycle.On reversible belt conveyors, a belt

44、does not necessarily retain the same position when it is reversed.However, the same limits as described above apply.I n order to be considered trained, a belt should maintain its position as described above for a periodof time agreed upon by user and vendor.BIN CAPACITY(See CAPACITY 1.2 )CONVEYOR PE

45、RFORMANCE TERMINOLOGY4BIN LEVELThe elevation of bulk material within a bin at a point where the material contacts the bin wall. Thevolume of material in the bin will depend on the bin level, as well as the conformation and attitude ofthe surface of the material (i.e., cone up, cone down, water level

46、).The maximum bin level will be the top location of a level indicating device or, in the absence of sucha device, the highest point of the bin side for material while taking into account the angle of reposeand flow characteristics of the material.Any stated capacity for the bin will be based on this

47、 bin level criteria and will be a volumetricdetermination, unless otherwise defined by contract.(See CAPACITY 1.2)BLENDThe physical combination or intermingling of two or more ingredients, the result of which ishomogeneous within limits as established by the industry served. The accuracy of the blen

48、d isdependent upon the precision and stability of the measuring devices used in its preparation.Blends are described by indicating the amount of each ingredient related to the whole, measured byan agreed upon method of analysis.Certain types of blends may become separated when conveyed or elevated.

49、When this condition isdetrimental, it must be so specified by the user.The terms blend and mix are not interchangeable. Misunderstanding can result from improper selectionof terms used to describe a condition. Caution is to be exercised in selection of proper terminologyfor defining the condition under consideration.(See MIX)BUCKET ELEVATOR CAPACITY(See CAPACITY 1.1)BUCKET ELEVATOR HEIGHTThe vertical dimension from the lowest point to the highest point on the elevator.BUCKET ELEVATOR CENTERSThe distance between the centerline of the footshaft and the centerline of the headshaft alo