concrete plant standards

7/28/2019 Concrete Plant Standards

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Twelfth Revision, November 2000

C O N T R O L S

P L A N T M I X E R S

Concrete

PlantStandardsof the Concrete PlantManufacturers Bureau

P L A N T S

Affiliated with:

CPMB 10


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2 CPMB 100-00 Concrete Plant Standards

Your Assurance of Quality!


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CPMB 100-00 Concrete Plant Standards 3

FOREWORD

The Concrete Plant Mixer Manufacturers Bureau (CPMB) is an organization composed ofcompanies directly involved in the design, manufacture and sale of concrete plants and componentsthereof. The function of the CPMB is to establish minimum standards for rating various components ofconcrete plants for the protection of and assurance to the user that the plated components of the plantsconform to these Standards. The CPMB also provides a means for mutual consideration of matterscommon to the concrete industry whereby concrete plant technology, user services, agency

specifications and related common problems can better be served through coordinated efforts of themembers of the CPMB and its Divisions.

The Control Systems Manufacturers Division (CSMD) of the CPMB is an organization composedof manufacturers directly involved in the design, manufacture and sale of controls for concrete batchingplants. The CSMD establishes minimum standards for rating control systems for concrete plants - Part2 of these Standards.

The Plant Mixer Manufacturers Division (PMMD) of the CPMB is an organization composed ofcompanies directly involved in the design, manufacture and sale of concrete plant mixers. The functionof the PMMD is to establish minimum standards for rating concrete plant mixers - Part 3 of theseStandards.

The Air Quality Manufacturers Division (AQMD) of the CPMB is composed of manufacturers

directly involved in the design, manufacture and sale of air quality equipment for concrete batchingplants. Standards for these components of concrete plants are under development.

INTRODUCTION

Members of the CPMB and its Divisions attach rating plates to components of concrete plants asallowed by these Standards. The rating plates serve to indicate that the component conforms to therequirements of these Standards. Rating plates for plant mechanical equipment may be attached toitems listed in Part 1 of these Standards.

Members of the CSMD attach rating plates to components of control systems for concrete plantslisted in Part 2 of these Standards.

Members of the PMMD attach rating plates to concrete mixers to specify the maximum mixingcapacity to standard sizes as indicated in Part 3 of these Standards. The rating plate on a concrete mixerdoes not guarantee that the mixer will mix concrete at the rated capacity under all actual fieldconditions, but that it meets the requirements for volumetric requirements in Table 3.1 of theseStandards.

Rating plates guarantee that components of concrete plants that have them attached conform to therequirements of these Standards established and unanimously agreed upon by all members of theCPMB and its Divisions. These methods continue to represent industry practice and are used by allmembers of CPMB, whose membership represents the majority of concrete plant manufacturers.

These standards provide useful tables, formulas and considerations, so that the purchaser who isconcerned with the actual performance can depend on these standards as a guide in the selection ofconcrete plant components. In addition these standards include rating criteria, methodology, formulasand available sizes of concrete plant components currently used by the industry.

Current Edition approved November 4, 2000, originally published March 1, 1960. Previous Edition, Eleventh Revision, September1, 1996.

Part 3 of these Standards was previously published as PMMD 100-96 Concrete Plant Mixer Standards of the Plant MixerManufacturers Division, Concrete Plant Manufacturers Bureau, Seventh Revision, April 17, 1996, originally published January 1, 1966.

See companion Standard CPMB 100M-00 for SI Units.


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4 CPMB 100-00 Concrete Plant Standards

PURPOSE

These Standards have been prepared for theinformation of users of concrete plant equipment,including plants, controls and plant mixers. They havebeen established pursuant to Articles VI-VII of theBylaws of the Concrete Plant Manufacturers Bureau todescribe and identify the products and combinations ofproducts manufactured or furnished by members ofthe Bureau, its Control Systems ManufacturersDivision and its Plant Mixer Manufacturers Division,and to standardize rated capacities, the basis fordetermining rated capacities, and certain other featuresof concrete plant components, control systems andplant mixers.

EFFECTIVE DATE

These revised Standards shall become effective onNovember 4, 2000. Members of the Bureau shall attachrating plates to all eligible equipment shippedthereafter and certified by them as complying withthese Standards. Equipment shipped prior toNovember 4, 2000 shall be subject to the Concrete PlantStandards in effect at time of shipment. Equipment

shipped prior to March 1, 1960 shall not be entitled to arating plate.

CERTIFICATION

A copyrighted rating plate furnished by the Bureaushall be attached to those eligible items of concreteplant equipment shipped by a member of the Bureau,its Control Systems Manufacturers Division and PlantMixer Manufacturers Division and certified by thecompany as complying with these Standards. Therating plate shall define size, capacity or performance.Each member of the Bureau shall execute annually the

following stipulation:

Our company hereby certifies that rating plates ofthe Concrete Plant Manufacturers Bureau have beenattached during the year just ended and will beattached in the forthcoming year to eligible items ofconcrete plant equipment which conform to theStandards of the Bureau and only to such eligibleitems.

This stipulation shall be signed by an authorizedofficer of the member company. Any membercompany shall furnish the Bureau, upon request,structural drawings, steel design computations andany other information pertinent to determining that

items of equipment conform to these Standards.

SCOPE

These Standards specify requirements for concreteplant, controls and plant mixer equipment eligible to bedesignated as standard by the Concrete PlantManufacturers Bureau.

GOVERNING UNITS

The values stated in inch-pound units are to beregarded as the standard. The SI (metric) equivalentvalues given in parenthesis are for information only.See CPMB 100M-00 for the version of this standard inSI units.

PART 1 Plant Mechanical Equipment

PART 2 Plant Control Systems

PART 3 Plant Mixer Equipment

Concrete Plant Standards of the Concrete Plant Manufacturers Bureau

CPMB 100-00

Twelfth Revision - Effective November 4, 2000


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TABLE OF CONTENTS

1. Specifications for Equipment

1.1. Bins or Silos

1.1.1. Bins, Aggregate

1.1.2. Bins or Silos, Cement

1.1.3. Multiple Compartment Cement and FlyAsh Bin or Silo

1.1.4. Bins, Combination

1.2. Conveying Equipment

1.2.1. Belt Conveyors for Aggregates1.2.2. Bucket Elevators for Aggregates

1.2.3. Bucket Elevators for Cement

1.2.4. Other Conveyors for Cement

1.3. Batching Equipment

1.3.1. Scales

1.3.1.1. Scale Accuracy

1.3.1.2. Scale Lever Systems

1.3.1.3. Beam Scales

1.3.1.4. Dial Scale

1.3.1.5. Load Cell Systems

1.3.2. Batchers, General

1.3.2.1. Batchers, Aggregate

1.3.2.2. Batchers, Cement (CementitiousMaterials)

1.3.2.3. Batchers, Water

1.3.3. Water Meters

1.3.4. Dispensing Equipment for Admixtures

1.3.4.1. Admixture Batchers

1.3.4.2. Volumetric Admixture Dispensers

1.3.5. Accuracy for Batching

1.3.5.1. For Individual Batchers

1.3.5.2. For Cumulative Batchers With a TareCompensated Control

1.3.5.3. For Cumulative Batchers Without aTare Compensated Control

1.3.5.4. For Volumetric Batching Equipment

1.3.5.5. Range of Accuracy

1. SPECIFICATIONS FOR EQUIPMENT

The following items of equipment covered by theseStandards are eligible to have rating plates attached tothem:

batchers for aggregates,

batchers for cement or cementitious materials,

batchers for water,

bins for aggregates,

bins or silos for cement or cementitiousmaterials,

bins for both aggregate and cement orcementitious materials,

belt conveyors for aggregates,

bucket elevators for aggregates,

bucket elevators for cement or cementitiousmaterials,

other conveyors for cement or cementitiousmaterials.

Rating plates are not furnished for the followingitems of equipment covered by these standards:

water meters,

admixture batching equipment.

Items of equipment eligible to be designated asstandard shall conform to the applicable requirementsset forth hereafter in these Standards.

1.1. Bins or Silos. A bin or silo shall consist of a suitablecontainer for storing aggregates or cement andcementitious materials and, in the case of the latter,protecting it from moisture. Bins or silos shall bedesigned structurally in accordance with the currentspecifications of the American Institute of SteelConstruction.

1.1.1. Bins, Aggregate. Aggregate bins shall bestructurally designed to contain the rated capacity plusheaping, based on material weighing 110 lb/ft3 (1760kg/m3). Rated capacities, as shown on the rating plate,shall be stated in terms of cubic yards (m3) of binvolume at the bin water level. Bin water level shall bethe sum of water level volumes of each individualcompartment in the bin. In addition, rated capacitiesmay be stated in terms of cubic yards (m3) of heapedvolume. The heaped volume shall not exceed the

CPMB 100-00 Part 1 Plant Mechanical Equipment 1-1

Part 1 - Plant Mechanical Equipment



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lowest bin water level volume plus the volumerepresented by the frustum of a cone or pyramid abovethat water level, sloping from the perimeter of the binat an angle of 40 degrees from the horizontal, to avertical height equal to 25 percent of the minimumwidth of the bin at the lowest water level line. Ratedcapacities may also be stated in tons (metric tons) basedon material weighing 100 lb/ft3 (1600 kg/m3).

1.1.2. Bins or Silos, Cement. Cement bins or silos shallbe designed to contain rated capacity loads of materialweighing 94 lb/ft3 (1500 kg/m3). Rated capacity asshown on the rating plate shall be stated in terms ofcubic feet and cubic yards (m3) of gross air volume. Inaddition, they may be stated in tons, based on one ton,or 2000 pounds, equal to one cubic yard of partiallyaerated cement (one metric ton = 0.843 m3).

1.1.3. Multiple Compartment Cement and Fly Ash Binor Silo. Any multiple compartment bin or silo forstorage of fly ash and cement constructed after January1989, shall have a fly ash compartment with double

walls separating it from other compartments forcementitious materials. Such double walls shall beconstructed in a manner that permits detection ofleakage of the cementitious materials by manualinspection.

1.1.4. Bins, Combination. Bins for the storage of bothaggregates and cement shall be designed and theircapacities computed and stated on the rating plateseparately for aggregates and cement in accordancewith the applicable provisions of Paragraphs 1.1.1 and1.1.2 above.

1.2. Conveying Equipment. All conveyor capacities, as

shown on the rating plate, shall be based on theequipment being uniformly and continuously fed.

1.2.1. Belt Conveyors for Aggregates shall conform tothe current Standards of the Conveyor EquipmentManufacturers Association. Rated capacities, as shownon the rating plate, shall be stated in tons per hour(metric tons/hr), assuming the material to weigh 100lb/ft3 (1600 kg/m3).

1.2.2. Bucket Elevators for Aggregates shall have theirrated capacities, as shown on the rating plate, stated interms of tons per hour (metric tons/hr) computed byassuming that the buckets are filled to 75 percent of

their actual volume capacity with material weighing100 lb/ft3 (1600 kg/m3).

1.2.3. Bucket Elevators for Cement shall have theirrated capacities, as shown on the rating plate, stated interms of ft3/hr (m3/hr) computed on the assumptionthat the buckets are filled to 100 percent of their water-level capacity.

1.2.4. Other Conveyors for Cement, such as screwconveyors, slides and pumps shall have their rated

capacities as shown on the rating plate stated in termsof ft3/hr (m3/hr) based on the volumetric capacityrating by the manufacturer of the conveyor.

1.3. Batching Equipment shall provide that:

cement or cementitious materials shall bebatched by weight;

aggregates shall be batched by weight;

water shall be batched by weight or volume; powdered admixtures shall be batched by

weight; and

liquid admixtures shall be batched by weight orvolume.

1.3.1. Scales. Scales for batching shall consist of one ofthe following:

(1) A lever system suspending the weighingcontainer, and, by means of secondary levers,transmitting reduced loads to a beam scale withbalance indicator or a full reading springlessdial.

(2) A lever system as in (1) above with a single loadcell within the lever system as the primary loadindicator and the beam scale or dial assecondary load indicators.

(3) A lever system as in (1) above with either theprimary or secondary levers transmittingreduced loads to a single load cell and nothaving a beam scale or dial.

(4) A multiple load cell system directly supportingthe weighing container.

The construction shall conform to the applicable

sections of the NIST Handbook 44-96, Specifications,Tolerances and Other Technical Requirements forWeighing and Measuring Devices, except as hereinspecified. Methods other than those specificallydescribed in this paragraph, which meet all weighingtolerances and requirements to assure reliability asspecified in these standards, are acceptable.

1.3.1.1. Scale Accuracy. When scales are first installedthey shall be accurate to the basic tolerance valuesspecified in NIST Handbook 44-96 Section T.N.3.4. Thetolerance limit shall be 0.1% of the capacity of the scale.

1.3.1.2. Scale Lever Systems shall be so designed to

have a cross carrying capacity sufficient to support thefully loaded weighing container without loss ofaccuracy or abnormal wear and to have the center ofgravity of the gross load on the scale always betweenthe load supports. Scale lever pivots shall be hard,tempered, sharpened and gauged for sustainedaccuracy. The bearing loops shall be constructed withhardened bearing surfaces. Means shall be providedfor leveling, aligning, balancing and calibrating scalesystems in the field.

1-2 CPMB 100-00 Part 1 Plant Mechanical Equipment


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1.3.1.3. Beam Scales. Beams for indicating the loadshall include a zero balance beam, a balance indicatorand a weighing beam for each ingredient used in anybatch. Beams shall be precision constructed deviceswith properly hardened pivots and bearings capable ofholding positive alignment. All poises shall havepositive and accurate holding devices. All wearingparts of poises shall be hardened and protected againstcorrosion. The clear interval between beamgraduations shall not be less than 0.03 in. (0.76 mm).The balance indicator shall be sufficiently sensitive toshow movement when a weight of 0.1 percent of thescale capacity is placed in the batch hopper. Pointertravel shall show a minimum of 5 percent of the netrated capacity of the largest weigh beam forunderweight and 4 percent for overweight. A readilyadjustable mechanism shall be provided fordampening excessive oscillation of the indicatorpointer.

1.3.1.4. Dial Scale. A dial scale mechanism shall beenclosed so as to be dust-tight. The dial pointer shall

indicate the load in the batcher continuously from zerobalance to the scale capacity. The chart shall be ofdurable material to ensure good readability. Chartsused on the primary dial attached to the scale shallhave a minimum of 1000 graduations placed on acircular reading line with a clear interval of not lessthan 0.03 in. (0.76 mm).

1.3.1.5. Load Cell Systems shall be so designed to havea gross carrying capacity sufficient to support the fullyloaded weighing container without a loss of accuracyor abnormal wear and to have the center of gravity ofthe gross load on the scale always between the load

supports. A single load cell may be used with a scalelever system, or multiple load cells may be used tosupport a weighing container. Load cell supports shallbe designed to prevent any lateral or other nonaxialforces. Load cells shall be sealed for environmentalprotection. Load cell systems shall be designed to resist

(a) moisture,

(b) leakage,

(c) damage from overload or shock,

(d) drift from high voltage or high temperature,

(e) line noise or radio frequency interference.

A load cell system shall include a convenient meansto allow the operator to check the condition and properfunctioning of both the load cell circuit and the signalconditioning and load display circuit. A means may beprovided to automatically check these circuits on amore frequent basis. Digital weight indicators shall becapable of reading full scale capacity and a maximumweight indication of 0.1 percent of full scale capacity.Digital indications shall be clear, definite, accurate andeasily read under all conditions of normal operation.

1.3.2. Batchers, General. A batcher shall consist of asuitable container for weighing an ingredient forconcrete. Acombination of aggregates or a combinationof cements (or cement and other cementitiousmaterials) may each be considered as a singleingredient. Aggregates and cement or cementitiousmaterials shall not be weighed in the same batcher.Each batcher shall be equipped with a scale and alsowith the necessary mechanisms for its operation. Thecharging device shall be capable of stopping the flow ofmaterial within the weighing tolerances specified inthese Standards. Charging and discharging devicesshall not permit loss of materials when closed. Thedischarge device shall be capable of controlling the rateof flow of the material.

When furnished, vibrators, or other aids to chargingand discharging, shall be attached in such a mannerthat they will not affect accuracy of weighing.

The batcher shall be so designed and of suchcapacity that it will receive its rated load without the

weighed materials being in contact with the chargingmechanism.

The criteria to qualify batchers for rating plates arebased on minimum volumetric capacities.

Volumetric capacities may exceed the minimumrequirements. In use, the rated batcher capacity may beexceeded providing the load does not:

(a) exceed the scale capacity,

(b) overflow the batcher,

(c) affect the scale by the closing of the chargingdevice.

The rated batcher capacities in Column 1 of Table 1.1and Column 1 of Table 1.2 for aggregate andcementitious materials, respectively, are the standardsizes and are required to have rating plates attached.These rated capacities are stated in terms of the volumeof concrete produced in a single batch.

1.3.2.1. Batchers, Aggregate. Individual batchers shallbe rated separately at their maximum single batchcapacity rather than indicating the total batch resultingfrom the use of all batchers.

The minimum volume of the batcher in ft3 (m3),calculated from dimensioned drawings, shall be equalto its rated batcher capacity multiplied by 38 (1.407).(See Table 1.1).

The volume of the batcher shall be calculated on twobases, the lesser of which shall govern, as follows:

(a) based on an angle of repose for the aggregatesof 30 degrees from the horizontal measuredfrom the bottom of all charging mechanisms;or

(b) based on actual water level capacity.



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There shall be sufficient clearance above aggregatebatchers to permit convenient removal of overload.

The reading face capacity or the sum of weigh-beamcapacities of a scale on an aggregate batcher shall benot less than 3,300 lb/yd3 (1966 kg/m3) of rated batchercapacity.

1.3.2.2. Batchers, Cement (Cementitious Materials).The minimum volume of the batcher in ft3 (m3),calculated from dimensioned drawings, shall be 3 ft3

(0.085 m3) to allow for fluffing and variations in filling,plus 9 times the yardage rating (1/3 of the ratedcapacity of the plant in m3). (See Table 1.2).

Cement batchers shall be provided with a dust sealbetween the charging mechanism and the batcherinstalled in such a manner that it will not affect theaccuracy of weighing. The batcher shall be vented topermit escape of air. It shall be self-cleaning and may befitted with a vibrator to ensure complete discharge.

The reading face capacity or the sum of weigh-beamcapacities of a scale on a cement batcher shall be notless than 660 lb/yd3 (392 kg/m3) of rated batchercapacity.

It is recognized that mass concrete work for dams,etc., requires special rating based on a minimum of 350lb/yd3 (208 kg/m3).

The above volumes and scale capacities are notapplicable to individual batchers for cementitiousmaterials other than cement.

1.3.2.3. Batchers, Water. Scales for measuring the watermay be graduated either in pounds (kg) or U.S. gallons(L) or both.

The minimum volume of the batcher tank,calculated from dimensioned drawings, shall be notless than its rated batcher capacity. Any water batchershall have a volume providing not less than 40 U.S.gallons/yd3 (198 L/m3) of concrete to be produced in asingle batch.

The reading face capacity or the sum of weigh-beamcapacities of a scale on a water batcher shall be not lessthan 320 lb/yd3 or 38 gal/yd3 (188 kg/m3 or 188 L/m3)of rated batcher capacities.

1.3.3. Water Meters shall not be furnished with a rating

plate and shall conform to the Standards of theAmerican Water Works Association, except as hereinspecified. The metering equipment, in addition to themeter, shall include:

(1) A cut-off device capable of stopping the flowwithin the accuracy tolerances specified in theseStandards. The cut-off device shall be free fromleaks when closed;

(2) A strainer of a size and porosity as isrecommended by the meter manufacturer;

(3) A register integral with the meter or a separatedevice to indicate the volume batched, at anypoint in the metering operation;

(4) A volume setting device capable of being set toone gallon (3.8 L) increments, or a registercapable of being read to one gallon (3.8 L) orboth;

(5) Capability for field adjustment for purposes ofcalibration.

1.3.4. Dispensing Equipment for Admixtures.Admixture dispensing equipment furnished by theplant manufacturer shall not be furnished with a ratingplate but shall be subject to the followingspecifications: powdered admixtures shall be batchedby weight, liquid admixtures may be batched byweight or volume, and the specifications shall beapplicable only for dispensing admixtures having aminimum recommended dosage rate of one fluidounce (or more) per 100 lb (65 mL per 100 kg) ofcement; or for concentrated additives that have been

reconstituted to the point where the dosage rate is onefluid ounce (or more) per 100 lb (65 mL per 100 kg) ofcement.

The batching or dispensing devices shall be capableof repetitively controlling the batching of theadmixture to the accuracy tolerances specified in theseStandards. Piping for liquid admixtures shall be freefrom leaks and properly valved to prevent backflow orsiphoning.

A separate dispenser is recommended for eachadmixture, although multiple use of dispensingcontrols is permitted and compatible admixtures may

be stored in the same holding or checking reservoirafter batching and prior to introduction into the mixer.If, contrary to this recommendation, the samedispensing equipment is used for non-compatibleadmixtures, the common device shall be flushed at theend of each cycle.

1.3.4.1. Admixture Batchers. Scales for admixturebatchers may be graduated by weight or volume, withthe minimum graduation being the amount or weight ofthe admixture required per 100 lb (per 100 kg) of cement.

Admixtures that are compatible may becumulatively weighed in the same batcher providing

the accuracy of batching of each is equivalent to theaccuracy of batching required by these Standards wheneach is batched individually.

Liquid admixtures that are compatible may becumulatively weighed with the water providing thatthe accuracy of batching of each is equivalent to theaccuracy of batching required by these Standards wheneach is batched individually.

1.3.4.2. Volumetric Admixture Dispenser. Alladmixture dispensing equipment other than weigh



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batchers shall be classified as volumetric dispensers.All volumetric dispensers shall be used only for liquidadmixtures and each plant shall be equipped with thenecessary calibrated devices that will permitconvenient checking of the dispensed volume to therequired accuracy of the particular admixture.

The dispensing system shall include a device ordevices that shall either detect and indicate the

presence or absence of flow of the admixture, or detectand indicate the presence or absence of the admixture,or provide a convenient means of visually observingthe admixture in process of being batched ordischarged.

1.3.5. Accuracy for Batching for equipment covered bythese Standards shall be as follows:

1.3.5.1. For Individual Batchers, the followingtolerance values shall apply based on the required scalereading:

Cement and other Cementitious Materials(1)

1% of the required weight of materials beingweighed OR 0.3% of scale capacity, whichever isgreater

Aggregates -2% of the required weight of material beingweighed OR 0.3% of scale capacity, whichever isgreater

Water -1% of the required weight of material beingweighed OR 0.3% of scale capacity, whichever isgreater

Admixtures -

3% of the required weight of material beingweighed OR 0.3% of scale capacity, OR theminimum dosage rate per 100 lb (per 100 kg) ofcement, whichever is greater.

1.3.5.2. For Cumulative Batchers With A TareCompensated Control (see 2.1.4), the tolerances ofParagraph 1.3.5.1 shall apply based on the requiredweight of each material.

1.3.5.3. For Cumulative Batchers Without a TareCompensated Control (see 2.1.4.), the followingtolerances shall apply to the required cumulativeweight:

Cement and other Cementitious Materials orAggregates -

1% of the required cumulative weight ofmaterial being weighed OR 0.3% of scalecapacity, whichever is greater

Admixtures -3% of the required cumulative weight ofmaterial being weighed OR 0.3% of scalecapacity, OR the minimum dosage rate per 100 lb(per 100 kg) of cement as it applies to each type ofadmixture, whichever is greater.

1.3.5.4. For Volumetric Batching Equipment thefollowing tolerances shall apply to the required volume

of material being batched:Water -

1% of the required volume of material beingbatched OR 1 gallon (3.8 L), whichever is greater

Admixtures -3% of the required volume of materials beingbatched OR the minimum recommended dosagerate per 100 lb (per 100 kg) of cement, whichever isgreater.

1.3.5.5. Range of Accuracy. For ingredients batched byweight the accuracy tolerances required of the batching

equipment shall be applicable for batch quantitiesbetween 10% and 100% of scale capacity.

For water or admixtures batched by volume, therequired accuracy tolerances shall be applicable for allbatch sizes from minimum to maximum, as isdetermined by the associated cement or aggregatebatcher rating. (See Table 1.1).


(1) Other cementitious materials are considered to include fly ash,ground granulated blast furnace slag, and other natural ormanufactured pozzolans.


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12 19 0.54 0.375 0.528

1 38 1.08 0.75 1.056

112 57 1.61 1 1.407

2 76 2.2 1.5 2.11

3 114 3.2 2 2.81

4 152 4.3 3 4.22

412 171 4.8 3.5 4.93

5 190 5.4 4 5.63

6 228 6.5 4.5 6.33

7 266 7.5 5 7.04

8 304 8.6 6 8.44

9 342 9.7 7 9.85

10 380 10.8 7.5 10.56

11 418 11.8 8 11.26

12 456 12.9 9 12.67

13 494 14.0 10 14.07

14 532 15.1 11 15.48

15 570 16.1 11.5 16.19

16 608 17.2 12 16.89

(1) of plant in yd3 or m3 of concrete.(2) of volumetric space in an aggregate batcher.(3) see the companion standard, CPMB 100M.

Table 1.1

Standard Aggregate Batcher Sizesand Minimum Required Volumetric Capacity

in US Customary Units

Note: US Customary Sizes are Standard. SI (Metric) equivalentvalues are approximate and are only provided as information.

Standard US Customary Sizes NearestSI Size(3)

12 7.5 0.21 0.375 0.215

1 12.0 0.34 0.75 0.340

112 16.5 0.47 1 0.42

2 21.0 0.59 1.5 0.59

3 30.0 0.85 2 0.76

4 39.0 1.10 3 1.09

412 43.5 1.23 3.5 1.26

5 48 1.36 4 1.42

6 57 1.61 4.5 1.59

7 66 1.87 5 1.76

8 75 2.1 6 2.09

9 84 2.4 7 2.42

10 93 2.6 7.5 2.59

11 102 2.9 8 2.76

12 111 3.1 9 3.09

13 120 3.4 10 3.42

14 129 3.7 11 3.76

15 138 3.9 11.5 3.92

16 147 4.2 12 4.09

(1) of plant in yd3 or m3 of concrete.(2) of volumetric space in a cement or cementitious material batcher.(3) see the companion standard, CPMB 100M.

RatedCapacity,

yd3 ( 1)

Rated MinimumCapacity, Volume,

m3 ( 1) m3 ( 2)

Minimum Volume(2)

Standard, ft3 Approximate, m3

Table 1.2

Standard Cementitious MaterialBatcher Sizes and Minimum Required

Volumetric Capacity in US Customary Units

Note: US Customary Sizes are Standard. SI (Metric) equivalentvalues are approximate and are only provided as information.

Standard US Customary Sizes NearestSI Size(3)

RatedCapacity,

yd3 ( 1)

Rated MinimumCapacity, Volume,

m3 ( 1) m3 ( 2)

Minimum Volume(2)

Standard, ft3 Approximate, m3


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TABLE OF CONTENTS


2.1. Batching Controls and Systems

2.1.1. Manual Controls

2.1.2. Semi-Automatic Batcher Controls

2.1.3. Semi-Automatic Interlocked BatcherControls

2.1.4. Automatic Batcher Controls

2.1.5. Automatic Volumetric Controls

2.1.6. Manual Batching System

2.1.7. Partially Automatic Batching System

2.1.8. Semi-Automatic Batching System

2.1.9. Automatic Batching System

2.2. Batching Recorders, General

2.2.1. Graphic Recorder

2.2.2. Digital Recorder

2.2.3. Digital Batch Documentation Recorder

2.2.4. Digital Concrete Certification Recorder


The following items of equipment covered by theseStandards are eligible to have rating plates attached tothem:

semi-automatic batching control for anindividual batcher,

semi-automatic interlocked batching controlfor an individual batcher,

automatic batching control for an individualbatcher,

partially automatic batching system formultiple batchers and volumetric devices,

semi-automatic batching system for multiplebatchers and volumetric devices,

automatic batching system for multiplebatchers and volumetric devices,

recorders.

Rating plates are not furnished for the followingitems of equipment covered by these Standards:

manual batching controls,

manual batching systems.

Items of equipment eligible to be designated asstandard shall conform to the applicable requirementsset forth hereafter in these Standards.

2.1. Batching Controls and Systems. Batching controlsare that part of the batching equipment that providesthe means for controlling the batching device for anindividual material. They may be mechanical,hydraulic, pneumatic, electrical, etc. or a combinationof these means.

A batching system is a combination of batchingcontrols necessary to proportion the ingredients forconcrete. A batching system may consist of controls forbatching cement and aggregate only, if the mixingwater is not added at the batching plant. Volumetricadmixture batching controls are included in the scopeof these Standards only when they are a part of abatching system.

CPMB 100-00 Part 2 Plant Control Systems 2-1

Part 2 - Plant Control Systems


Control Systems Manufacaturers Division


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Batching controls or systems shall be so located withrespect to the batching equipment being controlled thatvisual monitoring for accuracy, calibration of controlsand manual batching can be accomplished. If manualbatching is not normally done, monitoring devicesshall be sufficiently accurate to detect an error equal tothe specified tolerance when a batch equal to the ratedsize of the batcher is batched.

Where batching controls or systems are remotelylocated with respect to the batching equipment andmanual batching is not normally done, monitoringdevices shall be sufficiently accurate to detect an errorequal to the specified tolerance when a batch equal tothe rated size of the batcher is batched.

Where batching controls or systems are remotelylocated with respect to the batching equipment,follower scales or other remote monitoring devicesmay be used for manual batching if they repeat thereading of the master scale within 0.2% of scalecapacity.

2.1.1. Manual Controls shall not be furnished with arating plate. Manual control exists when the batchingdevices are actuated manually with the accuracy of thebatching operation being dependent on the operatorsvisual observation of a scale or volumetric indicator.The batching devices may be actuated by hand or bypneumatic, hydraulic, or electrical power assists.

2.1.2. Semi-Automatic Batcher Controls shall befurnished with rating plates only when ingredients areweighed. This rating plate is to be used only for anindividual batcher control. When actuated by one ormore starting mechanisms, a semi-automatic batcher

control shall start the weighing operation of eachmaterial and stop automatically when the designatedweight of each material has been reached. Nointerlocks are required.

2.1.3. Semi-Automatic Interlocked Batcher Controlsshall be furnished with rating plates only wheningredients are weighed. This rating plate is to be usedonly for an individual batcher control. When actuatedby one or more starting mechanisms, a semi-automaticinterlocked batcher control shall start the weighingoperation of each material and stop automaticallywhen the designated weight of each material has been

reached, interlocked in such a manner that thedischarge device cannot be actuated until the indicatedmaterial is within the applicable tolerances.

2.1.4. Automatic Batcher Controls shall be furnishedwith rating plates only when ingredients are weighed.This rating plate is to be used only for an individualbatcher control. When actuated by a single startingsignal, an automatic batcher control shall start theweighing operation of each material and stopautomatically when the designated weight of each

material has been reached, interlocked in such amanner that:

(1) The charging device cannot be actuated untilthe scale has returned to zero balance within0.3% of the scale capacity;

(2) The charging device cannot be actuated if thedischarge device is open;

(3) The discharge device cannot be actuated if the

charging device is open; and(4) The discharge device cannot be actuated until

the indicated material is within the applicabletolerances.

A tare compensated control is one that treats thestart of the weighing of each ingredient as zero.

For cumulative batchers with tare compensatedcontrols, interlocked sequential controls shall beprovided, and the applicable tolerances shall apply tothe required weight of each individual material.

For cumulative batchers without tare compensated

controls, interlocked sequential controls shall beprovided, and the applicable tolerances shall apply tothe required cumulative weight of material as batched.

2.1.5. Automatic Volumetric Controls for water oradmixtures shall not be furnished with rating plates.When actuated by a single starting signal, automaticvolumetric controls shall start the batching operationand stop automatically when the designated volumehas been reached. The batching control shall includevisual means of observing either the quantity sent orthe quantity batched and the indication of thecompletion of the batching operation.

2.1.6. A Manual Batching System shall consist of therequired combination of individual manual batchercontrols and shall not be furnished with a rating plate.

2.1.7. A Partially Automatic Batching System shallconsist of the required combination of batchingcontrols, at least one of which shall be for controllingthe cement or aggregates, either semi-automatically orautomatically. Inclusion of admixture controls isoptional. This system shall be furnished with a ratingplate. Interlocking in any degree shall be optional.

2.1.8. A Semi-Automatic Batching System shall consist

of the required combination of semi-automaticinterlocked batching controls or of semi-automaticinterlocked and automatic batching controls. Thissystem shall be furnished with a rating plate. Inclusionof admixture controls is optional, unless the admixturebatching is initiated by the act of batching one of theother ingredients. Interlocking in any degree shall beoptional.

2-2 CPMB 100-00 Part 2 Plant Control Systems


13/21

CPMB 100-00 Part 2 Plant Control Systems 2-3

2.1.9. An Automatic Batching System shall consist ofthe required combination of automatic batchingcontrols and be furnished with a rating plate only whenmeeting the following requirements:

2.1.9.1. All batching equipment in the system forbatching ingredients by weight must be activated by asingle starting mechanism. A separate startingmechanism is permitted for volumetric batching of

water and/or admixtures not batched at the time ofweighing.

2.1.9.2. Each automatic batcher must return to zerotolerance, and each volumetric device must reset tostart or signal empty before it may be charged.

2.1.9.3. The discharge of any ingredient in the systemmay not start unless all batching controls have beencleared of the previous batch with scales returning tozero tolerance and volumetric devices resetting to startor signaling empty. The discharge of any scale maystart when all the ingredients weighed on that scalehave been batched.

2.1.9.4. Provisions shall be made for adjusting thesequential discharge of the batchers or measuringdevices and the rate of discharge of materials.

2.2. Batching Recorders, General. A batching recordermay be either graphic or digital as described in thefollowing paragraphs. All batching recorders shallproduce a record of the batch weights or volume ofeach material requiring recordation, a batchidentification or a batch count, day, month, year, timeof day to the nearest minute and shall register emptybalance. Any automatically produced permanentrecord, including the above minimum information,shall be considered an acceptable batching record.Target weights, simulated weights or any other weightsother than actual batch weights shall be clearlyidentified as to their representation.

2.2.1. A Graphic Recorder is an instrument that scribesa line on a graphic chart simultaneously with theindication of the scale as the materials are beingweighed. Each scale may have its own recorder, or aseries of scales may simultaneously record on a singlegraphic chart. The housing shall be capable of beinglocked and the batch weights or volumes observed

without unlocking. The chart for each scale to berecorded shall not be less than 4 inches (100 mm) wideand shall have at least one line for each 2 percent ofscale capacity, but not more than 25 lines per inch (oneline per mm). The graphic record shall correspond tothe reading on the scale within one graduation of therecorder.

2.2.2. A Digital Recorder is an instrument that prints

the weight or volume of a material or materials. Therecording of each material may be done after eachmaterial is properly batched or after the total batch hasbeen properly batched. Each measuring device mayhave its own recorder or a series of measuring devicesmay record on the same tape or ticket. A digitalrecorder shall reproduce the reading of the scale beingrecorded within 0.1% of scale capacity and oneincrement of any volumetric batching device.

2.2.3. A Digital Batch Documentation Recorder shallrecord the required information for each material in thetotal batch, identifying each material used along with a

mix formula identification, the size of the total batch orload in commercial units, and an identification of theproduction facilities. Where certain requiredinformation is unchanged from batch to batch, it maybe preprinted, stamped or written on the record. Theload may be identified by a batch count number, aticket serial number or both. The recorder shall becapable of producing at least two documents. If therecorder is interlocked to an Automatic BatchingSystem as defined in these Standards, a singleindication of all batching devices meeting the zero orempty balance interlocks shall be sufficient.

2.2.4. A Digital Concrete Certification Recorder shallproduce at least two tickets of the batch or load, whichin addition to the information required in thepreceding paragraphs shall include the percent of sandmoisture compensation, identification of the purchaser,his job or project and/or the particular placementlocation of the concrete. Space shall be provided for theidentification of the delivery vehicle (truck number),the drivers signature, the signature of the purchaser orhis representative receiving the concrete and theamount of water added on the job.


14/21

TABLE OF CONTENTS


3.1. Standard Sizes

3.2. Volume Limitations

3.3. Specifications

3.3.1. Size and Mixing Capacity

3.3.2. Computed Interior Volume

3.3.3. Water Level Capacity

3.3.4. Mixing Speed

3.4. Definitions

3.4.1. Concrete Plant Mixer

3.4.2. Non-Tilting Mixer

3.4.3. Tilting Mixer

3.4.4. Vertical Shaft Mixer

3.4.5. Horizontal Shaft Mixer


These standards cover fifteen (15) standard sizes infive (5) types of plant mixers that are eligible to haverating plates attached to them.

Plant mixers eligible to be designated as standardshall conform to the applicable requirements set forthhereafter in these Standards.

3.1. Standard Sizes. The sizes listed in Table 3.1 shall bestandard for each type shown.

3.2. Volume Limitations. The gross volume of a

standard size concrete plant mixer shall conform to theminimum volumes set forth in Table 3.1. The basis forestablishing the minimum volumes for the five mixertypes is provided in Appendix A-1.

3.3. Specifications

3.3.1. Size and Mixing Capacity. The size of a mixershall be its rated maximum mixing capacity. The ratedmaximum mixing capacity as shown in Table 3.1 is themaximum volume of concrete that can be held andmixed properly when the mixer is operated in itsnormal mixing position, based on the slump range andmaximum aggregate size as indicated in Table 3.2.

However, the manufacturer may provide a data plateon the mixer showing the same or a lower capacity, inwhich case such limitations shall govern.

3.3.2. Computed Interior Volume. The computedinterior volume of the mixing compartment shall be notless than the minimum volume prescribed for its sizeand type in Table 3.1.

3.3.3. Water Level Capacity. The water level capacity ofthe mixing compartment (below a horizontal planethrough the lowest edge of the lowest opening that isopen while mixing) when the mixer is operating in itsnormal mixing position shall be not less than 70 percentof the rated maximum mixing capacity prescribed forits size and type in Table 3.1.

3.3.4. Mixing Speed. A data plate indicating mixingspeed in rpm shall be attached to the mixer. The mixingspeed shall be as designated by the manufacturer asbest suited for the maximum rated capacity.

CPMB 100-00 Part 3 Plant Mixer Equipment 3-1

Part 3 - Plant Mixer Equipment


Plant Mixer Manufacturers Division


15/21

3-2 CPMB 100-00 Part 3 Plant Mixer Equipment

3.4. Definitions

3.4.1. Concrete Plant Mixer A machine used tocombine cementitious materials, water, aggregates andother ingredients to produce concrete in a batch, andusually operated in a fixed plant location while mixingconcrete.

3.4.2. Non-Tilting Mixer A rotating drum mixer thatcharges, mixes and discharges with the drum axishorizontal.

3.4.3. Tilting Mixer A rotating drum mixer thatdischarges by tilting the drum about a fixed or movablehorizontal axis at right angles to the drum axis. Thedrum axis may be horizontal or inclined from thehorizontal while charging and mixing.

3.4.4. Vertical Shaft Mixer A mixer with anessentially level floor and cylindrical or annular mixingcompartment, with one or more vertical rotating shaftsto which blades or paddles are attached. The mixingcompartment may be stationary or rotate about avertical axis.

3.4.5. Horizontal Shaft Mixer A mixer with astationary or rotatable cylindrical mixing compartment

with the axis of the cylinder horizontal and one or morerotating horizontal shafts to which mixing blades areattached.


16/21

CPMB 100-00 Part 3 Plant Mixer Equipment 3-3

Single Compartment Two Opening Non-Tilting Type

1 94 (2.7) 0.75 2.62 178 (5.0) 1.5 4.9

312 304 (8.6) 2.5 8.1

412 388 (11.0) 3.5 11.2

One Opening Tilting Type, Mixing Angle of Drum 15with Horizontal

2 153 (4.3) 1.5 4.3

412 288 (8.2) 3.5 8.3

6 369 (10.4) 4.5 10.3

8 477 (13.5) 6 13.3

9 531 (15.0) 7 15.3

10 585 (16.6) 7.5 16.3

12 678 (19.2) 9 18.9

15 798 (22.6) 11.5 22.6

Two Opening Front or Rear Charge and Front Discharge Tilting Type

2 192 (5.4) 1.5 5.3

412 401 (11.4) 3.5 11.5

6 492 (13.9) 4.5 13.8

8 604 (17.1) 6 16.9

9 657 (18.6) 7 18.8

10 708 (20.0) 7.5 19.8

12 806 (22.8) 9 22.5

14 899 (25.5) 10.5 25.1

15 944 (26.7) 11.5 26.8

Vertical Shaft Type12 29 (0.8) 0.375 0.8

1 56 (1.6) 0.75 1.6

112 72 (2.0) 1 1.9

2 87 (2.5) 1.5 2.4

3 118 (3.3) 2 3.0

312 134 (3.8) 2.5 3.6

412 165 (4.7) 3.5 4.7

Horizontal Shaft Type12 13 (0.37) 0.375 0.35

1 29 (0.8) 0.75 0.8

2 60 (1.7) 1.5 1.7

3 92 (2.6) 2.5 2.9

4 124 (3.5) 3 3.5

41

2 153 (4.3) 3.5 4.46 204 (5.8) 4.5 5.7

8 272 (7.7) 6 7.6

9 306 (8.7) 7 8.8

10 340 (9.6) 7.5 9.5

12 408 (11.6) 9 11.3

Table 3.1

Standard Sizes and Minimum Volume in Cubic Feet for 5 Types of Mixers

Size and Maximum Minimum ApproximateMixing Capacity (C), Volume Volume

cu. yd. (V), ft3 (m3)

Nearest Mixer Size and Volume inSI Units

(See CPMB 100M-00)

C, m3 V, m3


17/21

3-4 CPMB 100-00 Part 3 Plant Mixer Equipment

Table 3.2

Concrete Characteristics

MaximumSlump Range, Aggregate Size,

Type Mixer inches (mm) inches (mm)

Single Compartment Two Opening non-Tilting Type 112 - 3 2(38 - 75) (50)

One Opening Tilting Type, Mixing Angle of Drum 15With Horizontal 112 - 3 3

(38 - 75) (75)

Two Opening Front or Rear Charge and Front Discharge Tilting Type 112 - 3 3

(38 - 75) (75)

Vertical Shaft 1 - 4 2

(25 - 100) (50)

Horizontal Shaft 1 - 6 3

(25 - 150) (75)

The use of slumps and aggregate sizes other than those given here may require a capacity less than those

indicated in Table 3.1.


18/21

Part 3 of the Concrete Plant Standards for PlantMixer Equipment establish standard sizes of mixers interms of their rated maximum mixing capacities andthe minimum volumes of drums or troughs requiredfor the different capacities. The relationships betweenrated capacity or drum or trough volumes are based ontests and experience of mixer manufacturers. Therelationships between minimum volume requirements(designated as V) in cubic feet and rated maximummixing capacity (designated as C) in cubic yards areshown below.

1. For single compartment two opening non-tilting

type mixers:V = 84C + 10

2. For one opening tilting type mixers, mixing angle ofdrum 15 with horizontal:

For less than 2 cu. yd. sizes:V = 66C + 20

For 2 through 11 cu. yd. sizes:V = 54C + 45

For sizes larger than 11 cu. yd.:V = 40C + 198

3. For two opening front or rear charge and frontdischarge tilting type mixers:

For 1 through 4 cu. yd. sizes:V = 100(C)0.94

For larger than 4 cu. yd. sizes:V = 138(C)0.71

4. For vertical shaft type mixers:

For 12 cu. yd. size:V = 29

For larger than 12 cu. yd. sizes:V = 31C + 25

5. For horizontal shaft mixers:For 12 through 4 cu. yd. sizes:V = 32C - 3.5

For larger than 4 cu. yd. sizes:V = 34C

Volume computations are made in the followingmanner:

A. Non-Tilting and Tilting Type Mixers (1-3). Volumeis the computed volume of the drum inside liners, ifany. Blades, buckets, or paddles and the arms orbrackets that support them are not deducted. Anypart of the mixer drum at a conical end terminatingin an opening is excluded from the volume beyonda plane where the drum diameter is twenty-fourinches. The volume of cylindrical or conicaldischarge spouts or charging chute extensionsbeyond the main part of the mixer drum is excluded

from the drum volume.

B. Vertical Shaft Type Mixers (4). Volume is computedas the water level volume of the mixer afterdeducting any space occupied by inner housings,heads, spinners, or liners, if any. Blades or paddlesand the arms or brackets that support them are notdeducted.

C. Horizontal Shaft Type Mixers (5). Volume is the netvolume of the mixing compartment below a planeextending horizontally across the top arc of theinside body shell radius; but not higher than thelowest point on the top edge of the body shell; andexcluding the volume occupied by the shafts, liners,paddle or blade arms, and blades, paddles or tips.

CPMB 100-00 Appendix A-1 A-1

APPENDIX A-1Basis for Calculating Minimum Volumes of Concrete Plant Mixers in Accordance with Part 3 of the Concrete PlantStandards of the Concrete Plant Manufacturers Bureau

(See CPMB 100M for sizes in SI sizes)


19/21

From USTo SI (Metric)

MultiplyCustomary Base Unit Symbol by

in. millimeter mm 25.4 (exact)

lb. kilogram kg 0.45359

short ton metric ton,(2000 lb.) (1000 kg) t 0.90718

yd3 cubic meter m3 0.76455

ft3 cubic meter m3 0.028317

Lb/ft3 kg/m3 16.01846

lb/yd3 kg/m3 0.59328

fl. oz. milliliter mL 29.574

fl. oz./100 lb. mL/100 kg 65.198

gallon liter L 3.7854

Gal/yd3 L/m3 4.9511

IEEE/ASTM SI-10 - Standard for Use of the International System ofUnits (SI): The Modern Metric System

A-2 CPMB 100-00 Appendix A-2

APPENDIX A-2Conversion factors from US Customary to SI (Metric) Units

NEED HELP

It is the policy of the Bureau to make its services available to all specifying agencies on problems

involving those specifications allied with concrete plant equipment. Requests for assistance can bemade by contacting any Bureau member or the Executive Secretary of the Bureau at BureauHeadquarters in Silver Spring, Maryland. All problems involving specifications are then directed to theChairman of the Bureau. If immediate action is not required, the Chairman includes the problem on theagenda for the next regularly scheduled Bureau meeting. If the Chairman determines that immediateaction is required, he designates two or more representatives from member companies to act on behalfof the Bureau and notifies all other member companies. Each member has the right to send onerepresentative to meetings and conferences.

OTHER CPMB PUBLICATIONS

Publication No. CPMB 100M-00 Concrete Plant Standards (Metric Version)

Publication No. CPMB-101 Bin or Silo Capacity Rating and Method of Computation

Publication No. CPMB-102 Recommended Guide Specifications for BatchingEquipment and Control Systems in Concrete Batch Plants


20/21

NRMCA endorses the members of the ConcretePlant Manufacturers Bureau as the preferredprovider of concrete plants and associatedequipment as providing quality equipmentconforming to the standards and specifications ofNRMCAs plant certification program and the

concrete plant manufacturers standards.


21/21

Concrete Plant Manufacturers BureauMember Companies

Concrete Plant Manufacturers Bureau900 Spring Street Silver Spring, MD 20910 301-587-1400 Fax 301-587-1605

www.cpmb.org

concrete plant standards

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