Conveyor Equipment Manufacturers Association · Check existing calcs and compare for multiple load points. #2 is out of discussion – dropped. ... The status of the ABNT Portuguese

THE VOICE OF THE NORTH AMERICAN CONVEYOR INDUSTRY

AGENDA OF THE CEMA ENGINEERING CONFERENCE

BULK BELT SYSTEMS AND EMERGING TECHNOLOGIES COMMITTEE

Tuesday, June 27, 2017 – 2:00 P.M.

1. Call to Order – Paul Ormsbee, Vice Chair 2. Attendance and Introductions 3. Review of Last Meeting Minutes (Attached) 4. Old Business

Update of book publications (English, Spanish, Portuguese)

YTD Book sales – including Spanish and Portuguese.

Current and new Errata to the current publication. 6. New Business

Belt Mistracking Allowances

Todd Swinderman to lead discussions. Ref: Appendix D in Belt Conveyors for Bulk Materials 7th Edition

7. Next Meeting – June 26, 2018, La Playa Hotel, Naples 8. Adjourn

Background from T. Swinderman on Item 6

I would like to discuss Appendix D in Belt Conveyors for Bulk Materials 7th edition at the upcoming Engineering Conference. Probably either in the Emerging Technologies Committee and/or the General Bulk Section meeting.

What I have been looking at arises from questions I get from engineering firms and end users about the design allowance for mistracking and on belt tracking procedures I get during my Foundations seminars.

When I started to look into the issue I find lots of variation in installation tolerances for conveyor structures. There doesn't seem to be many standards covering this issue. I have found some industry and company specifications. The basic issue is with CEMA's Appendix D using a fixed dimensional allowance for alignment regardless of belt width where other sources use a dimensional allowance that varies with belt or pulley face width.

Conveyor Equipment Manufacturers Association

THE VOICE OF THE NORTH AMERICAN CONVEYOR INDUSTRY

Another issue is the way CEMA Appendix D defines measuring idlers for alignment where a fixed dimension is given for diagonal measurements "across two sections" without regard to belt width. Not sure what "two sections" are but if I assume 20 ft sections, which are common, the +/- 1/8 inch in 40 ft on the diagonal is, in my opinion, way beyond what can be reliably measured in the field. Also, I have found alternate methods of measuring squareness that could be discussed.

If either of the chairs is interested in bringing up these topics I can prepare a short summary of the issues I am finding.

1) Appropriate belt mistracking allowances for main pulleys, chutes and structure.

2) Appendix D tolerances and measurement methods

THE VOICE OF THE CONVEYOR INDUSTRY OF THE AMERICAS

MINUTES OF THE CEMA ENGINEERING CONFERENCE

BULK BELT SYSTEMS AND EMERGING TECHNOLOGIES COMMITTEE MEETING

LaPlaya Beach Resort, Naples, Florida Tuesday, June 21, 2016

Called to order. Andrew Hustrulid Chair, Paul Ormsbee ‐ Vice Chair (Mark Wilbur substituted) Agenda approved Prior Meeting Minutes approved. Book Sales

Portuguese CEMA book – Only 8 copies sold.

Spanish version available at the end of July. 2 copies sold.

Participants ‐ try to alert customers in countries about the available book.

Errata on website in English, Spanish and Portuguese.

Review of Open Projects List for Committee (Ref. New Business of June 23, 2015 Meeting Minutes)

Topic Comments

1 Ceramic Pulley Lagging Form a subcommittee

2 Recent changes to ASME B20 on guarding of pipe or tube type conveyors idlers nip points.

Guard nip points on ldlers… refer to Safety Committee (in draft safety document provided by SC)

3 Issues related to high speed high capacity conveying Idler Committee working on this

4 Skirtboard sealing strips. Page 39. Only a generic version is shown. Should we show different styles and comment on advantages/disadvantages? Recommend Accessory Committee to review but not in time for belt book.

Accessories working on this

5 Conveyor Belt Scale Applications Need more input…

6 There was a desire expressed to add calculations for pull out tension when there are multiple load points on a belt that may all be plugged.

Need more input…

7 Required: Better methods to determine minimum pulley diameters to transmit a given horsepower.

Form a subcommittee

8 Suggested: Use established ISO standards rather than reinventing them regarding safety and use of guarding.

Safety

9 Fibril Idler rolls used for lightweight wide belt applications Idler Committee



10 U‐ Shaped idlers Idler Committee

11 5 Roll idlers Idler Committee is working on this

12 Investigate: CEMA inclusion for cleated belting for inclines greater than 18° slope. In other countries there are belts running at 22° slopes.

13 Investigate: Belt technology outpacing component design regarding material impact loading and speed capabilities – what’s being done.

14 Required: Method to determine horsepower requirements due to having plugged chutes. This is like a feeder application that causes shear loading drawing material from the chute.

15 Required: Add scales as an accessory. The effects of its use regarding cost and accuracy. Phil stated that it is addressed in Handbook 44.

NIST Handbook 44 Section 2.21.

16 Energy efficiency scale. Standardized design of system and components based on energy efficiency. European tires have a scale that indicated energy efficiency. Come up with a scale that falls into seven (7) divisions that are easily understood to indicate energy efficiency of conveyors based on friction factor.May have a cold region and hot region version to account for variations in climate. Expand to maintenance and clean up.

17 Expand on gearless conveyor drives.

“Ceramic Lagging” sub committee (ref. #1 and #7)

The question posed is how does the pulley diameter influence the amount of power that can be transmitted.

Is increasingly relevant with high tension steel cord, gearless drive systems, and ceramic pulley lagging.

Committee members: Paul Ormsbee, Judd Rossenberry, Andrew Hustrulid, Brett Devries, Robin Steven, Harold Dibben, Benjamin Brewer, Gerhard Schmidt, Tim Wolf

“Pull Out Force” sub committee (ref. #6 and #14)

New sub‐committee for pull out force for next belt book: Luis Estay, Mark Wilbur, Paul Ormsbee, Todd Hollingworth.

Presentation and calculation method from Mark Wilbur of OCC attached.

1‐2 pages in belt book written and described for meeting.

Check existing calcs and compare for multiple load points. #2 is out of discussion – dropped. #3 High speed conveying ‐ idler committee #4 Skirtboard sealing strips ‐ accessories committee #5 dropped because same as #15 #8 safety committee – no further action #9 & #11 5 roll idlers ‐ idler committee #10 u shaped idlers ‐ idler committee


#12, #13, #15‐ #17 new for CEMA 8th edition – ongoing ideas. New Business

Request for more data on skirtboard friction for different materials. ‐> Accessory committee to add skirt board friction factors.

Presentation by Andrew Hustrulid on Minimum Pulley Diameters.

Attached.

Questions: face pressure 100 to 150x cord diameter

Opportunity to set standard with work to be done.

Add section for min pulley diameter for cleaning. Next meeting June 27, 2017, Naples, FL Adjourn


MINUTES OF THE CEMA ENGINEERING CONFERENCE

BULK BELT SYSTEMS AND EMERGING TECHNOLOGIES COMMITTEE

Tuesday, June 23, 2015 – 2:00 P.M.

1. The meeting was called to order at 2:00 PM by David Keech, Vice‐Chair 2. Roll Call – Forty‐four (44) attendees. See attached list. 3. Approval of Agenda ‐ The Agenda was approved. 4. Old Business

Review of the Belt Book 7th edition. a. The process for 7th Edition errata was reviewed and discussed. b. “Belt Book” sales were reviewed and continue to be strong. c. The status of the ABNT Portuguese translation of the “Belt Book” was discussed. The translation is complete and the intended release is for November 2015. d. The status of the Spanish language translation was discussed. The translation is nearly completed and the finished version should be available later this year in a .PDF format, a printed book or possibly both.

5. New Business New Projects that were dicussed: Topic Comments

1 Ceramic Pulley Lagging Form a subcommittee

2 Recent changes to ASME B20 on guarding of pipe or tube type conveyors idlers nip points.

Guard nip points on ldlers… refer to Safety Committee (in draft safety document provided by SC)

3 Issues related to high speed high capacity conveying Idler Committee working on this

4 Skirtboard sealing strips. Page 39. Only a generic version is shown. Should we show different styles and comment on advantages/disadvantages? Recommend Accessory Committee to review but not in time for belt book.

Accessories working on this

5 Conveyor Belt Scale Applications Need more input…

6 There was a desire expressed to add calculations for pull out tension when there are multiple load points on a belt that may all be plugged.

Need more input…

7 Required: Better methods to determine minimum pulley diameters to transmit a given horsepower.

Form a subcommittee

8 Suggested: Use established ISO standards rather than reinventing them regarding safety and use of guarding.

Safety

9 Fibril Idler rolls used for lightweight wide belt applications Idler Committee



10 U‐ Shaped idlers Idler Committee

11 5 Roll idlers Idler Committee is working on this

12 Investigate: CEMA inclusion for cleated belting for inclines greater than 18° slope. In other countries there are belts running at 22° slopes.

13 Investigate: Belt technology outpacing component design regarding material impact loading and speed capabilities – what’s being done.

14 Required: Method to determine horsepower requirements due to having plugged chutes. This is like a feeder application that causes shear loading drawing material from the chute.

15 Required: Add scales as an accessory. The effects of its use regarding cost and accuracy. Phil stated that it is addressed in Handbook 44.

NIST Handbook 44 Section 2.21.

16 Energy efficiency scale. Standardized design of system and components based on energy efficiency. European tires have a scale that indicated energy efficiency. Come up with a scale that falls into seven (7) divisions that are easily understood to indicate energy efficiency of conveyors based on friction factor.May have a cold region and hot region version to account for variations in climate. Expand to maintenance and clean up.

17 Expand on gearless conveyor drives.

Presentation on Lagging Friction – Brett DeVries. There was a lot of very good discussion during the presentation.

Identification of Working Groups and Volunteers. There was interest in forming a sub‐committee to investigate items 1 and 7 from the above list and they will be combined into one working Group. Andrew Hustrulid, Brett DeVries, Robin Steven, Harold Dibben, Benjamin Brewer, Gerhard Schmidt and Tim Wolf volunteered to be on the sub‐committee.

6. Election of Chair and Vice Chair

Andrew Hustrulid – Shaw Almex Industries is the Chair Paul Ormsbee – Overland Conveyor Co. is the Vice‐Chair

7. NEXT MEETING – June 21, 2016, LaPlaya, Naples 8. Adjourned at 3:20 PM

Plugged chute calculation - per BHP Bruff's method - to be applied as calculator within BAUser Inputs:

≔l 6 ft effective length under the chute - No easy default... needs to be user input≔bav 2 ft effective width under the chute - User can change, but we can default this to 2/3 of the belt width

≔ρ 128 ――lb

ft3

material density (power density) - Already a BA input, so we can default to whatever has already been input in BA≔x 2 1 for flow conditions, 2 for starting - Can make this a radio button on the form, i think

Fixed Values for calculation:≔f 0.4 friction factor

Calculation:≔PullOutForce =⋅⋅⋅⋅⋅⋅x 2 l bav

2ρ f g ⎛⎝ ⋅4.915 10

3 ⎞⎠ lbf

Pull out force is the output. This all should be put onto a form similar to the already existing belt speed calculator within BA

SELECTING PULLEY DIAMETERS

FOR CONVEYORS

ANDREW HUSTRULID JUNE 21, 2016

• Reasons to choose a smaller pulley diameter

• Requires less space

• most likely lighter and less expensive

• smaller gear box for a drive, less torque for a brake

• Reasons to choose a larger pulley diameter

• Better possibility for “Flexible” pulley design.

• Easier to clean the belt.

• No matter what - don’t want to hurt the belt / splice.

“IDEAS” BEHIND MINIMUM PULLEY DIAMETERS

• For Fabric Belt

• Keep the outer ply / surface of the carcass below some % of rated tension.

• Keep the inner ply / surface out of compression.

• For Steel Cord Belt

• Pressure under cord

• 100 x cord diameter

• Math from Ideas and Tables not in agreement. A lot based on experience.

INDUSTRY STANDARDS

• ISO 3684: 1990 Conveyor belts - Determination of minimum pulley diameters

• DIN 22101:2002-08 Continuous Conveyors - Belt Conveyors for Loose Bulk Materials - Basis for Calculation and Dimensioning, Chapter 11

• CEMA 7th Edition Table 7.39 - 7.42 Typical Ratings for multi-ply conveyor belting

• CEMA Standard B105.1 - 2015 Table 1 Maximum Belt Tension

ISO 3684: 1990 CONVEYOR BELTS - DETERMINATION OF MINIMUM PULLEY DIAMETERS

• Committee work started in 1968. Took until 1976 to reach consensus.

• Published 1976. *Steel cord added in 1990. Minor amendment 2006.

• Minimum pulley diameter:

D = e x C

e = carcass thickness

C = carcass factor

Name C

Nylon 90

Polyester 108

Steel Cord* 145


• Standard Pulley Sizes - 100, 125, 160, 200, 250, 315, 400, 500, 630, 800, 1000, 1250, (1400), 1600, (1800), 2000, (2240), 2500

• RMBT - Recommended maximum belt tension

• over 60% up to 100% of - standard pulley diameter

• over 30% up to 60% of RMBT - One step lower in R10 series

• up to 30% of RMBT - Two steps lower in the R10 series

Additional “Reductions”

• Group A - no additional reductions

• Group B - return pulleys in low belt tension zones - One steps lower in R10 series.

• Group C - snub pulleys ( < 30 deg wrap) - Two steps lower in R10 series.

But……

• No B pulley smaller than 2 steps down and No C pulley more than 3 steps down.

MINIMUM DIAMETER TABLE



Minimum pulley diameters are dependent on

• Carcass material

• Carcass thickness

• Maximum tension in system as % of belt operating rating (RMBT)

• Pulley type - High tension, low tension, snub.

• DIN 22101:2002-08 Continuous Conveyors - Belt Conveyors for Loose Bulk Materials - Basis for Calculation and Dimensioning, Chapter 11

• Very similar to ISO 3684

• Last approved 2002

• In ISO 3684 RMBT is not defined mathematically. In DIN they set this as 1/8 of the breaking strength. i.e. an 8:1 safety factory. So for some belts, i.e. steel cord, you can have a RMBT greater than 100%.


• Table from the ARPM - North American belt manufactures - Contitech and Fenner.

• Possible, and likely, the manufactures allow even smaller pulleys than what is published in CEMA

• This methodology is how I have been taught to size pulleys over the last 20+ years - Overland Conveyor, Scandura, Georgia Duck, Fenner, NIBA.


ISO 3684 CEMA

Carcass material Carcass construction w/ material

Carcass Thickness Carcass construction w/ material

Maximum tension in system Belt tension at specific pulley

Pulley Type ** Allowance for steel cord snub pulleys.

Personally like the CEMA methodology better.

0

6

12

18

24

30

36

42

0 100 200 300 400 500 600 700 800 900

Minim

umPulleyDiam

eter(in)

BeltRa3ng(PIW)

CEMABelt

ISO3684

FLEXCO MECHANICAL FASTENERS

B105.1 TABLE

• MPTA / CEMA has published these pulley ratings since 1960.

• Only organization globally that I am aware of that publishes pulley ratings.

0

6

12

18

24

30

36

42

48

54

60

66

0 200 400 600 800 1000 1200

PulleyDiam

eter(in)

MaximumBeltTension(PIW)

B105.1180deg

B105.160deg

CEMA PULLEY RATING WRT WRAP ANGLE

-

0.20

0.40

0.60

0.80

1.00

1.20

0 30 60 90 120 150 180 210 240 270WrapAngle(deg)

CEMAPulleyRa5ngwrtWrapAngle

8

10

12

14

16

18

20

24

30

36

42

48

54

60

DIFFERENT SHELL WRAP ANGLE PARAMETER

0

6

12

18

24

30

36

42

48

54

60

66

0 200 400 600 800 1000 1200

Minim

umPulleyDiam

eter(in)

BeltRa3ng(PIW)

CEMABelt

ISO3684

B105.1180deg

B105.160deg

Documents

Conveyor Equipment Manufacturers Association · Check existing calcs and compare for multiple load points. #2 is out of discussion – dropped. ... The status of the ABNT Portuguese