FUNDAMENTALS OF
CONVEYOR SYSTEMS
Presented by:
Laura Hoggan, Rubber & Plastics
Topics to be Covered
 System Maintenance
 Belt Maintenance
 Anatomy of a belt
 Common Frac Sand belt specifications and designs
Section I: System Maintenance
System Square
 A conveyor system frame is like a car frame, if your frame is not
square it will throw off other components, creating wear and tear.
 The Dragon Tail is the most susceptible area for being out of square,
check it often!
Cleaning
• Good system maintenance can be summed up in two
words, “Good Housekeeping”.
• Check pulleys and rollers for material build-up.
Loading Area
 Having the right equipment
and a good transaction area is
a key component in system
life and belt life.
 Bad Loading can result in:
 Catastrophic failure
 Damage to belt
 Tracking issues
TO-DO LIST!
 Follow OEM guide for lubrication
schedule
 Visually inspect:
 Rollers, Pulleys, Return rollers & belt
guides for excessive wear, built up
material and damage.
 Belt Splice for wear on lace, cracks,
missing components.
 Sidewall for damage and missing sections
 Inspect belts:
 Tracking properly
 Tension
Section II: Belt Maintenance
Belt Tracking/Training Considerations
 Conveyor belt moves toward the end of the roller/idler it contacts first
 Check conveyor system for structural misalignments
 Check pulleys and idlers for misalignment and material build-up
 Check belt splice for accuracy and straightness
 Observe belt in operation empty and loaded for tracking tendencies
 Eliminate Spillage, Off-center loading and build-up of materials, factors that
cause tracking issues
Splice Failures
 Inspect lace to ensure all parts are still present
 Inspect Vulcanized splices for cracking, splitting and loose sidewall sections
Belt Repair
 Flexco® offers a variety of rip
repair fasteners. With these you
can patch soft spots before they
become rips or a cut or tear in
your belt to extend your belt life
 Eli-Flex rubber repair kits for
holes, tears, splits, gouges and
excess wear areas
 SuperScrew patch kits for holes
and tears. Provides water tight
What happens if I install the wrong belt spec?
 Belt will wear faster than expected
 Belt may potentially fail
 Cleats and/or Sidewall may separate
from belt
Section III: Anatomy of a belt
Belt Specification Breakdown
3 = Number of Tension Plies
2 = Number of Cross Rigid
Plies
What is a Ply?
 A rubber coated layer of fabric
 Each “fabric” layer is a ply
 Commonly a Polyester/Nylon
material
 Are the strength member of the belt
How do you know how many plies you have?
 Count the number of layers of fabric visible in the belt
CROSS RIGID BELT
 Engineered for applications that
take a sharp upturn, with a heavy
cleat and/or corrugated sidewall.
 Cross Rigid belts are rigid across
the belt (fill or weft direction)
 Provides lateral reinforcement that
keeps the belting rigid
 Cross Rigid belting will withstand
deflection from horizontal to
incline without bowing or sagging
during operations.
Belt Specification Breakdown
 3 = Number of Tension Plies
 2 = Number of Cross Rigid Plies
 330 = Working tension per inch width
Working Tension
 Working tension is a factor of the fabric/ply
 Rated on a per inch width
 Fabric strength has a direct impact on minimum pulley diameter
requirements
Why does it matter?
 Belt can snap in operation if not rated for the tension of the system
Belt Specification Breakdown
 3 = Number of Tension Plies
 2 = Number of Cross Rigid Plies
 330 = Working tension per inch width
 1/8 = Thickness of Rubber top cover
Top Cover Thickness
 Provides an impact and abrasion resistance layer, protecting the belt fabric
 There are standard cover thicknesses which vary based on the plies and
tension rating of the belt
 Custom thicknesses are available but usually require a minimum quantity
purchase
Belt Specification Breakdown
 3 = Number of Tension Plies
 2 = Number of Cross Rigid Plies
 330 = Working tension per inch width
 1/8 = Thickness of Rubber top cover
 1/16 = Thickness of Rubber bottom cover
Bottom Cover of a Conveyor Belt
 May have a rubber bottom or a “bare-back” bottom
 PVC belts are:
 COS = Cover one Side
 CBS = Cover both sides
 Rubber Belts are:
 Called out by actual thickness of cover materials
What is a “Bare-Back”?
 A conveyor belt with no bottom rubber cover
 Bottom of conveyor belt is the fabric from the bottom ply
Why use a “Bare-Back”?
 Slider Bed Applications
 Fabric bottom has a lower coefficient of friction than a Rubber bottom
Belt Specification Breakdown
 3 = Number of Tension Plies
 2 = Number of Cross Rigid Plies
 330 = Working tension per inch width
 1/8 = Thickness of Rubber top cover
 1/16 = Thickness of Rubber bottom cover
 MOR / Grd II = The type of Rubber Material used in
the belt
What Rubber Compounds are common?
RMA GRADE 2
MOST COMMON
COMPOUND
GREAT FOR ALL
GENERAL MATERIALS
AND PRODUCTS
GOOD IMPACT AND
ABRASION RESISTANCE
RMA GRADE 1
MAINLY FOR HIGH
IMPACT, CUTTING AND
ABRASION
APPLICATIONS
MORE NATURAL
RUBBER
BEST IMPACT,
ABRASION AND GOUGE
RESISTANCE
MOR
MAINLY FOR ANY
APPLICATION WHERE
OILS WILL BE PRESENT.
IS MODERATELY
RESISTANT TO OILS
AND SOLVENTS
Section IV: Common Belt Specifications and
Designs in Fracking
Profile Belts
 Why use a profile belt?
 Inclines greater than 20°
 To prevent roll back of material
 Common Profiles
 Herringbone
 Chevron
 V-Cleat
 MaxClimb
 MegaClimb
Frac Sand Belt Configurations
Sidewall Belt; No cleats 
Typically on Sand Delivery Units

Sand Delivery Units receive sand
transported to the well site.

Uses a combination of hoppers and
conveyor belts to move frac sand to the
T-Belt during fracking operations.

Operates on Troughing Idlers
Details:

Sidewall height
from 2” to 4”

Available on any
belt specification
Frac Sand Belt Configurations
Narrow Width MaxClimb w/ Sidewall
 Typically on the T-Belt (Dual Belt Units)
 Takes discharge from multiple Sand
Delivery Units and delivers to the
blenders.
 Compartmented belt allows for high
angle discharge of materials.
Details:
 30” and Narrower belts
 1-1/4” tall cleats
 Sidewall heights of 2” to 6”
Frac Sand Belt Configurations
MaxClimb w/ Sidewall
 Typically on the T-Belt (Single Belt Units)
 Takes discharge from multiple Sand
Delivery Units and delivers to the
blenders.
 Compartmented belt allows for high
angle discharge of materials.
Details:
 30” and Wider belts
 1-1/4” tall cleats
 Sidewall heights of 2” to 6”
Frac Sand Belt Configurations
3” Peg Belt w/ Sidewall
 “Peg” or “Finger” Belt
 Conveys continuous flow of material
 Powder to moderate lump sizes
 Up to 45° Angles
 High material capacity
 Can be on Delivery Units or T-Belt
Units
Details:
 24” or 30” Wide (Peg pattern is 20”)
 Available on any belt specification
 Pegs are 70 durometer
Belt End Preparation
Super Screw
Hot Vulcanized
 Provides 5x greater adhesion than
chemical bonds
 Prevents product spillage through
the splice
Mechanical Splice
 Installed in Factory, no tools
needed in field
Frack Sand can corrode and wear
down metal fasteners that are not
protected with a rubber cover.
Inspect often to prevent failure!

Mechanically fastened to belt

Can be installed on one end to
expedite field installation

Reduces the installation time and
tools required
How do I know what belt to use?
 Belt selection is based on;
 Minimum pulley diameter
 The configuration of the conveyor system including;
 Type & Style of return
 Incline
 Changes in incline
 Slider bed or troughed rollers
 Overall length
 Height of incline
 Weight of material
Can I change Styles of Frac Belts?
 For the most part, Yes.
 Ensure new belt configuration fits the system, checking the following:
 Sidewall Height
 Cleat clearances (recess, height, etc.)
 Belt configuration may alter the speed at which a belt operates to deliver
the same tonnage per minute.
Frac Sand Environmental Concerns
• Small Pulley Diameters
•
Small pulley diameters put chemical bonds under stress, causing pre-mature failure
• Extreme Environments
•
Extreme cold in South Dakota, Pennsylvania, Canadian markets
•
Cold temperatures degrade the chemical bond, causing pre-mature failure
•
Hot vulcanized sidewall is lasting 5x longer than Chemical bonds
• Field Location Difficulties
•
Timeliness to get to breakdown area
•
Exposure to environment
•
Potential lack of equipment / power sources
How to determine quality of a belt
 Import vs. Domestic
 Location of manufacturing doesn’t matter, the quality does.
 Safety Factors
 Ply Adhesion
 Elongation
 Quality of Value-Add Process;
 Key term: Hot Vulcanization