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JUJUMI SYNCLINE CONVEYOR HANDBOOK

UPDATE 2026

Handbook Index

Foreword

This “CONVEYOR HANDBOOK” is provided by JUJUMI SYNCLINE to allow designers to select the correct specification belting for any particular installation.

Properties of fabrics used in Polyester Nylon multi-ply belting constructions are given in detail, while the general properties and application areas of special multi-ply constructions are also shown. Solid woven and steel cord belting are described in detail in separate sections.

The use of various natural and synthetic rubbers with these reinforcements for handling different service conditions is set out for the designer. Design considerations affecting power demands, belt curves, transitions etc., are provided.

The layout of this manual and its easy approach to belt design will be readily followed by belt design engineers. Should problems arise, the services of JUJUMI SYNCLINE are always available to help with any problems in the design, application or operation of conveyor belts.

1. Materials of Construction

The composition of a conveyor belt can be considered in two parts:

  1. The Carcass: whether ply type (textile) or steel cord construction, which must have sufficient strength to handle the operating tensions and to support the load.
  2. The Covers: which must have the required physical properties and chemical resistance to protect the carcass and give the conveyor belt an economical life span.

Reinforcement Fabrics

The fabric designation indicates the material used in both warp and weft, e.g. PN signifies that the fabric has Polyester warp fibres and Nylon weft fibres. The ultimate strength of the belt in kilonewtons per metre width is shown along with the number of plies. PN1000/4 designates a belt with four plies of polyester warp, nylon weft fabric and an ultimate full-belt tensile strength of 1000kN/m.

CARCASS TYPE CARCASS MATERIALS STRENGTH RANGE (kN/m width) FEATURES AND APPLICATIONS
WARP (longitudinal) WEFT (transverse)
PN plain weave (DIN code EP) Polyester Nylon 315 to 2000 kN/m (150 to 400 kN/m/ply) Low elongation. Very good impact resistance. Good fastener holding. An excellent general purpose fabric.
PN crow's foot weave Polyester Nylon 630 to 2500 kN/m (315 to 500 kN/m/ply) Low elongation. Good impact resistance. Very good fastener holding. Excellent rip resistance. For high abuse installations
PN double weave Polyester Nylon 900 & 1350 kN/m (450 kN/m/ply) Low elongation. Excellent impact resistance. Excellent fastener holding. For high abuse installations.
NN Plain weave Nylon Nylon Up to 2000 kN/m (150 to 450 kN/m/ply) High elongation, mostly replaced by polyester-nylon. Used in special applications where low modulus needed or in high pH environment
ST Steel cord Steel cord None (special reinforcement available) 500 to 7000 kN/m Very low elongation and high strength. Used for long haul and high-tension applications.
SW Solid woven Nylon/cotton or Polyester/cotton Nylon/cotton 600 to 1800kN/m Main use in underground coal mining. Good fastener holding and impact resistance. Used for bucket elevators.

General Properties of Belt Covers and Grades

Conveyor belt covers are classified by application scenarios, including general service, heat resistant, oil & chemical resistant, fire resistant & anti-static types. Special compounding can result in substantial changes to these general polymer properties.

General Service Grades (Mining, Quarrying)

JUJUMI SYNCLINE GRADE Grade M, Grade N Super M MA Grade A (SAR) XCG QuarryMaster
GENERIC TYPE Natural rubber (NR) Natural rubber (NR) Natural Rubber Polybutadiene (NR / BR) Natural Rubber Styrene Butadiene (NR / SBR) Natural Rubber (NR)
APPLICATION Medium to heavy duty mining and quarrying Heavy to extreme mining service with lumps & abrasion Abrasion resistant for fine materials Cut and gouge resistant for heavy service Medium to heavy duty mining and quarrying
SERVICE TEMP RANGE (°C) -30 to 70 -30 to 70 -30 to 70 -30 to 70 -30 to 70
ABRASION RESISTANCE GOOD / VERY GOOD VERY GOOD / EXCELLENT EXCELLENT VERY GOOD GOOD / VERY GOOD

Heat Resistant Grades

JUJUMI SYNCLINE GRADE CRHR Apex EPT-GP EPT-Super HRNR Hi Temp Nitrile
GENERIC TYPE Styrene Butadiene (SBR) Ethylene Propylene Terpoymer (EPT) Ethylene Propylene Terpolymer (EPT) Natural rubber (NR) Nitrile rubber (NBR)
SERVICE TEMP RANGE (°C) -10 to 125 -20 to 170 -20 to 210 -20 to 100 -10 to 125
APPLICATION Heat resistant for lumpy and abrasive materials Heat resistant for fine materials. Resists hardening and cracking Maximum heat resistance for fine materials. Resists hardening and cracking Medium heat resistance. Resists hardening and cracking Oil and heat resistant

2. Belt Capacities

Belt capacity is dependent upon these inter-related factors: Belt width, Belt speed, Material bulk density and surcharge angle, Inclination angle, Troughing angle, Idler configuration.

For maximum haulage efficiency, conveyors should be operated fully loaded at maximum recommended speed.

Capacity Calculation Formula

\[ Capacity\ (tonnes\ per\ hour) = 3.6 × Load\ Cross\ Section\ Area\ (m^{2}) × Belt\ Speed\ (m/s) × Material\ Density\ (kg/m^{3}) \]

For common 3 equal roll trough idlers (35° trough angle, 20° surcharge angle, 1000 kg/m³ density), capacity can be quickly calculated by:

\[ Capacity = Table\ 3\ Value × Material\ Density × Capacity\ Factor × Belt\ Speed / 1000 \]

Capacity Factor (3 Equal Roll Trough Idlers)

Surcharge angle Idler troughing angle
25° 30° 35° 45°
10° 0.70 0.77 0.84 0.94
15° 0.78 0.86 0.92 1.04
20° 0.87 0.94 1.00 1.08
25° 0.96 1.03 1.08 1.15

Standard Capacity Reference (35° Trough, 20° Surcharge, 1000 kg/m³)

Belt width (mm) Belt speed (metres per second)
1 1.5 2 2.5 3 4
500 87 131 175 218 262 349
650 157 235 314 392 471 628
800 247 370 493 617 740 987
1000 398 597 795 994 1193 1591
1200 585 877 1169 1462 1754 2339

Maximum Recommended Lump Size

Belt width (mm) Uniform lumps (mm) Mixed with approx. 80% fines (mm)
500 100 175
650 125 250
800 150 300
1000 200 375
1200 300 450

Maximum Slope Angles

Material Maximum slope angle
Bituminous coal - ROM 18°
Cement, Portland - loose 20°
Earth - loose and dry 18-20°
Grains 15°
Ores - mixed lumps and fines 18°
Sand - damp 18-20°
Wood chips 23-25°

3. Belt Power and Tensions

Power Calculation Formula

\[ Power\ (kW) = \frac{F_{C}\left(L+t_{f}\right)(C+3.6 QS)}{367} \pm \frac{CH}{367} \]

Where:

  • \(F_C\): Equipment friction factor (0.0225 for horizontal/inclined conveyors, 0.0135 for decline regenerative systems)
  • \(L\): Horizontal centre to centre distance (m)
  • \(t_f\): Terminal friction constant (m)
  • \(C\): Capacity (t/h)
  • \(Q\): Mass of moving parts (kg/m)
  • \(S\): Belt speed (m/s)
  • \(H\): Nett change in elevation (m)

Effective Tension & Slack Side Tension

\[ Power = T_e × S\ (kW) \] \[ T_2 = T_e × K\ (kN) \] \[ T_{max} = T_e + T_2\ (kN) \]

Where \(K\) is the drive factor, dependent on pulley surface, arc of contact and tensioning method.

Standard Drive Factor "K" Values

ARC OF CONTACT (Degrees) COUNTERWEIGHT TAKEUP SCREW TAKE-UP
Bare pulley μ=0.30 Lagged pulley μ=0.35 Bare pulley Lagged pulley
180 0.64 0.50 0.97 0.90
210 0.50 0.38 0.80 0.66
240 0.40 0.30 0.68 0.56
360 (Tandem) 0.18 0.13 0.42 0.36

Idler Spacing Recommendations

Belt width (mm) Material density (kg/m³)
800 1200 1600 2000 2400
500 1.7 1.7 1.5 1.5 -
650 1.5 1.5 1.4 1.3 1.0
800 1.5 1.5 1.4 1.2 1.0
1000 1.5 1.4 1.2 1.0 1.0
1200 1.5 1.4 1.0 0.9 0.8

Note: Return idler spacing = approximately 3.0 metres. Impact idler spacing = approximately 1/4 to 1/2 carrying idler spacing. Convex curve idler spacing - at most 1/2 carrying and return idler spacing.

4. Belt Carcass Selection

To select the optimum plied belt carcass, five properties must be considered: Belt width, Service conditions, Maximum operating tension, Minimum number of plies for load support, Maximum number of plies for troughability.

Selection Procedure

  1. Calculate working tension needed for both steady state and peak (accelerating or braking):
    \[ Required\ Working\ Tension\ (kN/m) = \frac{T_{max}\ (kN)}{Belt\ width\ (m)} \]
  2. Determine suitable belt constructions based on operating conditions.
  3. Check load support requirements for the material bulk density.
  4. Verify troughability for the selected trough angle and belt width.
  5. Confirm adequate pulley diameters for the selected carcass.

Safety Factor & Operating Conditions

  • Base safety factor: 6.7:1 on splice strength.
  • Moderate severe conditions: Reduce allowable working tension by 15%, peak tension limit 150% of rated tension.
  • Severe service conditions: Reduce allowable working tension by 30%, peak tension limit 160% of rated tension.

Allowable Working Tension (Standard PN Plain Weave)

Carcass Type Number of plies
2 3 4 5 6
PN 200-220 (Spliced) 30 kN/m 63 kN/m 90 kN/m 120 kN/m 150 kN/m
PN 250 (Spliced) 37 kN/m 75 kN/m 112 kN/m 150 kN/m 187 kN/m
PN 300-315 (Spliced) 48 kN/m 90 kN/m 140 kN/m 180 kN/m 225 kN/m

5. Cover Gauges and Qualities

Key Selection Factors

  • Fire resistance/anti-static requirements
  • Oil/chemical resistance
  • Operating temperature
  • Material abrasiveness, lump size, fall height
  • Conveyor cycle time
  • Previous service experience

Pulley Side Cover Guidelines

  • Not less than 1/4 of carry side cover for covers up to 9mm
  • About 1/3 of carry cover thickness for covers heavier than 9mm
  • Up to 1/2 of carry side cover for long centre, long time cycle conveyors

Top Cover Thickness Selection Guide

Abrasion Level Typical Materials Cycle Time < 30s Cycle Time 30-120s Cycle Time > 180s
Lightly abrasive Wood chips, coal, grains, river gravel 3-5 mm 2-4 mm 1-3 mm
Moderately abrasive Basalt, sand, anthracite, crushed gravel 5-8 mm 4-6 mm 2-5 mm
Heavily abrasive Limestone, ores, phosphate, slag, cement clinker 8-12 mm 6-10 mm 4-8 mm
Extremely abrasive Glass cullet, granite, quartz ores 12-18 mm 10-15 mm 8-12 mm

6. Pulley Diameters

Minimum pulley diameter depends on: Carcass thickness, Operating tension relative to allowable working tension, Carcass modulus.

Pulley types defined in ISO 3684:

  • Type A: High tension / tight side pulleys (head, drive, tripper pulleys)
  • Type B: Low tension / slack side pulleys (tail, take-up pulleys)
  • Type C: Low tension snub/bend pulleys (wrap angle < 30°)

Parallel Face vs Crown Face Pulleys

  • Parallel face pulleys: Mandatory for steel cord belting, recommended for all modern high modulus fabric belts.
  • Crown face pulleys: Only for bucket elevators, long gravity take-up pulleys, short centre reversing conveyors. NOT for steel cord belting.

Pulley Face Width

Pulley face width must exceed belt width to avoid edge damage. Additional 50mm clearance required for underground mining and long overland conveyors.

Minimum Pulley Diameters (PN Plain Weave, >60% Allowable Tension)

Carcass Type Pulley Type Number of plies
2 3 4 5 6
PN 200-220 Type A 400 mm 450 mm 630 mm 800 mm 900 mm
Type B 315 mm 360 mm 500 mm 630 mm 710 mm
Type C 250 mm 280 mm 400 mm 500 mm 560 mm
PN 250 Type A 450 mm 500 mm 710 mm 900 mm 1120 mm
Type B 360 mm 400 mm 560 mm 710 mm 900 mm
Type C 280 mm 315 mm 450 mm 560 mm 710 mm

7. Design Considerations

Vertical Curves

Concave Vertical Curves (Prevent Belt Lift-off)

\[ R = \frac{Factor × T_i}{B × 9.81 × 10^{-3}}\ (m) \]

Factor range: 1.3~2.5, based on starting control method. Minimum factor 1.8 for decline regenerative conveyors.

Convex Vertical Curves

Radius must be selected to keep belt edge tension within acceptable limits and prevent centre buckling.

Transitions (Terminal Troughing to Pulley)

% of allowable working tension All fabric belts (35° trough) Steel cord belts (35° trough)
Head Pulley (High Tension) Tail Pulley (Low Tension) Head Pulley (High Tension) Tail Pulley (Low Tension)
91-100% 1.6 × Belt Width 3.2 × Belt Width 3.4 × Belt Width 6.8 × Belt Width
76-90% 1.4 × Belt Width 3.0 × Belt Width 2.8 × Belt Width 5.4 × Belt Width
50-75% 1.3 × Belt Width 2.8 × Belt Width 2.6 × Belt Width 5.2 × Belt Width
<50% 1.0 × Belt Width 2.0 × Belt Width 1.8 × Belt Width 3.8 × Belt Width

Take-Up Arrangements

Gravity Take-Up Travel (Fabric Belting)

Centre to centre length (m) NN Belting (% of centre distance) PN/KN/PP Belting (% of centre distance)
Up to 30 4.0% 2.0%
31-60 3.5% 1.7%
61-180 3.4% 1.6%
181-300 3.3% 1.5%
Over 300 3.3% 1.3%

Note: Practical minimum take-up travel should not be less than 1 metre. For steel cord belting, 0.25-0.5% of centre distance is typical.

8. General Data

Belt Mass and Thickness Calculation

  1. Look up carcass mass (kg/m²) and thickness (mm) from standard tables.
  2. Multiply carcass mass by carcass mass factor (based on cover grade).
  3. Calculate cover mass: (top cover + bottom cover thickness) × cover mass factor.
  4. Total belt mass per metre: (carcass mass + cover mass) × belt width (m).
  5. Total belt thickness: carcass thickness + top cover + bottom cover.

Standard PN Plain Weave Carcass Data

Carcass Type Number of plies
2 3 4 5 6
PN 200-220 Mass (kg/m²) 4.4 5.1 6.8 8.5 10.2
PN 200-220 Thickness (mm) 3.3 3.9 5.3 6.8 8.2
PN 250 Mass (kg/m²) 4.4 5.8 7.7 9.6 11.5
PN 250 Thickness (mm) 3.3 4.5 6.1 7.8 9.5

Belt Roll Diameter Calculation

\[ D = \sqrt{d^{2}+(0.001273 × L × G)} \]

Where: D=Overall roll diameter (m), d=Core diameter (m), L=Belt length (m), G=Belt thickness (mm)

Transport Guidelines

Freight Type Maximum Roll Diameter Max Load Weight
Road Tray Trailer 2.75m 20-22 tonne
Road Drop-deck Trailer 3.20m 20 tonne
20ft/40ft Sea Container 2.29m 18.3 tonne

9. Solid Woven Belting

Belt Construction

JUJUMI SYNCLINE solid woven belting consists of three main components:

  1. Textile Solid Woven Carcass (nylon/polyester warp, nylon/cotton weft)
  2. PVC Impregnation (fire retardant, anti-static, moisture/chemical resistant)
  3. Cover Material (PVC or rubber, up to 6mm thickness)

Key Properties

  • Operating temperature range: -15°C to 90°C (special grades down to -40°C)
  • Excellent fastener holding and impact resistance
  • Fire resistant & anti-static, meets AS4606 for underground coal mining
  • Superior troughability for small diameter pulleys

Standard Belt Designations

Belt Designation Minimum warp strength (kN/m) Rated tension (kN/m) Nominal thickness (mm) Min Head Pulley Diameter (mm)
3500 630 63 8.1 400
5000 875 87 9.0 500
6000 1050 105 9.6 630
8000 1400 140 11.3 750
10000 1750 175 13.1 800

10. Steel Cord Belting

Construction

Steel cord belts consist of zinc coated steel cables embedded in a bonding rubber matrix, with top and bottom rubber covers. Used for long haul, high tension applications where fabric belts are unsuitable.

Key Advantages

  • Very low elongation (high elastic modulus)
  • High tensile strength (500 to 7000 kN/m)
  • Excellent splice efficiency
  • Smaller pulley diameters than equivalent strength fabric belts

Standard AS1333 Constructions

Designation (kN/m) Cord Diameter (mm) Min Cover Thickness (mm) Min Type A Pulley Diameter (mm) Belt Thickness (mm)
ST800 3.4 4 500 11.4
ST1000 4.0 4 630 12.0
ST1600 5.5 5 800 15.5
ST2000 6.4 5 1000 16.4
ST2500 7.4 6 1120 19.4
ST3150 8.6 6 1250 20.6
ST4000 9.8 7 1400 23.8

Splicing

Steel cord belts are joined by hot vulcanised splices with overlapped cords. Higher strength belts require multi-step splices:

  • ST500-ST2240: Single step splice
  • ST2500-ST4000: Two step splice
  • ST4500+: Three step splice (custom design)

Belt Protection

  • Transverse reinforcement (woven breakers/transverse cords) to prevent longitudinal ripping
  • EagleEye rip detection and condition monitoring system
  • Low rolling resistance pulley cover compounds (PowerPlus) for reduced power consumption

JUJUMI SYNCLINE CONVEYOR BELTING | Handbook