Celebrating 30 years of Service!

  • SBR compound designed specifically for abrasion resistance and heat resistance up to 300°F (149°C). 
  • Proven to be economical and long lasting.
  • Ideal for conveying coke, steel, slag, cement, salt and fertilizer.

GRT HeatKing Belts utilize an all polyester belt carcass to prevent distortion in high heat applications. Using the proper Heat Resistant compound, they will give trouble free service in high heat applications up to and including 450 F.

HeatKing Belts


FlexKing Elevator

GRT FlexKing Belts for Elevator Service give superior service life in a myriad of applications ranging from grain handling to crushed stone. The fabric design and its inherent strength allow the proper FlexKing Elevator Belt to provide excellent bucket holding ability, flexing strength, and long service life. 

• Superior service life and hazard resistance
• Excellent bucket holding capability, flexing strength, and small pulley flexing capability
• Wide range of configurations: It can be custom-designed and special-ordered


  • Ideal for applications with constant material temperatures over 150°F (66°C).
  • All-synthetic fabrics specially woven from polyester fibers for excellent dimensional stability. There is minimal strength loss or stretch in high temperatures.
  • Highly resistant to chemicals and acids, even in hot environments.
  • Low moisture absorption ensures reliable service in wet applications.
  • Widths available to 60" (1500 mm).
  • A wide range of FLEXKING® carcass types are available


HeatKing® RA (HKRA)

HeatKing® OR (HKOR)

  • High quality nitrile elastomer compound is heat- and oil-resistant to temperatures up to 350°F (177°C).
  • Excellent service for handling hot asphalt paving mix, carbon pitch mixes, and other hot petroleum-based products.

Super HeatKing® BT (HKBT)

  • Top quality heat-resistant chlorobutyl compound.
  • Resists the baking and cracking action of hot materials up to 450°F (232°C).
  • Suited for applications such as salt, ash, carbon black, foundry sand, cement clinker, and calcined lime.

HeatKing® EPDM

  • Provides maximum resistance to hot, abrasive loads. 
  • Recommended for hot fines to 400°F (204°C) or loads of coarse materials to 450°F (232°C).
  • Ideal for clinker, calcined lime, carbon black and foundry sand.

HeatKing® Glass (HKGL)

  • Designed to perform reliably under the most adverse temperature conditions.
  • EPDM cover compound handles temperatures up to 450°F (232°C).
  • Glass carcass gives structural integrity and prevents burn-through or distortion in high temperatures up to 1000°F (538°C).
  • Typical applications include cement, clinker, calcined lime and foundry sand.
Call The Experts
Copyright 2015 Dunrite Rubber & Plastic All Rights Reserved.
Sudbury Branch
200 Fielding Road
Lively, Ontario P3Y 1L6
Phone: (705) 682-3233
Fax: (705) 682-3337
Hamilton Branch
161 Brockley Drive
Hamilton, Ontario L8E 3C4
Phone: (905) 578-6807
Fax: (905) 578-9050
Timmins Branch
28 Hallnor Road
Porcupine, Ontario P0N 1C0
Phone: (705) 235-2003
Fax: (705) 235-4346

Impact Guidelines

The impact resistance, based on inches of freefall, is calculated assuming the use of impact reduction equipment, such as impact idlers. If impact reduction equipment is not used, freefall inches must be reduced by one-half. Ratings are based on 10% lumps and 90% fines which includes material sizes up to 4 inches. 

Optimum loading and material transfer design can lessen the force of impacting lumps on the belt and extend belt life. 

Follow these industry-accepted design practices where applicable:

• Reduce the size or weight of the material.
• Break the fall of lumps with bars, chains, or chutes to reduce impact.
• Design loading system to insure the material is loaded in the same direction as the belt travel.
• Load lumps on a bed of fines to reduce impact.
• Do not load in transition areas.
• Use impact idlers and, if possible, design the loading area to strike the belt between idlers in an open unsupported span.
• Increase the belt cover thickness and use breakers in the cover or an extra ply for increased impact resistance.

GRT TECHFLEX® Impact Resistance

Technical Data
Construction: Straight warp double unit
Material: Polyester and nylon
Tension ratings: 600-1000 PIW*
Applications: Log handling, riprap, ballast, hard rock, heavy ores, etc.
* PIW=per inch of width

GRT TechFlex® II

Technical Data
Construction: Straight warp single unit
Material: All polyester
Tension ratings: 220-440 PIW*
Applications: Log handling, riprap, ballast, hard rock, heavy ores, etc.

GRT TechFlex® I

  • Flexibility in carcass design ensures excellent empty belt troughing.
  • Parallel planes of straight crosswise members give strength and stability to bridge the idler roll gaps under full load.

Superior Troughing & Load Support

  • Straight warp weave stretches less than crimped weave fabrics.
  • Longer belt life.

Low stretch

  • Special weave design with fill yarns above and below warp yarns increases the rip resistance.
  • Planes of straight fibers offer additional resistance to lump impact.

Excellent Rip & Impact Resistance

  • Allows belt to operate over smaller pulleys.
  • Resists flex fatigue, lasts longer.
  • Easier to install in hard-to-access areas.

Extra Flexibility

  • Straight warp yarns in parallel planes with special binder provide extra strength.
  • Strong mechanical and chemical bonding between compound and textile increases strength.
  • Reinforcing eliminates need for multiple plies, resulting in a thinner and more flexible belt.

High-Strength Carcass Construction

  • Straight warp single or dual unit construction provides flexibility and superior rip and impact resistance.
  • Tension ratings are 220, 330 and 440 PIW single unit, and 600, 800 and 1,000 PIW dual unit.
  • Ideal for applications such as log handling, riprap, ballast, hard rock, heavy ores and other difficult conditions.
  • Available as a made-to-order product using Garlock's cover compounds.

Problem Solver Conveyor

GRT TechFlex Belts are especially designed for heavy, highly abusive and demanding applications. They provide long service life and low cost per ton in applications where most plied belts have been proven unsuccessful.

TechFlex Belts

Cover: Grade II rubber (standard)
Carcass: All-polyester
Service: Aggregates, clay, coal, ore, phosphates, sand, salt 
With MOR compound for oil resistance: Wood chips, wood bark, sawdust, whole grains
  • Available in two, three, and four-ply construction with covers of RMA Grade II rubber.
  • Designed primarily to convey light aggregate, coal, wood chips, and other materials that do not require high impact resistance.
  • Available as a made-to-order product using Garlocks cover compounds.


GRT DuraKing Belts are general purpose, RMA Grade II belts that provide high performance and long service life. Designed to convey light aggregate, coal, wood chips, and other materials at a very low cost per ton.

DuraKing Belts


Conditions at the point of loading have the greatest effect on belt life and performance. The variables which determine the amount of impact on a belt include:

• Material density
• Freefall
• Lump size
• Contact speed

The impact conditions, in conjunction with the speed of the belt determine th abrasion, cutting and wear forces.

Impact Resistance

FlexKing Belts


Garlock Belts Types

Premium Conveyor Belts

GRT FlexKing® premium conveyor belting is durable and long-lasting. The all-polyester or polyester/nylon carcass with superior adhesion skim compounds can be vulcanized with any GRT cover compound for extra resistance in demanding applications. 

• High-quality conveyor belt for a wide variety of service applications.
• Designed for use in hard rock mining, log handling, aggregate, minerals, and other critical applications.
• Manufactured in widths to 72" (1800 mm).
• Tension ratings from 160 PIW to 1200 PIW.
• Available as a made-to-order product using the cover compounds.

Impact and abrasion are equal to freefall in inches: Impact equals the drop in inches from the end of the chute to the belt plus the equivalent freefall inside the chute. If the chute angle is either 30° or 45° from the horizontal, an equivalent chute freefall calculation can be assigned for different belt speeds.

The length of low-angle chutes is not a factor, since friction restricts the speed of the material to a fairly constant level, regardless of length. However, if a chute angle with the horizontal is over 45°, the impact (freefall in inches) equals the vertical distance from the top of the chute to the surface of the belt.

Technical Data