What TKPH Means And Why It Matters In Quarries
TKPH (tonne‑kilometres per hour) is a tyre heat‑capacity rating. It combines the average load carried by each tyre with the average operating speed to predict the heat the casing must dissipate. If site TKPH exceeds the tyre’s rating, heat builds faster than it can escape, leading to tread separations, rapid wear and sidewall fatigue.
TKPH and TMPH are the same concept expressed in different units (tonnes vs US tons; 1 US ton ≈ 0.907 t). Always compare ratings within the same brand data book, as methods and ambient references vary. Quarry duty is heat‑driven: haul length, gradients, ambient temperature, rolling resistance and stop/start patterns all push casing temperature. Fieldens OTR Ltd specifies tyres for real UK quarry cycles—not brochure conditions. For product options see our industrial tyres, and for harsh‑environment context read demanding conditions for rim and tire.
How To Calculate Site TKPH Correctly
Capture accurate cycle data before you choose a tyre:
- Laden and empty gross vehicle weight; payload per cycle.
- Axle load distribution and number of tyres per axle.
- Haul distances for laden and empty legs; gradient % on each leg.
- True average cycle speed: total distance divided by total time, including queue, dump and turn.
- Ambient temperature range and road surface/rolling resistance.
Working method: Site TKPH ≈ average load per tyre (t) × average speed (km/h). Average load per tyre is typically [(laden GVW + empty GVW) ÷ 2] ÷ number of tyres. Many brands quote ratings at a reference ambient (often ~38°C); cooler UK conditions may allow a correction factor—confirm per brand.
Mini‑example: (105 t laden + 45 t empty) ÷ 2 ÷ 6 tyres = 12.5 t/tyre. At 23 km/h, Site TKPH ≈ 288. Select a tyre with a higher rated TKPH to maintain a safe margin.
TKPH By Machine Type: Rigid Trucks, Quarry Dumpers And Loaders
Rigid haul trucks run longer hauls at sustained speeds, so TKPH and heat resistance are the limiting factors. Typical choice: E4 tread with a heat‑resistant compound for long runs, plus strict speed discipline on ramps and flats.
Articulated dump trucks (ADTs) face mixed terrain and speeds. Balance cut resistance with adequate TKPH. An E3/E4 pattern often suits cycles that mix sharp rock with short road sections.
Wheel loaders work short, intense cycles with high torque, repeated turns and face‑work. L5 offers maximum cut protection and casing strength; TKPH still matters if loaders tram further or faster between stockpiles. For packaged support across machines, see our industrial tyre and wheel package deal.
This image was generated with AI and may not always represent the product or service exactly.
Choosing The Right Compound And Tread Design
Match compound to the real duty:
- Heat‑resistant compounds: high‑TKPH routes and steady speeds.
- Cut‑resistant compounds: sharp rock, loading areas and shot faces.
- Balanced compounds: mixed duty where both heat and cuts are risks.
E‑patterns suit transport (E3 general, E4 deeper for longer hauls). L‑patterns suit loaders/dozers (L3 versatile, L5 deepest for cut protection). Deeper tread carries more rubber and can retain more heat, so check TKPH margins. Sidewall and shoulder protection, belt packages and robust bead design improve stability on heavy rims. Fieldens OTR Ltd specifies Michelin, BKT and ATG against measured site TKPH and cut severity.
Heat Management On Site: Keep TKPH Under Control
Control heat with disciplined basics:
- Set correct cold pressures; verify hot pressures against brand guidance.
- Cap peak speeds; enforce limits on ramps and longer straights.
- Grade and water haul roads to cut rolling resistance and dust.
- Manage queue times; avoid sustained overloads; allow cooling windows in hot spells.
- Use TPMS or spot‑check carcass temperatures with an infrared thermometer.
Polycoat Tyrefill suits puncture‑prone, low to moderate speed work (e.g. loaders, site support). Avoid it on high‑TKPH, faster hauls as fill retains heat. See tyrefill for where it works best. A short site survey by Fieldens OTR Ltd will tune speeds, loads and cooling intervals to your cycle.
Rotation Plans, Matching And Inspection Routines
Set rotation by hours and wear rate. For loaders, rotate every 150–250 hours or when shoulder wear diverges. For rigid trucks and ADTs, swap positions at agreed tread‑depth differences to even wear and temperature. If your model runs duals, closely match diameters and tread depths to prevent overloading and overheating one tyre.
Record hours, positions, pressure checks, heat signs (bluing, rubber reversion), cut growth and repairs. Remove tyres with bulges, exposed cords or repeated hot caps. Fieldens OTR Ltd provides on‑truck fitment and planned rotations—see delivery and fitting for UK‑wide support.
Wheels Matter: Specification, Fitment And ISO 9001 Quality
Correct wheel specification protects tyres and shares load. Confirm hub‑piloted vs stud‑piloted systems, PCD, offset and centre‑bore tolerances. Bespoke wheels can be engineered for impact, cooling and TKPH duty, with coatings to control corrosion. Fieldens OTR Ltd designs and builds to ISO 9001, delivering matched tyre‑and‑wheel packages for quarry service.
Precision fitment matters: clean mating faces, correct torque sequence and re‑torque after the first shift. Inspect multi‑piece components, O‑rings and valve hardware. If you need a custom build, explore our bespoke wheels, and read our guide on stud vs hub piloted, PCD, centre bore and offset for heavy equipment.
This image was generated with AI and may not always represent the product or service exactly.
Worked Examples: UK Quarry Duty Scenarios
Rigid haul truck: Payload 60 t; empty 45 t; laden 105 t; six tyres; average cycle speed 25 km/h. Average load/tyre = (105 + 45) ÷ 2 ÷ 6 = 12.5 t. Site TKPH ≈ 12.5 × 25 = 313. Choose an E4 heat‑resistant compound with TKPH comfortably above 313, and enforce ramp speed limits.
Articulated dumper: Payload 25 t; empty 20 t; laden 45 t; six tyres; average 20 km/h across mixed gradients. Average load/tyre = (45 + 20) ÷ 2 ÷ 6 ≈ 5.4 t. Site TKPH ≈ 5.4 × 20 ≈ 108. A balanced E3/E4 with adequate TKPH and good cut resistance suits this duty.
Wheel loader: 50 t operating weight; short, repeated cycles; 400 m tramming between stockpiles at 10 km/h. Average load/tyre ≈ 50 ÷ 4 = 12.5 t (bucket loads are brief transients). Site TKPH ≈ 12.5 × 10 = 125. L5 is preferred for cut protection; check TKPH if travel distances or speeds rise. Monitor pressures and allow cool‑off pauses in hot weather.
Common TKPH Pitfalls And How To Avoid Them
- Using peak speed instead of true average cycle speed.
- Ignoring empty‑leg loads, queue and dump times.
- Skipping ambient temperature adjustments in hot spells.
- Under‑inflation, which increases flexing and heat.
- Mixing compounds or patterns on the same axle.
- Not matching diameters on duals, overloading one tyre.
- Fixes: capture real cycle data, lock inflation routines, standardise patterns and record loads.
- Audit roads and speeds regularly; refresh operator briefings.
Fieldens OTR: Survey, Specify, Supply And Fit
Fieldens OTR Ltd surveys your site, calculates TKPH, and specifies tyres, compounds and treads that fit the duty. We design and build bespoke wheels to ISO 9001 and provide precision delivery, fitting and aftercare across the UK. We source from Michelin, BKT and ATG, and recommend Polycoat Tyrefill where it adds value.
Ready to optimise tyre life and cut heat‑related downtime? Book a site survey or send us your cycle data. Our engineers will return a clear recommendation that balances reliability, durability and lifecycle cost.
FAQs
Is TKPH The Same As TMPH?
Yes. TKPH uses metric tonnes; TMPH uses US tons (1 US ton ≈ 0.907 t). The principle is the same—compare like‑for‑like within the same brand data book.
How Close Can I Run To The Rated TKPH?
Leave a margin. Real cycles vary with weather, road condition and traffic. We typically target at least a 10–20% buffer above measured site TKPH, subject to brand guidance.
Do Deeper Treads Increase Heat?
They can. More rubber retains more heat. If you choose E4 or L5 for wear and cut protection, confirm the TKPH still covers the duty.
Can I Use Tyrefill On Haul Trucks?
Not recommended for high‑TKPH, faster haul cycles because fill retains heat. It suits low to moderate speed, puncture‑prone work such as loaders.
How Often Should We Rotate Loader Tyres?
Every 150–250 hours or when shoulder wear diverges, whichever comes first. Inspect weekly and log positions to keep pairs even.
What Wheel Details Do You Need For A Quote?
Hub or stud‑piloted, PCD, centre bore, offset, load duty and current tyre size. Photos of the hub and stampings help us verify.