Howo Mining Truck Suspension | Leaf Spring vs Hydro-Pneumatic Suspension

Core Summary: For 70t and 90t models, the standard front suspension is semi-elliptical multi-leaf steel spring. For 90t and above heavy-duty KC models, front hydro-pneumatic suspension is available as an option. KC 110t/120t/135t models come factory-equipped with front hydro-pneumatic suspension as standard. The rear suspension for all models is an integral balanced leaf spring suspension (balance shaft), and hydro-pneumatic rear suspension is not offered.

1. Mining Overlord Series (50t/60t/70t, most common in the market)

1. Front Suspension: Semi-elliptical multi-leaf steel spring

   1. Structure: Stacked multi-leaf spring, fixed bracket at one end and sliding shackle structure at the other end. Matched with bidirectional hydraulic shock absorber + anti-roll bar. Equipped with rigid front axle HF12 (12-ton class).

   2. Leaf spring specification: thickness 20 mm, width 100 mm, 12 leaves; front suspension span 1500 mm.

   3. Features:✅ Simple structure, resistant to heavy-load impacts, low maintenance cost, preferred for gravel mines and earth stripping; spare parts are widely available.❌ Stiff ride, severe bumping. Prone to broken leaf springs, frame fatigue and higher tire wear under continuous rough road conditions.

   4. Optional configuration: The 70-ton Mining Overlord cannot be equipped with hydro-pneumatic front suspension; leaf spring is the only factory option.

2. Rear Suspension: Integral balanced leaf spring suspensionDual balance shaft, multi-leaf spring. Classic balanced suspension for 6×4 vehicles, bearing the major load.

2. Howo KC Series Heavy-Duty Mining Trucks (90t /105t /110t /120t /135t)

✅ KC-90t / KC-105t

• Front suspension: Factory standard is leaf spring, hydro-pneumatic suspension is available as an order option (extra cost and longer delivery lead time).

• Front axle upgraded to heavy-duty steering front axle VGK25.

• Rear suspension: Still heavy-duty integral balanced leaf spring suspension. No hydro-pneumatic version for rear suspension.

✅ KC-110t / KC-120t / KC-135t

• Front suspension: Standard hydro-pneumatic suspension (hydro-pneumatic spring). Leaf spring is no longer standard and only available for customized special working conditions.

• Structure: Candle-type hydro-pneumatic spring, single cylinder with accumulator. Hydraulic oil transmits force, inert nitrogen acts as elastic medium with integrated damping. Variable stiffness automatically: stiffens under heavy load and softens under no load. Maintains vehicle body height.

• Rear suspension: 120t/135t adopt new triangular integral balanced leaf spring suspension with large-diameter balance shaft for enhanced torsion resistance. Rear suspension is still not hydro-pneumatic.

3. Comparison: Leaf Spring Front Suspension vs Hydro-Pneumatic Front Suspension (Howo Mining Trucks)

Leaf Spring (Standard for medium & small tonnage)

1. Components: Multi-leaf steel spring + hydraulic shock absorber + stabilizer bar + shackle/bracket

2. Elastic medium: Steel elasticity

3. Advantages: Low cost, easy maintenance, resistance to heavy impacts, less risk of oil leakage at low temperatures; technicians are familiar with servicing. Suitable for continuous heavy load and rough mine operation management.

4. Disadvantages: Poor non-linear performance, harsh bumping. Severe road shocks damage frame, cab and driver. Obvious body height reduction under full load. Leaf springs tend to break, wear between leaves and produce abnormal noise.

Hydro-Pneumatic Suspension (Optional / Standard for heavy-duty KC models)

1. Components: Hydro-pneumatic spring cylinder, high-pressure accumulator, hydraulic pipeline, sealing assembly. No steel leaf spring.

2. Elastic medium: High-pressure nitrogen (elasticity) + hydraulic oil (force transmission + damping)

3. Advantages:

   1. Non-linear stiffness: soft when empty, stiff when fully loaded. Excellent vibration filtering, protects frame and reduces tire wear.

   2. Stable body height, small sinking under full load, better steering geometry retention.

   3. Strong impact resistance. Suitable for large open-pit mines, deep pits and long-distance bumpy haulage, reduces overall vehicle fatigue damage.

4. Disadvantages:

   1. High purchase and maintenance cost. Strict requirements for seals, oil quality and fluid cleanliness.

   2. Oil/gas leakage easily occurs at low temperatures or when seals age. Once the hydro-pneumatic spring fails, long repair downtime and expensive spare parts.

   3. Cylinder outer wall vulnerable to direct impact from sharp large rocks.

4. Two Easy-to-Mix Key Points (Important Notes)

1. The rear suspension of Howo mining trucks always uses balanced leaf spring suspension. Hydro-pneumatic suspension is only used on the front steering axle. There is no full hydro-pneumatic suspension (front & rear) for Howo mining trucks. Many people mistakenly believe large mining trucks adopt full hydro-pneumatic suspension.

2. Hydro-pneumatic suspension is a chassis order option, not random equipment for the same model. If the contract does not specify hydro-pneumatic front suspension for KC90/105, the factory will deliver leaf spring front suspension by default.

5. Model Selection Guide

• Small and medium open-pit mines, earth stripping, limited budget, basic maintenance conditions → 70t Mining Overlord, leaf spring front suspension

• Medium mines with severely potholed roads, requirements to reduce frame fatigue and tire consumption → KC90/105, order optional hydro-pneumatic front suspension

• Large open-pit mines, heavy-duty long-distance transport, deep pit operation with large elevation difference → KC110 and above, standard hydro-pneumatic front suspension