Car Tyre Baling: Optimising Baler Settings for Passenger Vehicle Tyres

Updated on: 19th February 2026 By:     Conor Murphy
Expert review by:     Kieran Donnelly

Car tyre baling appears straightforward: load tyres, press start, remove finished bale. However, achieving consistent 900-1,000kg PAS 108-compliant bales requires attention to compression pressure, loading patterns, and cycle timing. Small adjustments in these parameters affect bale weight by 10-20% (900kg vs 750kg) and cycle time by 15-25% (12 minutes vs 15 minutes).

Optimized settings deliver:

• Consistent bale weight (±5% variation vs ±15% unoptimized)
• Reduced cycle time (12-14 minutes vs 15-18 minutes)
• Lower energy consumption (5.2 kWh vs 6.5 kWh per bale)
• Extended equipment life (hydraulic seals last 3,000+ hours vs 2,000 hours)
• Better bale quality (uniform compression, fewer wire failures)

The MKII tyre baler is engineered for car tyre processing with adjustable hydraulic pressure, programmable cycle timing, and multiple loading door configurations. Understanding how these features interact allows operators to optimize for their specific tyre mix and quality targets.

Gradeall International manufactures car tyre baling equipment at our facility in Dungannon, Northern Ireland. The optimization guidance below reflects operational data from customer installations processing 50,000-500,000 car tyres annually across 100+ countries over nearly 40 years.

Hydraulic Pressure Settings

Compression force determines bale density. The MKII’s 7.5kW motor drives a hydraulic pump capable of 180-220 bar pressure. Higher pressure produces denser bales but extends cycle time and increases energy consumption.

Pressure ranges and outcomes:

160-170 bar (low pressure):

• Bale weight: 700-800kg
• Cycle time: 10-11 minutes (fastest)
• Energy per bale: 4.5-5.0 kWh
• Use case: Non-PAS 108 applications (shredding, energy recovery) where density isn’t critical

180-190 bar (standard pressure, recommended):

• Bale weight: 900-1,000kg
• Cycle time: 12-13 minutes
• Energy per bale: 5.2-5.8 kWh
• Use case: PAS 108-compliant bales for construction market (most common)

200-210 bar (high pressure):

• Bale weight: 1,000-1,100kg
• Cycle time: 14-15 minutes
• Energy per bale: 6.2-7.0 kWh
• Use case: Maximum density for transport optimization, premium pricing

220 bar (maximum pressure, not recommended):

• Bale weight: 1,100-1,150kg (marginal improvement)
• Cycle time: 16-17 minutes
• Energy per bale: 7.5-8.5 kWh
• Problems: Accelerated seal wear, overheating risk, wire breakage

Setting pressure:

MKII uses pressure relief valve adjusted via allen key. Factory setting: 190 bar. Adjustment procedure:

1. Run 3-5 compression cycles at current setting
2. Weigh finished bales (establish baseline)
3. Increase pressure 10 bar (turn adjustment screw 2 full turns clockwise)
4. Run 3-5 additional cycles
5. Weigh bales, compare to baseline
6. Repeat until target weight achieved

Most operators find 185-195 bar delivers optimal balance: PAS 108 compliance (900kg+ bales), reasonable cycle time (12-14 minutes), moderate energy use.

Pressure monitoring:

Install pressure gauge on hydraulic system (£150-£250 accessory). Allows visual confirmation of pressure during compression. Pressure should:

• Rise steadily during compression stroke (0 to 190 bar over 4-5 minutes)
• Hold steady at peak (190 bar for 30-60 seconds at full compression)
• Drop to zero on ram retraction

If pressure fails to reach target (plateaus at 170-180 bar), investigate:

• Hydraulic pump wear (reduced output)
• Internal leakage (worn seals allowing pressure bleed-off)
• Relief valve miscalibration

Loading Patterns and Tyre Placement

How tyres are positioned in the compression chamber affects bale density and quality.

Random loading (baseline):

Operator throws tyres into chamber without deliberate arrangement. Tyres land haphazardly, creating voids and uneven distribution.

Result: Bale weight varies 750-950kg (±10% consistency), some areas of bale compressed well, others loosely packed.

Layered loading (improved):

Operator builds layers: place 8-10 tyres flat on chamber floor, add second layer on top, continue until chamber full (typically 9-10 layers, 80-90 tyres total).

Result: Bale weight 850-950kg (±5% consistency), more uniform compression top-to-bottom.

Alternating orientation (optimized):

Operator alternates orientation: first layer lying flat (tread facing up), second layer standing vertical (sidewall facing chamber walls), third layer flat, etc.

Result: Bale weight 920-1,020kg (±3% consistency), tyres interlock reducing voids, best compression uniformity.

Mixed sizing distribution:

When processing tyres of different sizes (car, SUV, van), distribute throughout bale rather than clustering:

Poor: All small tyres at bottom, large tyres at top (uneven compression, bale bulges) Good: Alternate small and large tyres in each layer (consistent compression, stable bale shape)

Time impact:

Random loading: 4-5 minutes per bale (fastest but lowest quality) Layered loading: 5-6 minutes per bale (moderate time, improved quality) Alternating orientation: 6-7 minutes per bale (slowest but highest quality)

For operations selling to construction market (PAS 108 premium pricing), the additional 2 minutes per bale (10% of cycle time) justifies £20-£40/tonne revenue improvement.

Tyre Condition and Preparation

Tyre condition affects compression and bale quality.

Tyre condition categories:

Excellent (recently scrapped, minimal wear):

• Sidewalls intact, minimal cracking
• Compresses readily
• Best for PAS 108 bales

Good (moderate wear, typical):

• Some sidewall weathering, minor cracks
• Compresses normally
• Suitable for all markets

Poor (heavily weathered, significant damage):

• Extensive cracking, chunks missing, dry rot
• Resists compression (brittle rubber doesn’t deform plastically)
• Produces lower-weight bales (820-880kg vs 920-980kg with good tyres)

Aged tyres (5+ years outdoor storage):

• UV degradation makes rubber brittle
• Compression cycle 15-20% longer
• Higher risk of wire breakage (compressed rubber springs back more)

Preparation recommendations:

Inspect tyres during loading. Remove:

• Tyres with severe structural damage (compressed poorly, create voids)
• Mud-caked tyres (add weight without volume, reduce bale rubber content)
• Tyres with rims still attached (steel rims resist compression, reduce bale quality)

Set aside damaged tyres for separate shredding or alternative processing. Don’t attempt to bale tyres unsuitable for compression.

Rim removal:

Some operators bale tyres with rims attached (saves debeading labour). This affects bale characteristics:

With rims:

• Bale weight: 1,050-1,150kg (higher due to steel rim weight)
• Compression: Steel rims resist, creating rigid core in bale
• Market: Shredders accept (separate steel during processing), construction market may reject

Without rims:

• Bale weight: 900-1,000kg (pure rubber weight)
• Compression: Uniform throughout bale
• Market: All markets accept, PAS 108 preferred

For PAS 108 applications, remove rims before baling. For shredding market, baling with rims attached is acceptable and saves labour.

Cycle Timing and Duration

Compression cycle has three phases: load, compress, hold. Timing affects bale quality and energy use.

Load phase (4-7 minutes):

Ram fully retracted, chamber open. Operator loads 80-90 tyres. Duration depends on tyre staging (nearby vs distant) and loading method (random vs optimized).

Target: 5 minutes average. Achieved by pre-staging tyres within 5 metres of baler.

Compress phase (4-6 minutes):

Hydraulic ram extends, compressing tyres from approximately 3 cubic metres to 1 cubic metre. Duration depends on motor power and pressure setting.

7.5kW motor at 190 bar: 5-6 minutes typical Factors extending compression: Cold hydraulic oil (morning startup), worn pump, aged tyres

Hold phase (0-120 seconds):

Ram holds at peak compression before retracting. Purpose: Allow rubber to plastically deform, reducing spring-back after ram retracts.

Hold time settings and effects:

0 seconds hold (immediate retraction):

• Bale springs back 5-8% after ram retracts
• Final bale weight: 850-900kg (spring-back reduces density)
• Wire tension: Higher (resisting spring-back)
• Wire failure rate: 2-3% (excessive tension)

30 seconds hold:

• Bale springs back 3-5%
• Final bale weight: 900-950kg
• Wire tension: Moderate
• Wire failure rate: 0.5-1%

60 seconds hold (recommended):

• Bale springs back 2-3%
• Final bale weight: 920-980kg
• Wire tension: Optimal
• Wire failure rate: <0.5%

120 seconds hold:

• Bale springs back 1-2% (minimal additional benefit vs 60 seconds)
• Final bale weight: 930-990kg (marginal improvement)
• Extended cycle time (adds 60 seconds vs 60-second hold)

Most operators use 45-60 second hold time. Beyond 60 seconds, marginal density improvement doesn’t justify extended cycle time.

Adjusting hold time:

PLC-controlled MKII: Adjust via control panel, enter desired hold time in seconds Relay-controlled systems: Adjust timer module (typically 0-120 second range)

Test different hold times (30s, 45s, 60s, 90s), weigh resulting bales, select setting delivering target weight with minimum cycle time.

Temperature Effects on Compression

Hydraulic oil viscosity varies with temperature, affecting compression performance.

Cold operation (oil below 30°C):

Morning startup, winter operation. High viscosity reduces oil flow through hydraulic system.

Effects:

• Compression phase extends: 7-9 minutes vs 5-6 minutes warm
• Pressure rise slower: Takes longer to reach 190 bar
• Energy consumption higher: Motor works harder pumping viscous oil

Mitigation:

• Allow 5-10 minute warm-up: Run 1-2 compression cycles before loading first productive bale
• Heated storage: Locate baler in heated facility (maintains 15-20°C minimum)

Optimal operation (oil 40-60°C):

After 30-60 minutes operation. Oil reaches optimal viscosity.

Effects:

• Compression phase: 5-6 minutes
• Pressure rise: Steady, predictable
• Energy consumption: Optimal efficiency

Hot operation (oil above 70°C):

Extended operation (6+ hours continuous), summer heat, inadequate cooling.

Effects:

• Viscosity drop increases internal leakage: Pressure plateaus at 175-185 bar (below 190 target)
• Seal degradation accelerates: High temperatures age rubber seals prematurely
• Fire risk (extreme): Oil above 90°C can ignite if sprayed onto hot surfaces

Mitigation:

• Oil cooling system: Factory option or retrofit (£2,000-£3,500)
• Regular breaks: Allow 15 minutes cooling every 3-4 hours continuous operation
• Shade equipment: Avoid direct sun exposure on hydraulic reservoir

Seasonal adjustment:

Winter: Increase hold time 15-20% to compensate for slower compression Summer: Monitor oil temperature, implement cooling breaks if exceeding 70°C Year-round: Track bale weights, adjust pressure ±5 bar seasonally to maintain consistency

Energy Consumption Optimization

Electricity costs money. Optimizing energy use reduces operating costs without sacrificing bale quality.

Baseline energy consumption:

MKII processing car tyres:

• Motor: 7.5kW
• Compression phase: 5 minutes = 0.083 hours
• Energy per compression: 7.5kW × 0.083h = 0.625 kWh
• Idle (loading, wire tying): 0.5kW × 7 minutes = 0.058 kWh
• Total per bale: 0.683 kWh

At £0.25/kWh: £0.17 per bale energy cost

Energy waste sources:

Excessive pressure: Running at 210 bar when 190 bar achieves target weight: Adds 10% energy use (0.75 kWh vs 0.68 kWh) Annual waste (500 bales): 35 kWh = £8.75 (small but avoidable)

Extended hold time: Holding 120 seconds when 60 seconds sufficient: Motor idles at partial load Additional energy: 0.05 kWh per bale × 500 bales = 25 kWh = £6.25 annually

Poor loading: Random loading producing 850kg bales requires processing more tyres to achieve same tonnage vs optimized loading (950kg bales) Example: 500 tonnes output requires 588 bales (850kg) vs 526 bales (950kg) Additional energy: 62 bales × 0.68 kWh = 42 kWh = £10.50 annually

Leaky systems: Hydraulic leaks force pump to work harder maintaining pressure Energy penalty: 5-15% (depending on leak severity) 500 bales × 0.68 kWh × 10% waste = 34 kWh = £8.50 annually

Total optimizable waste: £34 annually (£8.75 + £6.25 + £10.50 + £8.50)

At large scale (5,000 bales annually): £340 annual electricity savings from optimization.

Quality Control and Consistency

Producing consistent bales requires monitoring and adjustment.

Bale weight tracking:

Weigh every 10th bale (5-10% sample). Record weight, date, operator. Plot over time to identify trends:

Consistent weights (±5%): Settings optimal, no adjustment needed Gradual decline (960kg → 920kg → 880kg over weeks): Indicates seal wear or pressure loss, schedule maintenance Sudden variation (950kg, 850kg, 980kg, 820kg): Indicates inconsistent loading or pressure fluctuations, investigate

Visual inspection:

Examine finished bales for:

• Wire tension: All wires taut, no sagging (indicates adequate compression)
• Shape uniformity: Rectangular profile, no bulging (indicates even loading)
• Wire wrap spacing: Wires evenly distributed (prevents localized stress)

Poor bales (bulging, sagging wires): Review loading technique, check pressure setting

PAS 108 compliance verification:

For construction market bales, conduct quarterly compliance testing:

• Select 3 bales randomly
• Weigh each (must be 900kg+ individual, 950kg+ average)
• Measure dimensions (must be within ±50mm tolerance)
• Check wire (minimum 4 wraps, 3.15mm gauge minimum)
• Document results

Failing compliance: Adjust settings (increase pressure 5-10 bar, improve loading technique, add extra wire wrap)

Frequently Asked Questions

Conclusion

Car tyre baling optimization centers on three adjustable parameters: hydraulic pressure (185-195 bar for 900-1,000kg bales), loading pattern (alternating orientation produces ±3% consistency vs ±10% random loading), and compression hold time (45-60 seconds minimizes spring-back without extending cycle unnecessarily).

The MKII tyre baler achieves PAS 108-compliant 920-1,000kg bales with 190 bar pressure, alternating orientation loading, and 60-second hold time. These settings produce 12-14 minute cycle times (vs 15-18 minutes unoptimized) and consistent bale quality suitable for construction market applications (£150-£200 per tonne).

Temperature significantly affects performance. Cold hydraulic oil (morning startup, winter) extends compression 20-40% and reduces effectiveness. Allow 5-10 minute warm-up before productive operation. Hot oil (above 70°C from extended operation) causes internal leakage preventing pressure from reaching target. Install oil cooling or implement 15-minute breaks every 3-4 hours.

Energy optimization through correct pressure settings, appropriate hold time, and efficient loading saves £34-£340 annually (depending on volume) while maintaining or improving bale quality.

Contact Gradeall for detailed optimization guidance specific to your tyre mix, target markets, and processing volumes. We provide commissioning support including settings verification and operator training for optimal car tyre baling performance.

* The prices and running-cost figures below are based on real UK customer examples and are correct at the time of writing, but should be treated as indicative only.

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