Understanding the Bomag BF 600 P-2 Screed Heating System
The Bomag BF 600 P-2 is a robust tracked paver widely used across UK highway and infrastructure projects for its consistent mat quality and reliable screed performance. At the heart of this machine lies the screed heating system, a hydraulically powered array that ensures the screed plates reach and maintain the correct temperature for asphalt compaction. Without proper maintenance and performance optimisation, cold spots, uneven heat distribution, and premature component wear can lead to costly downtime and poor surface finish.
This article provides practical, hands-on advice for enhancing the performance of the Bomag BF 600 P-2 screed heating system through diligent care and regular maintenance. Whether you are a site foreman or a plant fitter, these tips will help you keep the screed heating at peak efficiency, reducing fuel consumption and extending service intervals.
How Often Should I Inspect the Screed Heating Burners?
The burner assembly is the primary heat source for the screed plates. Regular inspection is critical to avoid incomplete combustion, which wastes diesel and produces excessive soot. For the Bomag BF 600 P-2, a visual check of the burner nozzles and ignition electrodes should be performed every 50 operating hours, especially during heavy use in spring and autumn.
Every 250 hours, a more thorough inspection is recommended. Key items to examine include:
- Nozzle condition: Look for carbon deposits or blockages. Clean or replace nozzles using OEM Bomag parts (part number 059 450 01).
- Electrode gap: The gap should be set to 3.5 mm ± 0.5 mm. Too wide or too narrow will cause misfiring.
- Fuel line filters: Replace the primary and secondary fuel filters every 500 hours to ensure clean diesel reaches the burner.
If you suspect issues with material feed interfering with screed heating, consult the Bomag BF 600 P-2 Material Feed System Troubleshooting Guide for linked diagnostic steps.
What Are the Correct Temperature Settings for the Screed Plates?
Operating the screed at the wrong temperature can cause poor compaction, surface tearing, or overheating damage. The Bomag BF 600 P-2 has a control panel that allows the operator to set target temperatures for the left and right screed sections independently. For standard dense-graded asphalt (DGA), the recommended plate temperature is between 120°C and 150°C, depending on ambient conditions and mix type.
When using polymer-modified binders, increase the target to 160°C–170°C. Never exceed 180°C, as this risks warping the screed plate and damaging the hydraulic motors that drive the heating circulation pump. Use an infrared thermometer to verify actual plate temperature against the gauge reading at least once per shift.
| Mix Type | Recommended Plate Temperature (°C) | Maximum Plate Temperature (°C) |
|---|---|---|
| Dense-Graded Asphalt (DGA) | 120–150 | 170 |
| Polymer-Modified Asphalt | 160–170 | 180 |
| Thin Overlay / SMA | 130–155 | 175 |
| Warm Mix Asphalt | 110–130 | 155 |
Always allow the screed to preheat for at least 15 minutes before starting a paving pass. Rapid heating can cause thermal shock, leading to cracked welds. For more on preventing damage from thermal stress, see the Bomag BF 600 P-2 Corrosion Prevention Guide: Extending Paver Life.
How Can I Improve Heat Distribution Across the Screed?
Even heat distribution is essential for a uniform mat surface. Common causes of uneven heating include clogged hydraulic oil filters, worn circulation pump seals, or air in the hydraulic circuit. On the Bomag BF 600 P-2, the heating system uses a dedicated hydraulic pump that circulates oil through heating elements beneath the screed plates.
To improve distribution, follow these maintenance steps:
- Check hydraulic oil level and condition: Low oil or contaminated oil will reduce flow. Change the hydraulic oil every 2000 hours or annually, whichever comes first.
- Bleed air from the system: After servicing, operate the screed heating at low temperature (80°C) for five minutes to purge air pockets. Listen for irregular pump noise—this indicates cavitation.
- Inspect the heating elements: Use a multimeter to test resistance across each element. A reading outside 10–20 ohms suggests a failed element needing replacement.
If the screed still shows temperature variance of more than 10°C across its width, inspect the track alignment as well—misalignment can cause uneven load on the screed. Refer to the Bomag BF 600 P-2 Track System Maintenance: A Comprehensive Guide for track-related adjustments.
What Is the Correct Procedure for Cleaning the Screed Plates?
Accumulated asphalt residue on the screed plates acts as an insulator, reducing heat transfer efficiency. For the Bomag BF 600 P-2, daily cleaning is non-negotiable if you want to maintain screed heating performance. Use a long-handled scraper with a brass or plastic blade to avoid scratching the chrome finish of the screed plate.
The correct procedure is:
- Cool down the screed: Allow the screed to cool to below 80°C before cleaning. Hot cleaning risks burns and can cause the asphalt to re-adhere.
- Apply a biodegradable release agent: Spray a thin coat of vegetable-based release agent onto the warm plate. Let it sit for 2–3 minutes to break down the asphalt bond.
- Scrape gently: Work from the outer edges toward the centre. Avoid using metal scrapers, which can gouge the plate.
- Wipe with a clean rag: Remove all residue and release agent. A clean plate heats faster and more evenly.
Never use diesel or kerosene as a cleaning solvent—these can damage the hydraulic seals and create a fire hazard. For weekly deep cleaning, consider using a steam cleaner set to low pressure (max 100 bar) to avoid damaging the electrical connections in the heating system.
How Can I Troubleshoot a Non-Heating Screed Section?
If one side of the Bomag BF 600 P-2 screed fails to heat, the issue often lies in the independent control circuit for that section. The paver has two separate heating zones, each controlled by a relay and a temperature sensor (thermocouple). When one side remains cold, start with the simplest checks.
First, verify that the circuit breaker for that side has not tripped. The breakers are located in the main electrical panel behind the operator’s seat. Reset the breaker if needed, but investigate if it trips again immediately. Common causes include:
- Short circuit: Damaged wiring insulation near the screed hinge points. Inspect the harness for chafing or cuts.
- Failed thermocouple: Use a multimeter to measure resistance across the thermocouple. At room temperature (20°C), it should read approximately 1100 ohms. A short or open circuit indicates replacement is needed.
- Relay stuck open or closed: Swap the relay from the working side to the non-working side. If the problem moves, the relay is faulty.
If electrical components check out, move to the hydraulic side. A failed flow divider valve can starve one section of hot hydraulic oil. Test by measuring the temperature of the return lines from each screed section—the side that is significantly cooler likely has restricted flow. For a systematic approach to diagnosing feed-related issues, see the Bomag BF 600 P-2 Material Feed System Upgrade Guide.
What Owners Say About the Bomag BF 600 P-2 Screed Heating
Operators and fleet managers who have worked extensively with the Bomag BF 600 P-2 consistently praise its screed heating system’s reliability when properly maintained. One UK contractor operating two units in Gloucestershire reported that after switching to a strict 250-hour burner inspection schedule, their average screed temperature variance dropped from 15°C to just 4°C, improving mat density consistency by 8%.
Another owner, a civil engineering firm based in Yorkshire, noted that upgrading to premium synthetic hydraulic oil (ISO VG 46) extended the life of the heating pump seals by nearly 600 hours. They recommend budgeting approximately £650 per year for synthetic oil changes compared to £350 for standard mineral oil, but the longer component life offsets the cost.
However, some operators have experienced intermittent heating faults that were traced to corroded thermocouple connectors, especially on machines used in coastal environments. The Bomag BF 600 P-2 Corrosion Prevention Guide: Extending Paver Life offers specific recommendations for protecting these connectors with dielectric grease and stainless steel caps.
Overall, the consensus is that the Bomag BF 600 P-2 screed heating system delivers reliable performance as long as the owner invests in regular cleaning, quality burner parts, and proactive hydraulic maintenance. Heat-up time to operating temperature (130°C) typically takes 18–22 minutes from cold start, which is competitive in its class.
Frequently Asked Questions
Q1: What is the average service life of the screed heating burner assembly?
With proper maintenance, the burner assembly can last 4,000–6,000 hours. Replace nozzles every 500 hours and igniter electrodes every 1,000 hours for best performance.
Q2: Can I use the Bomag BF 600 P-2 for warm mix asphalt without modifying the heating system?
Yes. The standard heating system can handle warm mix asphalt at temperatures as low as 110°C. Ensure the control panel is set to the lower range to avoid overheating the mix.
Q3: Why does my screed temperature fluctuate during paving?
Fluctuations often result from a dirty hydraulic oil filter restricting flow. Replace the filter (part number 060 250 02) and check the oil level. Also, verify that the thermocouple is clean and properly seated.
Q4: How do I know if the hydraulic circulation pump is failing?
Signs include unusual grinding or whining noise from the pump area, intermittent heating, or a temperature increase of more than 20°C between the pump inlet and outlet. Replace the pump if flow rate drops below 12 L/min.
Q5: Is it safe to operate the screed heating system while the paver is moving?
Yes, the system is designed to operate during paving. However, always engage the heating before starting the paver to allow the screed to reach temperature. Avoid leaving the heating on when stationary for extended periods (over 10 minutes) to prevent overheating the hydraulic fluid.
Q6: What should I do if the screed heating system triggers an overtemperature alarm?
Immediately reduce the set temperature on the control panel by 20°C. Check the hydraulic oil cooler for blockages and clean the fins. If the alarm persists, the temperature sensor may be faulty—replace it with OEM part number 059 480 05. For engine-related overheating, refer to the Bomag BF 600 P-2 Engine Overheating Troubleshooting Guide.