Technical Data

Core Advantages of Firing Temperature Curve with Heavy Oil Burner in Fired Brick Tunnel Kilns

I. Advantages for Fired Product Quality

(1) Uniform temperature field across the entire kiln, significantly reducing color differences and deformation defects

The heavy oil burner achieves thorough atomization, producing a soft and elongated flame that forms a continuously stable temperature curve along both the width and length of the tunnel kiln—without localized hot spots or cold dead zones. Conventional firing equipment tends to cause surface blistering and warping due to localized overheating, while low-temperature areas on both sides lead to underfiring and color discrepancies. The stable gradient temperature field of the heavy oil burner ensures that every green brick undergoes heating, soaking, and cooling in perfect synchrony, resulting in uniform color throughout and consistent internal crystallization, thereby substantially reducing the reject rate.

(2) Precisely matching the segmented firing process curve to enhance structural strength

Fired brick production is divided into four distinct temperature‑controlled zones: preheating, firing, soaking, and cooling. The heavy oil burner allows flexible adjustment of firing intensity, accurately replicating the standard process temperature curve: slow heating and moisture removal in the preheating zone, constant‑temperature soaking in the firing zone for crystal phase sintering, and controlled cooling in the soaking zone to relieve internal stress. This stable curve prevents cracking caused by rapid heating and internal fissures from thermal shock, improving the compressive strength and frost resistance of finished products. The durability of facing bricks and paving bricks is notably enhanced.

(3) Sustained stable temperature in the soaking zone, ensuring consistent quality across large‑volume production

The heavy oil storage and supply system maintains stable pressure with minimal fluctuations in calorific value, so the high‑temperature soaking section of the firing curve shows no major swings. Within the same kiln and across multiple batches, the degree of sintering is uniform, eliminating the mixed occurrence of underfired and overfired bricks in one load. Under mass production, product parameters are standardized, meeting the uniform quality requirements for engineering procurement.

II. Advantages in Terms of Temperature Control

(1) Stepless flame adjustment for precise, zone‑by‑zone temperature curve control

The heavy oil burner is equipped with an integrated oil pressure and air flow linkage regulating mechanism, enabling seamless switching between high and low flame outputs and independent control of the heat output from each burner group in the tunnel kiln. It can tailor a gradual rising heating curve, a flat constant‑temperature firing curve, or a linear slow‑cooling curve as needed, flexibly adapting to the specific firing profiles of different brick types—clay bricks, antique decorative bricks, dry‑pressed bricks, etc.—offering strong process adaptability.

(2) Gentle temperature response, smooth curves with high fault tolerance for temperature control

Compared to fuels with intense instantaneous combustion output, the atomized heavy oil combustion delivers a softer heat release. After adjusting the firing intensity, kiln temperature changes gradually, resulting in a smooth curve without abrupt spikes or drops. This prevents sudden temperature differentials from disrupting the preset firing profile, reduces the burden on the temperature control system, and ensures that either manual or PLC‑based automatic regulation can reliably maintain the set curve.

(3) Uniform heat supply over long distances, providing a well‑graded temperature profile across the entire kiln

The heavy oil flame has moderate throw and evenly distributed thermal radiation, forming a continuous gradient temperature curve along the kiln length. The temperature rises linearly and steadily from the preheating zone to the firing zone, with no gaps or thermal discontinuities. The temperature differentials across the kiln cross‑section (top‑bottom and side‑side) are kept within a very narrow range, and the overall kiln temperature curve conforms to the process design standards, eliminating process instability caused by local curve imbalances.

(4) Continuous 24‑hour stable output with long‑term curve consistency

The heavy oil fuel has a stable calorific value, and the burner is resistant to nozzle clogging and flashback, enabling round‑the‑clock continuous operation. The kiln temperature curve does not shift or sag during day‑night shifts or crew changes. There is no need for frequent manual corrections of combustion parameters; the standard firing curve is maintained over the long term, reducing energy waste and process risks associated with repeated adjustments due to temperature fluctuations.