In China VI vehicle exhaust systems, apart from major components such as exhaust pipes and mufflers, there is one small yet vital part—the cold-drawn differential pressure tube—acting as the "data scout" for DPF particulate traps.
The differential pressure tube connects to both the inlet and outlet ends of the particulate filter, measuring the pressure difference between the two sides and transmitting this data to a differential pressure sensor.
The vehicle's ECU relies on this information to assess DPF soot accumulation and automatically initiate regeneration. Any leakage or deformation in the tube can lead to inaccurate readings, triggering fault codes, torque and speed limitations, and disrupting normal vehicle operation.
Conventional tubes often suffer from uneven wall thickness and weld seams, making them prone to collapsing during bending and highly susceptible to leaks under prolonged high-temperature and vibrational conditions. In contrast, cold-drawn differential pressure tubes offer significant advantages: uniform wall thickness, tight dimensional tolerances, smooth inner surfaces without welds, superior airtightness, excellent heat resistance and vibration resistance, and strong resistance to deformation during bending—ensuring long-term, stable, and accurate pressure differential measurements.
As a leading manufacturer specializing in stainless steel processing for automotive exhaust systems, Harmony way steel has been consistently supplying raw materials and precision machining services for cold-drawn differential pressure tubes. We offer customized processing including uncoiling, slitting, bending, and cutting according to customer requirements, strictly controlling tube accuracy and airtightness to meet the production needs of major automotive parts manufacturers.
Though small in size, the differential pressure tube plays a crucial role in ensuring the stable operation of the entire exhaust aftertreatment system. With our precision machining, we uphold quality in every detail, providing reliable tubing solutions for domestic automotive exhaust component manufacturers.
