Bent-tube flowmeter: Deeply committed to domestic technology, tailored for metering in complex operating conditions.

The bent-tube flowmeter is a differential-pressure flow instrument that offers stable measurement, low pressure loss, and minimal maintenance. It is suitable for applications in the thermoelectric, metallurgical, petrochemical, coking, papermaking, and pharmaceutical industries, and is particularly well-suited to complex operating conditions such as large pipe diameters, dirty or contaminated media, high temperature and high pressure, and severe vibration.

Figure 1: Physical image of the bent-tube flowmeter product

Our company’s ZWZDH series bent‑tube flowmeters are based on technology developed by China’s first domestically‑led R&D team at Hebei Institute of Technology. The original leading expert in domestic bent‑tube flowmeter technology, Professor Tang Jixing, is now with our company. A graduate of Tsinghua University’s inaugural Instrumentation program, Professor Tang has devoted over seventy years to instrumentation research and development. He has participated in the technical攻关 efforts of numerous national key projects in Jilin, Qinghai, Jiangxi, and other regions, personally overseeing the entire lifecycle of China’s bent‑tube flowmeters—from theoretical foundations and experimental validation to industrial field applications. Throughout his career, he has remained at the forefront of R&D, continuously driving product evolution and tackling challenging measurement tasks under complex operating conditions.

The bent-tube flowmeter features no throttling elements and no intrusive measuring probes. It calculates flow rate by leveraging the differential pressure generated as fluid passes through a 90° bend, combined with temperature and pressure compensation. With a measurement range spanning DN10 to DN3000, it effectively addresses common issues associated with conventional flowmeters, such as clogging, component wear, and excessive pressure loss.

Figure 2 Schematic diagram of the differential pressure principle for fluid flow inside an elbow

Bend‑tube flowmeters deliver precise and stable measurements, with typical accuracy of ±1.0% under normal operating conditions and up to ±0.5% after calibration against actual flow. They exhibit minimal long-term drift. Featuring a non‑obstructive internal design, they incur low pressure loss and are resistant to clogging, making them well suited for handling dirty media such as coal gas, slurry, flue gas, and particle‑laden fluids. This helps reduce blockage and wear, lowering maintenance costs, while enabling operation in harsh environments characterized by high temperature, high pressure, dust, and severe vibration. The meters support bidirectional flow measurement, offer an extended service life, and require short straight‑run lengths—typically just 5D upstream and 2D downstream under standard conditions. In older facilities, existing 90° bends can be repurposed without extensive pipeline modifications. For complex flow regimes, the required straight‑run lengths should be determined in accordance with applicable selection guidelines.

Tangshan Fengrun District Zhanwang Automation Equipment Co., Ltd. is a high-tech enterprise integrating the R&D, manufacturing, sales, and system‑engineering integration of flow measurement instruments. The company’s core product lineup includes differential pressure flowmeters, electromagnetic flowmeters, ultrasonic flowmeters, vortex shedding flowmeters, turbine flowmeters, metal‑tube float flowmeters, and variable‑throttle flowmeters, which are widely employed across industries such as metallurgy, chemical processing, thermal power, textiles, food and pharmaceuticals, petroleum, papermaking, nuclear power, shipbuilding, and district heating, providing precise flow measurement solutions for industrial applications. With a comprehensive portfolio of flow‑measurement products, the company builds on the technological legacy of pioneering researchers while adhering to the business philosophy of “integrity first, customers paramount,” thereby contributing to the revitalization of China’s national industry.

Against the backdrop of the industrial sector’s transition toward energy efficiency, carbon reduction, and refined operational control, the performance of flow meters directly impacts enterprises’ energy‑consumption management and production safety. Looking ahead, Automation will continue to deepen its expertise in flow‑measurement technology, offering tailored instrument solutions for diverse operating conditions, and providing domestic flow‑meter products and technical services of proven quality to users across industries, thereby supporting the localization of the flow‑measurement field.

Tangshan Fengrun District Zhanwang Automation Equipment Co., Ltd.

September 18, 2026