FluidTech News

 How Does Volumetric Efficiency Decline in Progressive Cavity Pumps? A Step-by-Step Analysis In industrial fluid handling systems, progressive cavity pump (also known as screw pumps) are widely used for transferring viscous, abrasive, and sensitive fluids due to their stable flow and high adaptability. However, during long-term operation, many users notice a common issue: 👉 The pump runs normally, but the flow rate gradually decreases. This is not a sudden failure — it is typically the result of a gradual decline in volumetric efficiency. What Is Volumetric Efficiency? Volumetric efficiency refers to: 👉 Actual flow rate ÷ Theoretical flow rate When internal leakage or slippage increases, the pump delivers less fluid than expected, leading to efficiency loss. The Step-by-Step Formation of Efficiency Decline Understanding how this decline develops is key to preventing costly failures. 1. Initial Stage: Micro Wear Begins At the early stage of operation: Slight wear occurs between ro...

 Abnormal Temperature Rise in Magnetic Pumps: Internal Mechanisms You Should Understand In practical applications, magnetic drive pumps sometimes show a common issue: they continue running normally, but the temperature keeps rising, and in severe cases, may even lead to shutdown. Many users initially attribute this to ambient conditions or insufficient cooling. However, real-world experience shows that: 👉 Abnormal temperature rise in magnetic pumps is often caused by internal mechanisms rather than external factors. Why Are Magnetic Pumps Prone to Heat Accumulation? Magnetic pumps use a magnetic coupling design: No mechanical seal Torque transmitted via inner and outer magnetic rotors A containment shell isolates the fluid from the motor This design ensures leak-free operation, but it also means: 👉 Heat generated inside the pump is harder to dissipate Key Internal Mechanisms Behind Temperature Rise 1. Eddy Current Losses During operation: The outer magnetic rotor rotates at high ...

 How Cavitation Damages Centrifugal Pump Impellers: Key Effects You Should Know Cavitation is one of the most common and destructive problems in centrifugal pump operation. Many users initially notice symptoms such as: Increased noise and vibration Reduced flow rate Unstable performance However, the real issue goes deeper: 👉 Frequent cavitation can gradually destroy the pump impeller. Based on engineering experience from Shanghai Shangcheng Pump & Valve, understanding how cavitation affects the impeller is critical for improving pump reliability and lifespan. What Happens During Cavitation? Cavitation occurs when liquid pressure drops below its vapor pressure, forming vapor bubbles. As these bubbles move into high-pressure regions, they collapse violently, generating shock waves. 👉 These repeated micro-impacts act directly on the impeller surface. How Cavitation Changes the Impeller 1. Pitting and Honeycomb Surface Damage The most typical damage is pitting: Bubble collapse pr...

 Which Parts of Chemical Pumps Fail First in Corrosive Environments? Key Insights for Better Reliability In chemical industries, pumps are often exposed to highly corrosive fluids such as acids, alkalis, and aggressive solvents. Many users assume that as long as the pump casing is corrosion-resistant, the equipment will operate reliably. However, real-world experience shows a different reality: 👉 Pump failures usually start from vulnerable components—not the pump body itself. Based on engineering practices from Shanghai Shangcheng Pump & Valve, understanding these weak points is essential to improving pump lifespan and reducing downtime. 1. Mechanical Seals – The First Failure Point Mechanical seals are widely recognized as the most vulnerable components in corrosive environments. Constant exposure to aggressive chemicals Friction and pressure during operation Temperature fluctuations 👉 These factors make seals highly prone to: Corrosion Leakage Premature failure Studies conf...

 How Pulse Frequency Affects Metering Pump Stability: Key Factors You Should Know In practical applications, many users find that their metering pumps operate normally, yet the flow rate fluctuates or becomes unstable. Based on field experience, this issue is often related to one critical parameter: 👉 pulse frequency setting According to engineering practices from Shanghai Shangcheng Pump & Valve, pulse frequency is not simply “the higher, the better.” Instead, it must be properly matched with operating conditions to ensure stable and accurate dosing. What Is Pulse Frequency in a Metering Pump? A metering pump is a positive displacement pump that delivers fluid through reciprocating motion. 👉 Pulse frequency refers to the number of strokes per unit time For example, certain models can operate at dozens to nearly 100 strokes per minute, depending on design and configuration. This parameter directly affects: Flow continuity Output per stroke Overall dosing accuracy How Pulse Fr...

 What Are the Limits of Rotary Lobe Pumps for Solid-Containing Fluids? Rotary lobe pumps are widely used for handling fluids with suspended solids, but many users misunderstand one key point: they are not unlimited in solids handling capability. Shanghai Shangcheng Pump & Valve Manufacturing Co., Ltd. has found in real-world applications that the performance boundary of rotary lobe pumps depends on multiple factors—not just “whether solids are present.” 1. Particle Size: The Primary Limitation The internal clearance of a rotary lobe pump determines what can physically pass through: Soft solids can be relatively large (even several centimeters in some designs) Hard solids are much more restricted In many standard applications, hard particles are typically limited to around 3 mm, otherwise wear and damage increase significantly Some specially designed pumps can handle larger particles (even up to 90 mm), but only under controlled conditions and with appropriate materials 2. Parti...