FluidTech News

 What Causes Screw Pump Seal Failure? Key Factors You Shouldn’t Ignore In industrial fluid handling, screw pumps are widely used for their stable flow, low pulsation, and strong ability to handle high-viscosity or particle-laden media. However, in real-world applications, one issue still shows up frequently: seal failure. From an engineering perspective, it’s fair to say that choosing the right pump is only half the job—whether the sealing system is reliable often determines how long the pump can run without trouble. So what actually causes screw pump seal failure? Here are the key factors. 1. Fluid Characteristics: The Most Overlooked Factor Many users focus on flow rate and pressure, but overlook how the fluid itself affects sealing performance. Typical risks include: High viscosity → increases friction and heat Solid particles → cause abrasion and scratches Corrosive media → attack sealing materials Crystallizing fluids → deposit around seal faces 👉 In many cases, seal failure ...

 Why does a magnetic drive pump feel “weaker” under high-temperature conditions? Many users notice this situation: the pump is still running, but the flow rate drops, and it feels like it can’t deliver enough power. The first reaction is often that the pump is failing—but that’s not always the case. The real issue is often related to the magnets. A magnetic drive pump relies on magnetic coupling. The motor drives the outer magnet, which transfers torque to the inner magnet through a magnetic field, and then drives the impeller. There is no direct mechanical contact, so once the magnetic force weakens, the pump’s performance drops. High temperature is one of the key factors affecting magnet performance. As temperature rises, the magnetic strength gradually decreases. This reduces the torque that can be transmitted, leading to lower flow rate and reduced efficiency. The pump is still running, but it’s no longer performing effectively. If the temperature exceeds a certain limit, irrev...

 Why Is Your Rotary Lobe Pump Getting Noisier? Common Causes Explained Rotary lobe pumps are widely used in industries such as food processing, pharmaceuticals, cosmetics, and fine chemicals due to their low shear, stable flow, and gentle handling of fluids. Under normal conditions, these pumps operate smoothly with low noise and minimal vibration. However, after a period of operation, some users begin to notice: 👉 Increased noise levels, abnormal sounds, or even vibration Many assume this is simply due to equipment aging. But in reality: 👉 Rising noise is often an early warning signal—not the root problem itself. For more technical insights and pump-related information, you can also refer to: 👉 https://www.scpv.cn/news/873.html 1. What Is “Normal” Sound for a Rotary Lobe Pump? A properly operating rotary lobe pump typically produces: Smooth and continuous sound Low-frequency hum Minimal vibration If you start hearing: Metallic scraping Intermittent knocking High-pitched noise ?...

 CDL Vertical Stainless Steel Multistage Pump: Impact of Internal Leakage on Overall Performance In water supply boosting, industrial circulation, and water treatment systems, the CDL vertical stainless steel multistage pump is widely used for its compact design, stable operation, and high efficiency. However, after long-term operation, a critical yet often overlooked issue emerges — internal leakage. It’s important to understand: 👉 Internal leakage is not a sudden failure, but the starting point of performance degradation. For product details and specifications, visit: 👉 https://www.scpv.cn/pumps/CDL.html 1. Why Internal Leakage Exists in Multistage Pumps Multistage pumps like CDL rely on multiple impellers to increase pressure step by step. Due to structural requirements, small clearances must exist between components: Impeller and diffuser Wear rings (clearance seals) Shaft sleeve and sealing areas These clearances are necessary for operation, but they also create natural leak...

 Chemical Pump Flow Fluctuation: Common Causes and Analysis Chemical pumps are widely used in petrochemical, wastewater treatment, and process industries. During operation, unstable or fluctuating flow rate is one of the most common issues that can affect production efficiency, system stability, and equipment lifespan. This article summarizes the most common causes of chemical pump flow fluctuation and provides practical engineering insights for troubleshooting. For more chemical pump products and technical details, please visit: https://www.scpv.cn/huagongbeng/ 1. Operation Far from Best Efficiency Point (BEP) One of the primary reasons for flow instability is operating the pump far away from its Best Efficiency Point (BEP). When a centrifugal pump runs under low-flow or overload conditions: Internal recirculation increases Flow separation occurs Pressure and discharge become unstable This leads to periodic flow oscillation and unstable output. 2. Suction Side Problems (Air or Cav...

 Sewage Pump Flow Reduction: Is It a Pump Problem or a Piping System Issue? In municipal drainage, wastewater treatment, and industrial effluent transfer, sewage pumps are expected to deliver stable performance over long periods. However, a common issue observed on-site is: 👉 Flow rate gradually decreases while the pump is still running Many users immediately assume: 👉 “The pump efficiency has dropped—it needs repair or replacement” But in real engineering practice, a more common cause is: 👉 The piping system is restricting the pump performance 👉 Reference products and applications: https://www.scpv.cn/paiwubeng/ 1. Key point: flow reduction ≠ pump failure It’s a common misconception that: 👉 Flow rate = pump capability In reality: 👉 Flow rate = pump + system interaction Any change in system resistance will directly affect flow. 2. Cause #1: Pipeline blockage (most common) Sewage systems typically involve: High solids content Sediment accumulation Fibrous materials When pipeli...

ISG Pipeline Centrifugal Pump Bearing Overheating: Is It Always a Lubrication Problem? In HVAC circulation systems, water supply networks, and industrial fluid transport, ISG pipeline centrifugal pumps are widely used for their compact structure and stable operation. However, one common issue frequently observed on-site is: 👉 Bearing overheating during operation Many operators immediately assume: 👉 “It must be a lubrication issue” But real-world engineering experience shows that: 👉 Lubrication is only one of several possible causes 👉 Reference analysis: https://www.scpv.cn/news/880.html 1. First principle: why do bearings overheat? The root cause of bearing overheating is: 👉 Increased friction and abnormal load Lubrication affects friction—but it is not the only factor. 2. Lubrication issues (yes, but not the whole story) Typical lubrication-related causes include: Insufficient or excessive grease Degraded or contaminated lubricant Incorrect lubricant type These conditions can: 👉...

 Self-Priming Pump Flow Interruption: It’s Usually Not the Pump—But the System Behind It Self-priming pumps are widely used in municipal drainage, chemical transfer, and irrigation systems thanks to their ability to evacuate air and start without external priming. However, a common issue in real operations is: 👉 Flow suddenly stops during operation, or becomes intermittent Many users assume pump failure. In reality, most cases are caused by: 👉 Changes in system conditions, not the pump itself 👉 Reference analysis: https://www.scpv.cn/news/868.html 1. What “flow interruption” really means Typical symptoms include: Sudden loss of discharge Significant flow reduction Intermittent pumping behavior 👉 In essence: The pump fails to maintain a stable suction condition. 2. Cause #1: Air leakage on the suction side (most critical) Self-priming pumps are highly sensitive to air ingress. If there is: Loose pipe connections Worn gaskets Micro-leaks in suction piping It leads to: 👉 Air ente...

Screw Pump Seal Failure: It’s Usually Not the Seal—But the Operating Conditions Behind It In industries such as wastewater treatment, oil transfer, and chemical processing, screw pumps are widely used for their stable flow and ability to handle viscous media. However, a common issue many sites face is: 👉 Seal leakage after a period of operation Even after replacing the seal, the problem often returns quickly. 👉 Reference analysis: https://www.scpv.cn/news/874.html From real engineering experience, this is rarely a “seal quality issue.” More often, it is: 👉 Operating conditions continuously damaging the seal 1. Key point: seal failure is a result, not the root cause For a seal (mechanical seal or packing) to work properly, it requires: Proper lubrication Stable temperature Balanced pressure Consistent mechanical alignment If any of these conditions are compromised: 👉 Seal failure becomes inevitable 2. Cause #1: Dry running (most critical factor) When the pump operates under: Insuffi...

Diaphragm Pump Air Distribution System Failure: The Hidden Chain Reactions Behind Unstable Operation In industries such as chemical processing, wastewater treatment, and coating, diaphragm pumps are widely used for their reliability and ability to handle viscous or particle-laden fluids. However, many systems encounter a common issue over time: 👉 The pump is still running, but performance becomes unstable Typical symptoms include fluctuating flow, increased air consumption, and frequent diaphragm replacement. In many cases, the root cause is not the diaphragm itself, but: 👉 A malfunction in the air distribution (valve shifting) system 👉 Reference analysis: https://www.scpv.cn/news/875.html 1. Why is the air distribution system so critical? The working principle of a diaphragm pump is: 👉 Compressed air drives the diaphragm in a reciprocating motion The air distribution system controls: 👉 The switching of air between chambers In simple terms: 👉 It acts as the “timing controller” of...

 What Does Current Fluctuation in Magnetic Drive Pumps Really Indicate? Hidden System Issues You Shouldn’t Ignore In chemical processing, environmental engineering, and electroplating industries, magnetic drive pumps are widely used due to their leak-free design. However, a common issue observed in real operations is: 👉 Motor current fluctuates during operation Many assume it’s an electrical fault. In reality, current fluctuation is often a signal that: 👉 The system operating condition is changing 👉 Reference analysis: https://www.scpv.cn/news/877.html 1. What does current fluctuation mean? Motor current directly reflects load changes: Higher current → higher load Lower current → lower load So when current keeps fluctuating: 👉 The pump load is unstable And that instability usually comes from the system, not just the motor. 2. Cause #1: Flow instability in the system If the system has: Frequent valve adjustments Variable demand points Pressure fluctuations Then: 👉 Flow rate kee...

Why Does Efficiency Drop in Sanitary Stainless Steel Rotary Lobe Pumps? Common Causes You Shouldn’t Ignore In industries such as food processing, pharmaceuticals, and cosmetics, sanitary stainless steel rotary lobe pumps are widely used for their gentle handling, stable flow, and easy cleaning. However, after a period of operation, many users notice the same issue: 👉 Flow rate decreases, discharge slows down, and energy consumption increases The common reaction is to assume the pump is worn out or needs replacement. But in most real-world cases, the problem is not pump failure—it is: 👉 A gradual loss of efficiency 👉 Reference case and analysis: https://www.scpv.cn/news/873.html 1. What does “efficiency drop” really mean? Rotary lobe pumps are positive displacement pumps, which means: 👉 Each rotation should deliver a fixed volume of fluid When efficiency drops: 👉 Actual output becomes lower than theoretical output The core issue is simple: 👉 Internal losses are increasing 2. Cause...

 How Much Does Axial Force Variation Affect CDLF Vertical Multistage Pumps? (An Overlooked Risk in Real Projects) Opening: Straight to the point In many projects using CDLF vertical stainless steel multistage pumps, attention is usually placed on flow rate, head, and material. But in real operation, a more critical factor is often ignored: 👉 Axial force imbalance over time From engineering experience, many “unexpected failures” are not caused by material defects, but by uncontrolled axial force. That’s why experienced manufacturers like Shanghai Shangcheng Pump & Valve tend to focus on force balance during selection—not just performance parameters. 👉 Product reference (structure & parameters): https://www.scpv.cn/pumps/CDLF.html 1. What is axial force? In simple terms: 👉 Axial force = the thrust generated by pressure differences acting on the impeller CDLF pumps are vertical multistage centrifugal pumps, meaning: Multiple impellers are arranged in series Each stage gener...

 Risk Mechanism Analysis of IHF Fluoroplastic Chemical Pumps Handling Volatile Media (with Engineering Solutions) In chemical processing systems, whenever low-boiling or volatile fluids are involved, vaporization risk becomes unavoidable. This issue is especially critical when using IHF fluoroplastic chemical pumps, which are widely applied in corrosive media transfer. From real engineering practice, experienced manufacturers such as Shanghai Shangcheng Pump & Valve play a key role—not just supplying equipment, but helping avoid system-level risks before they occur. 👉 Product reference: https://www.scpv.cn/pumps/IHF-1.html 1. Structural Characteristics of IHF Pumps IHF pumps are single-stage, single-suction cantilever centrifugal pumps, designed according to international standards and combined with non-metal pump technology. Typical features include: Fluoroplastic lining (F46 / PTFE) for strong corrosion resistance Wide application across chemical, pharmaceutical, and petroch...

 Risks of Operating a ZW Self-Priming Sewage Pump at Low Liquid Levels (With Reference Link) In many wastewater applications, ZW self-priming sewage pumps often operate under low liquid level conditions—sometimes just barely maintaining suction. At first glance, everything seems fine: 👉 The pump is still running 👉 Liquid is still being discharged But in reality: 👉 Low liquid level operation is often the starting point of multiple hidden risks. Based on field experience, Shanghai Shangcheng Pump Valve has found that many performance issues and premature failures originate from prolonged low-level operation. 👉 Technical reference: 👉 https://www.scpv.cn/news/868.html 1. Deterioration of Suction Conditions Self-priming pumps rely on: 👉 Creating a vacuum in the suction line to draw liquid in () When the liquid level drops: Suction lift increases Inlet pressure decreases 👉 Result: Longer priming time Unstable suction Difficulty maintaining flow 2. Air Entrainment Becomes More Like...

 Stage-by-Stage Development of Cavitation in ISG Pipeline Centrifugal Pumps (With Reference Link) In many industrial applications, cavitation in ISG pipeline centrifugal pumps is often treated as a sudden failure. However, in reality: 👉 Cavitation develops progressively, with clear signs at each stage. If these early signals are recognized in time, serious damage can often be avoided. Based on field experience, Shanghai Shangcheng Pump Valve has observed that most severe cavitation issues actually begin with subtle early-stage symptoms that are frequently overlooked. 👉 Technical reference: 👉 https://www.scpv.cn/news/880.html 1. Initial Stage: Hidden and Hard to Detect At the beginning of cavitation: Local pressure approaches vapor pressure Small vapor bubbles start forming 👉 Characteristics: No obvious noise Stable performance Slight, occasional vibration 📌 This stage is often ignored 2. Development Stage: Noticeable Changes As operating conditions deviate further: Bubble form...

How Air Leakage in the Suction Line Affects Self-Priming Pump Performance (With Reference Link) In many real-world applications, users often encounter this issue: 👉 A self-priming pump runs, but struggles to draw liquid or performs inconsistently The first assumption is usually: 👉 The pump is underperforming However, in most cases: 👉 The real problem lies in air leakage on the suction side. Based on field experience, Shanghai Shangcheng Pump Valve has found that even minor air leaks can significantly impact the performance of self-priming pumps. 👉 Technical reference: 👉 https://www.scpv.cn/news/868.html 1. Key Principle: Self-Priming Relies on Vacuum A self-priming pump works by: Removing air from the pump and suction line Creating a vacuum Allowing atmospheric pressure to push liquid into the pump If there is air leakage: External air continuously enters the system Vacuum cannot be established or maintained 👉 Result: 👉 Loss of suction capability 2. Reduced Suction Lift Under no...

 Does Long-Term Low-Load Operation Damage Screw Pumps? The Hidden Impact on Service Life (With Reference Link) In many industrial setups, operators tend to believe: 👉 Running a screw pump under low load is “safer” 👉 Less load means less wear However, real-world data and field experience suggest otherwise: 👉 Long-term low-load operation can actually accelerate wear and reduce pump lifespan. Based on application cases, Shanghai Shangcheng Pump Valve has observed that many premature failures are not caused by overload, but by continuous off-design (low-load) operation. 👉 Technical reference: 👉 https://www.scpv.cn/news/874.html 1. Understanding the Nature of Screw Pumps Screw pumps (especially progressive cavity types) are: 👉 Positive displacement pumps They rely on: Rotor–stator sealing Stable pressure differential Continuous fluid lubrication 📌 Their efficiency depends on maintaining designed operating conditions () 2. What “Low Load” Really Means Low-load operation usually in...

 Why Diaphragm Pump Flow Rate Gradually Decreases: Structural Changes You Should Not Ignore (With Reference Link) In real-world operation, a common issue with diaphragm pumps is: 👉 The flow rate starts normal but gradually decreases over time Many users immediately suspect: Insufficient air pressure Unstable power supply However, from an engineering perspective: 👉 A gradual decline in flow is usually a sign of internal structural changes, not just operating conditions. Based on field experience, Shanghai Shangcheng Pump Valve has found that most flow reduction cases are closely related to component wear, deformation, and internal changes. 👉 Technical reference: 👉 https://www.scpv.cn/news/875.html 1. Diaphragm Fatigue and Deformation (Primary Cause) The diaphragm is the core working component: Repeated flexing over time Material fatigue Loss of elasticity 👉 Leads to: Reduced stroke volume Lower discharge per cycle 👉 Result: Gradual decrease in flow rate 2. Check Valve Wear and...

工How Isolation Sleeve Material Affects Magnetic Pump Efficiency (With Technical Reference) In magnetic drive pump applications, most users focus on: Flow rate Head Motor power But often overlook a critical component: 👉 The isolation sleeve In real-world cases, a simple material change of the isolation sleeve can lead to: Reduced efficiency Increased temperature Higher energy consumption This is not accidental. 👉 The isolation sleeve directly affects magnetic transmission efficiency. Based on field experience, Shanghai Shangcheng Pump Valve has found that improper sleeve material selection is a key factor behind efficiency loss in magnetic pumps. 👉 Technical reference: 👉 https://www.scpv.cn/news/877.html 1. Key Function: More Than Just a Barrier In a magnetic pump: 👉 Power is transmitted through a magnetic field across the isolation sleeve So the sleeve acts as: A sealing barrier A magnetic transmission medium 📌 Important insight: 👉 Any change in sleeve material directly impacts ...

 Why Mechanical Seals Fail in IH Stainless Steel Chemical Pumps: It’s Usually a Combination of Factors (With Selection Guide) In chemical pump applications, mechanical seal failure is one of the most common issues. When leakage occurs, many users immediately assume: Poor seal quality Need to replace the seal However, real engineering experience shows: 👉 Seal failure in IH stainless steel chemical pumps is rarely caused by a single factor. It is usually the result of multiple interacting conditions. Based on field cases, Shanghai Shangcheng Pump Valve has found that seal failures are often a combined effect of fluid properties, operating conditions, and installation factors. 👉 Product and selection reference: 👉 https://www.scpv.cn/pumps/ih.html 1. Key Insight: Seal Failure Is a Result, Not the Root Cause Mechanical seals are designed to: Prevent leakage Maintain stable operation But in practice: 👉 Seal failure is usually a symptom of abnormal operating conditions 2. Dry Running ...