Vertical Sealless Pump for Demanding Chemical Industry Tasks

Engineered for Uncompromising Chemical Handling

The Vertical Sealless Pump represents a paradigm shift in chemical fluid transfer technology. Engineered specifically for the most aggressive industrial environments, this pump eliminates the mechanical seal entirely, removing the primary failure point in conventional centrifugal pumps. By adopting a cantilever design with a shaft supported above the liquid, the pump operates without any bearings, bushings, or seals submerged in the fluid. This results in a truly leak-free, dry-run capable system that thrives where other pumps fail: handling acids, alkalis, solvents, and abrasive slurries with unmatched reliability. The design philosophy integrates heavy-duty thermoplastic constructions such as PP, PVDF, and UHMW-PE, providing superior corrosion resistance across a broad chemical spectrum.

Every component that contacts the pumped medium is meticulously selected to withstand chemical attack while maintaining dimensional stability. The vertical orientation allows the pump to be directly immersed into tanks, sumps, and pits, eliminating suction piping and priming issues. Its inherent ability to handle solids, fibrous matter, and entrained gases makes it the preferred choice for chemical processing plants, metal finishing lines, wastewater treatment, and pharmaceutical intermediates where seal integrity directly impacts safety, compliance, and operational continuity. With customizable immersion depths extending up to 3400 mm, this pump adapts to a vast range of installation geometries, offering consistent performance without the headaches of mechanical seal maintenance.

How Sealless Technology Redefines Safety and Efficiency

Traditional sealed pumps inevitably experience seal degradation, leading to fugitive emissions, product loss, and costly downtime. The sealless vertical pump eliminates this by separating the drive motor from the fluid path with a solid shaft and a column that houses dry bearings in the upper section. The impeller is directly coupled to the shaft, and the entire assembly relies on a rigid support structure that absorbs hydraulic and vibrational loads without any liquid-lubricated interfaces. This results in an almost maintenance-free pumping solution that can run continuously under severe conditions. Moreover, the design inherently prevents cross-contamination, which is critical in industries handling high-purity chemicals or hazardous intermediates where even micro-leakage is unacceptable.

The Critical Importance of Sealless Technology in Chemical Processing

Chemical industries operate under stringent environmental and safety regulations that demand zero leakage and minimal operator exposure to hazardous fluids. A vertical sealless pump directly addresses these requirements by providing a hermetically sealed fluid path that never contacts the atmosphere. Unlike magnetically driven pumps that rely on magnetic couplings and contain dynamic O-rings, the cantilever vertical design offers pure sealless operation with no sliding contact components in the liquid. This drastically reduces the risk of unexpected failures and the associated cleanup costs. For plants handling carcinogenic, toxic, or corrosive substances, this translates into a safer working environment and compliance with standards such as ISO 14001 and OSHA PSM requirements.

Furthermore, chemical manufacturing often involves cavitation-prone fluids, slurries with high solid content, and intermittently dry sumps. Conventional sealed pumps quickly destroy their mechanical seals under these conditions, while vertical sealless pumps thrive. The absence of a submerged bearing and seal eliminates any need for a constant liquid film or lubrication, enabling unlimited dry-running without damage. This inherent resilience reduces unplanned maintenance and extends mean time between repairs (MTBR) considerably, directly impacting the total cost of ownership. When processing acids like sulfuric or hydrochloric, the cantilever design’s ability to be built from solid thermoplastics also means uniform corrosion resistance throughout the wetted path, preventing galvanic corrosion commonly seen in metal pumps with coated internals.

The Hidden Costs of Conventional Pump Seals

Mechanical seals account for more than 70% of centrifugal pump failures in chemical service, leading to lost production, environmental penalties, and expensive repairs. A vertical sealless pump eliminates this entire failure category. By removing the seal, you also eliminate the need for flush water, buffer fluids, and complex support systems required by dual mechanical seals. This simplification reduces both capital expenditure on auxiliary equipment and ongoing operational expenses. In regions where water is scarce or where wastewater treatment costs are high, the dry-running and seal-free nature of these pumps delivers a compelling economic advantage.

Versatile Applications Across Chemical Industries

The vertical sealless pump is not a one-size-fits-all product; it is a platform engineered to meet the diverse demands of modern chemical facilities. From neat acid transfer to dirty sump drainage, its performance envelope covers flow rates up to 1,000 LPM and heads reaching 35 meters. The pump’s ability to handle solid-laden liquids and abrasive slurries stems from optional vortex or semi-open impellers, which prevent clogging even when pumping stringy materials or crystalline solids. This capability opens a wide spectrum of application possibilities that would otherwise require multiple specialized pump technologies, thereby simplifying inventory and standardizing maintenance procedures across the plant.

In pharmaceutical and fine chemical production, the pump’s smooth, non-metallic surfaces and sealless construction prevent contamination, making it suitable for high-purity solvent transfers and reactor feed applications. Its gentle pumping action also minimizes shear forces on sensitive products like polymer emulsions or biological reagents. The opportunity to use the same pump family for both corrosive chemicals and waste sludge simplifies sparing and reduces learning curves for operators. The robust bearing housing, located outside the tank, permits continuous operation even when the tank is nearly empty, solving a persistent challenge in batch processing where heel management is critical.

Industry-Specific Uses

• Chemical Processing: Transferring aggressive liquids such as sulfuric acid, nitric acid, caustic soda, and hydrofluoric acid in continuous flow reactors, storage tanks, and neutralization systems. The thermoplastic construction resists etching and embrittlement, ensuring long-term dimension stability.
• Metal Finishing: Recirculating acidic plating baths (chrome, nickel, zinc) and alkaline cleaner solutions. The pump’s vortex impeller handles suspended metallic fines without clogging, maintaining consistent flow to spraying bars and immersion racks.
• Wastewater Treatment: Pumping acidic or alkaline effluents laden with solids, sludge, and fibrous materials from equalization basins to filter presses or clarifiers. Dry-run ability allows the pump to survive sudden drops in sump level during batch emptying.
• Mining and Mineral Processing:
• Bulk Chemical Storage and Distribution: Unloading tankers and transferring chemicals from storage tanks to day tanks or production lines. The vertical design minimizes footprint in bunded areas and eliminates the risk of seal leakage during intermittent operation when lines are drained and primed repeatedly.
• Steel Pickling and Galvanizing: Circulating hydrochloric or sulfuric acid through pickling tanks. The pump’s solid PVDF construction withstands continuous exposure to hot acids and fumes, while the vortex impeller handles scale particles without impacting flow stability.
• Pharmaceutical Intermediates: Transferring high-purity solvents and acidic reagents in API and fine chemical production. The sealless, non-metallic design prevents metal ion contamination, ensuring product purity and compliance with GMP guidelines.
• Photovoltaic Cell Manufacturing: Handling aggressive wet etching chemicals such as hydrofluoric acid and potassium hydroxide in texturing and cleaning baths. The pump's consistent, pulse-free delivery preserves surface integrity on delicate wafers.
• Chemical Injection in Refineries: Dosing amines, corrosion inhibitors, and demulsifiers into hydrocarbon streams. The vertical pump eliminates fugitive emissions and provides precise, repeatable flow control essential for process optimization and HSE compliance.
• Biofuel and Ethanol Plants: Pumping acidic process intermediates and caustic cleaning solutions through CIP systems. The thermoplastic pump resists corrosion from fermentation byproducts and offers rapid flushability between batches.

Across these applications, the vertical sealless pump consistently outperforms traditional sealed centrifugal pumps by eliminating seal-related downtime, reducing ancillary equipment costs, and providing a predictable lifetime. Its modularity allows the same pump platform to be configured with different materials and impeller types, enabling a single source for multiple chemical handling needs. This adaptability reduces engineering time and simplifies maintenance documentation, ultimately accelerating project timelines and improving plant reliability indices.

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Outstanding Key Features

The vertical sealless pump brings together a suite of features meticulously designed to address the real-world challenges of chemical handling. Each feature is the result of decades of field experience and a deep understanding of how corrosion, abrasion, and operational abuse conspire to degrade pump performance. The construction philosophy leverages the natural advantages of engineering thermoplastics: zero corrosion, low surface roughness, and resistance to chemical attack. When combined with an intelligent hydraulics design, the pump achieves efficiencies that rival metallic sealed pumps while delivering an order-of-magnitude improvement in mean time between failure. From the large-diameter solid shaft that transmits torque without whip to the oversized dry bearings isolated from the fluid, every element contributes to a system that can be installed and essentially forgotten, requiring only periodic motor checks and visual inspections.

Beyond corrosion resistance, the pump excels in operational flexibility. Its ability to handle up to 30% entrained gas and to self-ventilate eliminates vapor locking common in horizontal centrifugal pumps. The optional vapor seal design prevents corrosive fumes from migrating up the column and attacking the motor, extending drive component life even in extremely aggressive airborne environments. The integration of various impeller styles – including closed, semi-open, and vortex – enables the same pump to be configured for clean liquids, solids up to 50 mm, or fibrous slurries. This versatility reduces the need for multiple pump types and simplifies training and maintenance across the facility.

Designed for Relentless Performance

• 100% Sealless Design: There are absolutely no mechanical seals, lip seals, or dynamic O-rings submerged in the pumped fluid. The fluid path is completely encapsulated, eliminating leakage and ensuring compliance with the most stringent environmental regulations.
• Unlimited Dry-Run Capability: Since no liquid-lubricated bearings exist in the fluid zone, the pump can run indefinitely without liquid supply – perfect for sump-emptying, batch transfers, and emergency drainage without risk of catastrophic failure.
• Solid Thermoplastic Construction: Available in PP (polypropylene), PVDF (polyvinylidene fluoride), or UHMW-PE (ultra-high molecular weight polyethylene) for the wetted components. These materials resist pH extremes, organic solvents, and halogens without protective coatings that can crack or peel.
• >Solid Shaft and Dry External Bearings: The shaft is fully isolated from the fluid by a column sleeve, with heavy-duty anti-friction bearings located in the above-liquid head assembly. This keeps the bearings dry and lubricated with grease, providing a service life exceeding 25,000 hours without needing replacement.
• Vortex and Semi-Open Impeller Options: For fluids containing solids up to 50 mm or fibrous matter, the vortex impeller creates a swirling motion that conveys material without direct impeller contact, eliminating clogging. The semi-open impeller offers higher efficiencies for mildly contaminated liquids while still passing small solids and maintaining suction performance.
• Vapor and Fume Protection: An optional vapor seal and purge connection prevent corrosive fumes from migrating up the column and damaging the motor windings. This feature is critical in applications involving hydrochloric or nitric acid, where airborne acid mist causes severe corrosion of adjacent equipment.
• High-Efficiency Hydraulics: Computer-modeled impeller and volute geometries deliver hydraulic efficiencies up to 72%, minimizing energy consumption and motor size. The optimized inlet design reduces NPSH requirements, enabling the pump to operate reliably even with boiling or near-boiling liquids.
• Interchangeable Materials and Linings: The modular design allows wetted components to be swapped between PP, PVDF, and UHMW-PE without altering the bearing frame or motor mount. This interchangeability streamlines spares management and allows a pump to be re-purposed for a different chemical service in minutes.
• Simple Maintenance Without Special Tools: The entire impeller and column assembly can be removed from the tank without dismantling the motor or pipe connections. All fasteners are external and accessible, cutting routine inspection time to under 30 minutes and keeping plant downtime negligible.

Together, these features provide a robust pumping solution that directly reduces lifetime operational costs. By eliminating seal replacements, flush water usage, and unplanned maintenance events, the vertical sealless pump often achieves a payback period of less than 12 months compared to traditional sealed pumps in aggressive chemical service. Its inherent simplicity makes it the ideal choice for any facility prioritizing reliability, safety, and low environmental footprint.

Thorough Technical Specifications

The vertical sealless pump is engineered for conditions where precise performance and absolute reliability intersect. Every specification has been verified through extensive laboratory testing and field trials in chemical plants around the world. The pump’s hydraulic envelope covers a broad spectrum of chemical transfer tasks, while its structural design ensures stable operation even under variable suction conditions. By selecting the correct material and impeller type from the detailed specifications below, engineers can ensure optimal performance, maximum service life, and full compatibility with the most challenging chemical processes. The following table-style presentation of technical parameters provides the essential data needed for front-end engineering design (FEED) and equipment specification.

The specifications are backed by rigorous quality control that includes hydrostatic pressure testing at 1.5 times the design pressure, dynamic balancing of the impeller to ISO 1940 Grade G6.3, and full performance curve verification on each pump. All pumps are factory-tested to ensure they meet the published head-capacity characteristics before shipment, giving the end-user immediate confidence in installation and commissioning.

Performance and Build Parameters

• Maximum Flow Rate: Up to 1,000 liters per minute (264 GPM), enabling rapid transfers in bulk chemical handling and high-capacity circulation loops. The wide flow range allows a single pump model to serve multiple process duties by adjusting motor speed or impeller diameter.
• Maximum Total Head: 35 meters (115 feet), sufficient to overcome static and friction losses in multi-story plants, through filters, heat exchangers, and long piping runs without staging additional pumps.
• Immersion Depths Available: Standard lengths from 600 mm to 3400 mm, measured from the mounting flange to the suction inlet. Custom depths can be manufactured to suit unusual tank geometries, ensuring the pump inlet always remains submerged beneath the minimum liquid level.
• Solids Handling Capability: Vortex impeller models pass spherical solids up to 50 mm diameter; semi-open impellers pass up to 20 mm. This makes the pump ideal for reactor slurry recirculation and sump drainage where debris is inevitable.
• Operating Temperature Range: PP up to 80°C, PVDF up to 110°C, UHMW-PE up to 60°C continuously. The selection of material must be chosen to match the chemical concentration and temperature, ensuring the pump maintains its mechanical integrity and does not undergo thermal deformation over years of service.
• Motor Power Range: 0.5 HP to 15 HP (0.37 kW to 11 kW) in standard TEFC or explosion-proof enclosures. Motors are IEC or NEMA frame compatible and can be supplied for 50 Hz or 60 Hz supplies, with voltage options to match plant electrical infrastructure.
• Shaft and Column Construction: Solid metallic shaft (SS304 or SS316) with thick-walled thermoplastic column sleeve encapsulating the shaft and preventing any fluid contact. The column is designed to absorb hydraulic thrust without deflection, ensuring vibration-free operation even at maximum immersion lengths.
• Discharge Connection Standard: Flanged or threaded discharge connections ranging from 25 mm (1 inch) to 80 mm (3 inches), made from the same thermoplastic material as the pump body for perfect chemical compatibility and easy connection to existing plant piping.
• Bearing Life (L10): Over 25,000 hours under rated operating conditions. The large-diameter bearings are grease-lubricated and isolated from the chemical environment, with easily accessible grease fittings on the bearing housing for periodic replenishment without disassembly.

These technical specifications reflect a conservative engineering approach that prioritizes safety margins and long-term performance over marginal cost savings. By adhering to these proven limits, process engineers can confidently integrate the pump into their P&IDs knowing that the hydraulic and mechanical design has been validated across thousands of installations handling similar aggressive chemicals.

Why Choose HIS Pumps and Systems

HIS Pumps and Systems has built its reputation on delivering highly engineered pumping solutions that perform reliably in the world's most demanding chemical environments. Unlike general-purpose pump suppliers who offer a wide catalog of unrelated products, our expertise is concentrated specifically on sealless and thermoplastic pump technologies. This focus enables us to offer a depth of application knowledge that translates into accurate pump selections, faster troubleshooting, and lower lifecycle costs for our customers. Every vertical sealless pump we manufacture undergoes comprehensive quality checks, including dimensional inspections, material certification, and hydraulic performance testing to ensure it meets the specified operating point before leaving our facility.

Our commitment extends well beyond the initial sale and installation. We maintain a substantial inventory of finished pumps and spare parts, enabling same-day or next-day dispatch for most standard configurations. Our field service engineers are available for commissioning, troubleshooting, and on-site training, ensuring your operations team understands how to achieve maximum reliability from our equipment. We also provide complete material certification, chemical resistance guides, and installation drawings, streamlining the integration of our pumps into your plant's engineering documentation and management-of-change procedures.

The HIS Advantage

• Unmatched Application Expertise: Our team possesses decades of combined experience in chemical pump selection, material compatibility, and system design. We do not just sell a pump; we analyze your complete fluid path to identify potential issues like NPSH limitations, air entrainment risks, and pipe strain considerations before they become problems.
• Rigorous Factory Testing: Every vertical sealless pump is hydrostatically tested and run on a calibrated test loop. We record flow, head, power consumption, and vibration signatures to establish a baseline. This documentation is provided with the pump, enabling predictive maintenance programs and future troubleshooting.
• Extensive Spares Inventory: We stock impellers, columns, bearing assemblies, and complete pump heads for all standard models. This level of readiness means that even in the unlikely event of a component failure, your downtime is measured in hours, not weeks.
• Custom Engineering Capabilities: For unique applications, our engineering department can design modified impeller geometries, non-standard immersion lengths, or special motor mountings. We treat every order as an opportunity to engineer a solution, not just ship a catalog number.
• Complete Chemical Resistance Database: We maintain an exhaustive database correlating hundreds of chemicals with our thermoplastic materials, documenting acceptable concentration and temperature limits. This data-driven approach eliminates guesswork and ensures the pump you receive will handle your specific chemical process.
• Global Support and Rapid Response: With a network of experienced representatives and engineers, we provide timely technical support, commissioning assistance, and troubleshooting guidance. Our responsive communication channels ensure you are never left waiting for an answer when your process is at stake.
• Value-Engineered Solutions: We continuously refine our designs using feedback from the field. Improvements in bearing sealing, column rigidity, and hydraulic efficiency are systematically incorporated, meaning our customers benefit from a constantly evolving product that reflects the latest industrial best practices.

Choosing HIS Pumps and Systems means partnering with an organization that treats your chemical handling challenges as its own. Our dedication to engineering excellence, responsive service, and comprehensive aftermarket support makes us the preferred supplier for chemical plants seeking to maximize safety, uptime, and total cost of ownership with vertical sealless pump technology.

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Comprehensive Material Compatibility for Aggressive Chemicals

Material selection is the single most critical decision in specifying a pump for chemical service. A pump constructed from an incompatible material will fail prematurely through corrosion, swelling, or embrittlement, regardless of its mechanical design. Our vertical sealless pump platform provides three distinct thermoplastic material families, each offering a unique balance of chemical resistance, temperature capability, and cost-effectiveness. These materials were chosen not arbitrarily but based on decades of field data correlating chemical concentration, exposure temperature, and mechanical load. By understanding the specific material properties and their compatibility boundaries, process engineers can select a pump that will deliver reliable performance for years without requiring liner replacements or weld repairs.

The molecular structure of each thermoplastic determines its resistance to specific chemical attack mechanisms. PP (polypropylene) relies on its hydrophobic hydrocarbon backbone to resist aqueous solutions of acids, bases, and salts, but it is susceptible to swelling in organic solvents. PVDF (polyvinylidene fluoride) introduces fluorine atoms into the polymer chain, dramatically improving its resistance to halogens, solvents, and oxidizers, while also raising the maximum operating temperature. UHMW-PE (ultra-high molecular weight polyethylene) achieves its performance through extremely long polymer chains that create a dense, abrasion-resistant surface with excellent chemical inertness. Selecting the optimal material requires careful consideration of all chemical species present, including minor constituents and potential trace impurities that may accumulate in recirculating systems.

Material Options and Chemical Resistance Profiles

• Polypropylene (PP) Construction: PP offers excellent resistance to a wide range of aqueous acids (sulfuric, hydrochloric, nitric at moderate concentrations), caustic solutions, and saline water. It is cost-effective and lightweight, making it the most common choice for general chemical transfer where solvents and strong oxidizers are absent. Its continuous operating limit of 80°C accommodates most process and washing temperatures without deformation.
• PVDF (Polyvinylidene Fluoride) Construction: PVDF is the premium choice when handling strong oxidizing acids (concentrated nitric, sulfuric), halogens (bromine, chlorine), aromatic solvents, and hot aggressive media. Its fluoropolymer backbone provides exceptional chemical resistance and a continuous temperature rating up to 110°C. PVDF maintains its mechanical strength and stiffness at elevated temperatures, preventing creep and distortion under load.
• UHMW-PE (Ultra-High Molecular Weight Polyethylene) Construction: UHMW-PE is unsurpassed for abrasive slurries and applications where impact toughness and low coefficient of friction are required. It resists many acids and bases while providing near-zero moisture absorption. Its continuous temperature limit of 60°C restricts its use in hot processes, but for room-temperature abrasive duties, its wear life far exceeds other thermoplastics.
• Chemical Compatibility Verification: Each pump material selection is cross-referenced against our proprietary chemical resistance database that accounts for concentration, temperature, and stress. For mixtures, blend compatibility is evaluated by analyzing the most aggressive component and considering synergistic effects, ensuring no hidden vulnerability.
• Metallic Shaft Encapsulation: The internal shaft is made from SS304 or SS316 and is completely isolated from the fluid by a thick thermoplastic column sleeve. This encapsulation eliminates any metal contact with the chemical, preventing corrosion and preserving shaft strength. The column sleeve also acts as a secondary containment in the unlikely event of a crack or defect.
• Temperature-Pressure Interrelationship: As temperature rises, the pressure-holding capability of thermoplastics decreases. Our engineering guidelines de-rate the pressure rating linearly above 40°C for PP and 70°C for PVDF, ensuring the pump casing and column never operate beyond safe stress limits. This prevents catastrophic rupture under upset conditions.
• Abrasion vs. Chemical Attack: In slurry services, wear is a combination of chemical and mechanical factors. UHMW-PE provides the best resistance to sliding abrasion, while PVDF resists chemical erosion better in high-velocity acidic streams. The choice is made by analyzing particle size, hardness, and velocity to predict service life accurately.

By aligning the chemical composition of your process fluid with the appropriate thermoplastic material, the vertical sealless pump delivers a maintenance interval that is dictated by motor bearing regreasing rather than any degradation of the wetted components. This materials-first approach prevents the rapid failure modes that plague metallic pumps in chemical duty, providing peace of mind and a predictable, safe operation for the entire plant lifecycle.

Vertical Sealless Pump Selection Guide

Choosing the correct vertical sealless pump configuration requires a systematic evaluation of the hydraulic duty, chemical nature, solids content, and installation constraints. The following guide distills our application engineering experience into a logical sequence of decision points. By methodically working through each criterion, you will arrive at a pump specification that balances performance, longevity, and cost. Our technical team can assist at any stage, but this guide provides the foundational understanding needed to initiate an informed discussion.

Proper pump selection is critical because an oversized pump wastes energy and accelerates wear, while an undersized pump fails to meet process requirements and may cavitate. The sealless construction inherently tolerates a wider operating window than sealed pumps, but precision in specifying flow, head, and immersion depth remains essential for achieving maximum efficiency and longest bearing life. Use the following criteria as a checklist to compile a complete data sheet for quotation.

Step-by-Step Selection Criteria

• Define the Hydraulic Duty Point: Determine the required flow rate (LPM or GPM) and total dynamic head (meters or feet) at the pump discharge. Account for static lift, friction losses in pipes, fittings, and any downstream equipment such as filters or heat exchangers. Select a pump whose best efficiency point (BEP) is within 80-110% of the specified flow to ensure stable, vibration-free operation.
• Characterize the Fluid Chemistry: List all chemical components, their concentrations (by weight %), and the operating temperature range. Identify trace constituents that could cause stress cracking or catalyze degradation. Use this list to select the correct wetted material: PP for general acids/alkalis up to 80°C, PVDF for oxidizers, halogens, and solvents up to 110°C, or UHMW-PE for abrasive, ambient-temperature slurries.
• Evaluate Solids and Viscosity: Measure the concentration, particle size, and hardness of any suspended solids. For solids larger than 20 mm or fibrous materials, choose the vortex impeller. If the fluid contains up to 20 mm solids and you require higher efficiency, choose the semi-open impeller. For clean, low-viscosity liquids, , choose the closed impeller for maximum hydraulic efficiency. This impeller type offers the highest efficiency and stable head curve, but requires clean fluids free of particulate contamination that could cause clogging.
• Determine Immersion Depth: Measure the vertical distance from the pump mounting flange to the lowest expected liquid level in the tank or sump. Select an immersion depth that keeps the impeller submerged with at least 200 mm of submergence at all times to prevent vortex formation and air ingestion. For tanks with varying levels, choose the deepest practical immersion to minimize the risk of running dry during drawdowns.
• Motor Selection and Enclosure: Choose motor power based on the absorbed power at the duty point plus a 15-20% safety margin. For flammable or explosive atmospheres, specify explosion-proof (Ex d) or increased safety (Ex e) motors certified to ATEX or IECEx. TEFC enclosures are standard for general chemical environments, but for outdoor installations, ensure IP56 protection against dust and water ingress.
• Mounting and Tank Interface: Define the tank top geometry and available nozzle size. Standard mounting plates are designed to ANSI or DIN flange dimensions. Ensure the pump’s baseplate is rigid enough to dampen vibration and that the tank itself can support the dynamic loads. For open sumps, a fabricated steel mounting bracket may be required to span the opening securely.
• Vapor Handling and Purge: If the pumped liquid generates corrosive fumes (HCl, HF, HNO3), incorporate a vapor seal and a clean air or nitrogen purge to the column. This prevents acid mist from attacking the motor and bearing housing. Purging also cools the shaft and column, extending the life of the dry bearings in high-temperature applications.
• Consider Variable Speed Operation: For processes requiring flow variation, pairing the pump with a variable frequency drive (VFD) can significantly reduce energy consumption and provide soft starts. The sealless design tolerates reduced speeds without minimum flow concerns, allowing turndown ratios of 3:1 or more. Ensure the motor is inverter-rated and the pump operates away from resonant frequencies identified during commissioning.
• Validate NPSH and Cavitation Risks: Calculate the net positive suction head available (NPSHa) and compare it to the pump’s NPSH required (NPSHr) at the duty flow. For hot liquids near their boiling point, provide a safety margin of at least 1 meter. The vertical inlet design inherently assists NPSH by providing a positive static head of liquid above the impeller eye, making the pump forgiving in suction-limited installations.
• Plan for Maintenance Access: Although the pump requires minimal maintenance, ensure sufficient overhead clearance for lifting the complete pump assembly from the tank. A davit crane or hoist ring simplifies removal for annual bearing inspection. Document the installed depth and pipe connections to facilitate rapid reinstallation after servicing without lengthy alignment procedures.

Following this structured selection process ensures that the vertical sealless pump you install will deliver the performance and reliability your chemical process demands. With the pump properly sized, materials matched to the fluid chemistry, and installation details addressed, you can expect a service life exceeding a decade with only routine bearing lubrication. For assistance at any stage, our application engineers are ready to help you finalize the optimal specification and provide a firm quotation.