VS4 Series API 610 Vertical Chemical Centrifugal Cantilever Pump

API 610 Type VS4 vertical suspended, cantilevered submersible pump with the discharge outlet located within the pump column.

The pump and motor are connected by a flexible coupling and supported by mounting flanges.

• Media:

  Solids and corrosive liquids, chemical processes, sewage, flammable and explosive liquids

• Process:

  Up to 800 cubic meters per hour (3,520 gallons per minute)

• Head:

  Up to 125 meters (410 feet)

• Temperature:

  -40 ~ 500℃ (-40–932°F)

• Pressure:

  Up to 20 bar/50 bar (290/720 psi)

• Speed:

  /

• API type code:

  API 610, 11th Edition, VS4 / VS5

Product Attributes:

Maximum head: >150 meters

Maximum flow rate: >400 L/min

Drive Type: Motor

Impeller inlet type: single-suction pump

Pump shaft position: vertical pump

Impeller type: Closed

Transport packaging: wooden crate

Specification: API 610 Standard

Place of Origin: Dalian, Liaoning Province, China

Size: DN40–400

Head: approximately 200 meters

Flow rate: ~400 cubic meters/hour

Temperature: -20 to 300 degrees Celsius

Pressure: ~5 MPa

Application:

The KY-type pump is a vertical, single-stage, single-suction, long-shaft submersible pump, suitable for various wastewater transfer applications in power plants, chemical plants, and sewage treatment plants.

It is mainly used for

1. Thermal Power Plant

2. Chemical plant

3. Wastewater Treatment Plant

4. Steel factors, steel rolling mill

5. Paper mill

6. Cement plant

Performance range:

1. Capacity Q 2–400 m³/h

2. Head H 5–100 meters

3. Operating temperature: T -20~ +200°C

Structure:

1. A safe and reliable connecting shaft structure.

2. The rotor assembly employs multi-point support to ensure safe and reliable pump operation.

3. Sliding bearings employ either external lubrication or self-lubrication.

4. When the pump is started, the impeller is already fully immersed in the fluid, so it can be easily started without the need for priming.

5. A double-support bearing housing is employed (for diameters greater than 80 mm). Due to the small radial forces on the rotor components, minimal shaft deflection, and low wear and loss in the sliding bearings, the service life is extended.

6. Viewed from the motor end, the pump rotates clockwise.

Material:
Carbon steel; chrome-plated steel; austenitic stainless steel; duplex stainless steel; titanium and titanium alloys; Hastelloy C-276 and other specialty materials; the specific material selected shall be determined based on customer requirements.

API 610 VS4 Vertical Chemical Centrifugal Cantilever Pump

Product Overview:

• API 610 Type VS4 vertical suspended, cantilevered submersible pump with the discharge outlet located within the pump column.
• The pump and motor are connected by a flexible coupling and supported by mounting flanges.

Features:

• Independent discharge pipe, no pressurized liquid leakage, and no shaft seal required.
• Submersible impeller and volute design eliminates the need for priming or venting at startup.
• A reliable shaft design ensures stable pump operation.
• A suction tube can be used when a deeper installation is required.
• A heating jacket is used when conveying high-temperature molten materials.
• Open impellers are suitable for liquids containing particles.

Application:

• Used as a mud pump for conveying solids and corrosive liquids.
• Rolling mill.
• Chemical process.
• Wastewater treatment.
• Flammable and explosive liquid transfer pump.

API 610 is the internationally recognized standard for centrifugal pumps used in the petroleum, petrochemical, and natural gas industries, and “VS4” is a specific pump type defined within that standard.

The following is a detailed introduction to the API 610 VS4 pump. I will systematically outline its definition, design features, and application scenarios, and compare it with other common API pump types.

API 610 VS4 Submersible Long-Shaft Centrifugal Pump

Place of origin: Dalian, Liaoning Province, China

Delivery period: three months

Supply capacity: ample supply

Kehuan Pump has achieved comprehensive breakthroughs in addressing the existing technical bottlenecks of magnetic drive pumps, covering operating conditions such as high power, high temperature, slurry-containing media, easy vaporization, and high melting points.
Design Framework: We employ advanced European hydraulic modeling;
Designed in accordance with API 685, the American Petroleum Institute standard.
High-standard materials are employed: permanent magnets (Sm2Co17, operating temperature range: −196 to 450°C), sliding bearings (SSIC), sealing housings (HC-276), rolling bearings (SKF/NSK), couplings (Wuxi Chuangming/Germany’s KTR), and electric motors (Nanyang/Jiamusi).

1. Core Performance Parameters
The OCV series pumps cover a range of parameters that meet the typical operational requirements of the refining, oil and gas production, and petrochemical industries.

Parameters Item OCV Series (Standard Type) OCVSF Series (Sulfur Melting Special Type)
The flow rate can range from a maximum of 750 cubic meters per hour to a minimum of 200 cubic meters per hour.
Lifting height can reach 280 meters, with a maximum lifting height of 100 meters.
Maximum pressure: 40 bar, 40 bar
Applicable temperature: -46°C to 260°C -46°C to 260°C
Outlet size: 50 to 200 mm, 50 to 100 mm
Please note that data on third-party websites may differ slightly from official figures (for example, the nose height may be listed as 920 feet/280 meters or 880 feet/268 meters, and the maximum temperature limit may be shown as 205°C or 260°C). We recommend referring to the data on the Sulzer official website (sulzer.com) as the primary source.

2. Core Design Features
Parts Commonality with OH2 Pumps: This is the most significant economic advantage of the Sulzer VS4 pump. Its pump casing, pump cover, wear parts, and impeller are fully interchangeable with those of more than 10,000 in-service OHH and OHHL (API 610 OH2) horizontal pumps, substantially reducing customers’ spare-parts inventory costs.

Strictly comply with API standards:

Fully compliant with the latest edition of API 610, the bearing span design ensures that the first critical speed is higher than the operating speed.

The optional seal chamber complies with the requirements of API 610 Table 7 and is compatible with mechanical seals conforming to API 682.

Extensive material options: A wide range of material grades commonly specified in API 610, such as S-6, S-8, A-8, D-1, and D-2, are available to meet diverse corrosive service conditions.

Bearing and Lubrication System:

Standard thrust bearings are oil-lubricated and equipped with fan cooling; grease lubrication or oil-mist lubrication is available as an option.

The intermediate shaft bearing is standardly equipped with a self-lubricating carbon-graphite bearing; alternatively, grease lubrication or an external flushing system can be specified.

Installation method: The standard configuration includes a rectangular epoxy-coated carbon steel mounting plate; for pressure vessel installation, a blind flange mounting plate compliant with ASME B16.47 may also be provided.

3. Special Model: OCVSF Sulfur Melt Pump
Sulzer has developed an OCVSF variant on the OCV standard platform for the conveyance of molten sulfur, with the following key features:

Full jacket design: Each upright column and discharge pipeline is equipped with a steam jacket to ensure that the sulfur remains in a molten state throughout the entire conveying path.

Special impeller: A semi-open impeller with free-discharge characteristics is employed to prevent sulfur solidification and blockage.

Materials and Structure: The pump is also available with materials such as S-6, A-8, D-1, and D-2, and its discharge piping is capable of withstanding nozzle loads up to three times the values specified in API 610.

We hope the above parameters will assist you in your selection process. Should you require application case studies under specific operating conditions, we would be happy to discuss them further.

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1. Core Definitions and Basic Concepts
API 610: American Petroleum Institute standard, formally titled “Centrifugal Pumps for Petroleum, Petrochemical, and Natural Gas Industries.” This standard specifies the minimum requirements for the design, materials, manufacturing, and testing of centrifugal pumps used under severe service conditions, thereby ensuring high reliability, long-term operational performance, and safety.

VS4: In the API 610 standard, “VS” stands for “vertically suspended,” while the numeral “4” indicates the specific structural type. VS4 is commonly referred to as a “submersible vertical pump” or a “wet-well vertical pump.”

Key feature: In the VS4 pump, the entire pump assembly, including the motor, is located above the liquid level, while the impeller immersed in the liquid is driven by a long drive shaft. The pump’s “casing” section—comprising the impeller and diffuser—is mounted inside a separate vessel or pipeline known as a “sump,” which is then inserted into the storage tank or reservoir.

2. Typical Structural Breakdown of the VS4 Pump
Top-tier components:

Drive motor: Standard horizontal motor, mounted on the top flange or frame for easy maintenance.

Thrust Bearing Assembly: This assembly withstands the axial forces generated during pump operation as well as the rotor’s self-weight. It typically employs a Kingsbury-type or similar thrust bearing lubricated with oil, making it one of the most critical components of the VS4.

Shaft seals: Single- or double-end mechanical seals are typically used and installed in the dry area above the liquid level to facilitate inspection, maintenance, and adjustment and setting of the sealing system.

Drive Shaft System:

Long transmission shaft: connects the motor to the impeller, with lengths ranging from several meters to dozens of meters. The shaft consists of multiple sections joined by rigid couplings and is equipped with intermediate supports (alignment supports).

Intermediate bearings: These are arranged longitudinally along the shaft to prevent lateral (swinging) vibrations. Such bearings must be lubricated and cooled by the fluid being conveyed, thus placing certain requirements on the fluid’s lubricity (they are not suitable for media containing excessive solid particles or with very poor lubricity).

Bottom pumping assembly (inside the caisson):

Impeller: Typically designed as single-stage or multi-stage to meet the required head requirements.

Volute/Pump Casing: Converts the kinetic energy of the fluid into pressure energy. In the VS4, this component features a compact design and is submersible.

Suction nozzle/filter: guides the liquid smoothly into the impeller.

Pump well: a vertical cylindrical structure used to encase and support the pump’s bottom assembly and drive shaft. It is fixed to the bottom or side wall of a tank or vessel, providing a passage for liquid to enter the pump while protecting the internal components.

3. Core Design Features and Advantages
Space-saving design: The motor and all major maintenance points are located above the liquid level, thereby eliminating the need for valuable tank farm area or pit space. This makes it ideally suited for applications such as storage tank areas, cooling tower basins, and wastewater treatment ponds.

Motorless submersible design: This motor is a standard horizontal air-cooled unit that offers high reliability, low cost, and simple maintenance, effectively eliminating the sealing and insulation issues that can arise with submersible pumps or wet-rotor motors.

Excellent cavitation performance: Since the impeller is fully submerged in the liquid, the net positive suction head available (NPSHa) is very high, virtually eliminating concerns about cavitation.

Easy maintenance: When servicing the mechanical seal, bearings, and motor, there is no need to drain the tank or reservoir—simply lift out the entire pump assembly, from the motor to the impeller. This is a key advantage over submersible pumps and certain horizontal pumps.

Rigid Design: Complies with API 610 standards for rigid rotors, high-grade bearings, and shaft deflection, ensuring stable operation.

4. Main Application Scenarios
The VS4 pump is the preferred solution for the following applications:

Tank farms at refineries and chemical plants: used for the transfer, decanting, and circulation of crude oil, refined petroleum products, and chemical feedstocks within the tank farm area.

Cooling water system: Circulating water pumps for large cooling towers.

Stormwater Drainage and Wastewater Treatment: Upgrade and retrofit the plant’s stormwater monitoring ponds and emergency spill containment ponds to ensure compliance with discharge standards.

Seawater level: Seawater intake from desalination plants or coastal industrial facilities.

Low-pressure boiler feedwater: feedwater pump for the deaerator water tank.

Sulzer’s OCV series sump pumps comply with API 610 VS4 standard. These pumps are vertical, cantilevered, single-stage, submersible units specifically designed for transferring liquids from oil collection tanks, storage tanks, or drain pits.

🔧 Core Structural Features
The structural design of OCV pumps centers on high reliability, ease of maintenance, and adaptability to special media:

Compliance with International Standards: Designed in strict accordance with the latest edition of API 610 (VS4) to ensure reliable operation under harsh service conditions.

Highly Interchangeable Design: The pump cover, wear parts, and impeller are universally interchangeable with more than 10,000 Sulzer API 610 OH2 pumps, including the OHH and OHHL series, thereby reducing spare-parts inventory costs.

Robust rotor and bearing system:

Heavy-duty shafts and bearing spans in accordance with API 610 standards: Ensure that the first critical speed of the shaft system is higher than the operating speed to reduce vibration.

Lubrication of the intermediate bearing: The intermediate bearing is lubricated using the pumped medium, which is suitable for cleaning fluids.

A variety of thrust bearing lubrication options are available: standard thrust bearings are lubricated with oil and cooled by fans, with optional grease lubrication or oil-mist lubrication to meet diverse operating conditions.

Customized design for special operating conditions:

Steam Jacket (OCVSF Type): This model is equipped with a steam jacket and is specifically designed for media such as molten sulfur that require heat tracing to prevent solidification.

A wide range of material options: We offer various material grades specified in API 610, including S-6, S-8, A-8, D-1, and D-2, to accommodate different corrosive or highly corrosive service conditions.

Flexible installation options: comes with a rectangular epoxy-coated steel mounting plate (suitable for sumps or tanks) or an optional B16.47 blind flange mounting plate (suitable for pressure vessel installation).

📊 Key Performance Parameters
Supplementary Explanation of the Performance Parameter Ranges for Sulzer OCV (VS4)
The maximum flow rate can reach 750 cubic meters per hour (2,200 gallons per minute), which falls within the medium-flow range.
The maximum head can reach 280 meters (880 feet), and a single-stage design is sufficient to achieve medium-to-high heads.
The maximum working pressure can reach 40 bar (580 psi), making it suitable for medium-pressure applications.
It operates over a wide temperature range, from -46°C to 260°C (-50°F to 500°F), making it suitable for a variety of industrial media.
The outlet size ranges from 50 to 200 millimeters (2 to 8 inches), with a variety of nominal diameters available.
🏭 Main Application Industries
Thanks to its reliable vertical submersible design and ability to handle special media, Sulzer OCV (VS4) pumps are primarily used in the following applications:

Oil and Natural Gas:

Oil-water pits/drainage sumps: Used to collect and discharge oil-containing wastewater or stormwater within the premises of refineries and chemical plants.

Lubricant Supply: Serves as the oil supply pump for the lubrication circulation system.

Tank farm material transfer: Use a foot pump in the tank farm to draw the collected liquid from the storage tanks.

Chemistry and Special Processes:

Sulfur Melting and Conveying (OCVSF Model): Specifically designed for sulfur shaping or conveying processes that require heat tracing and thermal insulation.

We hope the information provided above on the Sulzer VS4 pump has been helpful. If you would like to compare its selection criteria with those of the VS1 (closed-type axial-flow pump) or the VS6 (multistage bladder pump), please feel free to contact us again at any time.
Structural Features and Application Industries of the Vossloh VS4 Pump
I have read 8 webpages.
Flowserve pumps that comply with the API 610 VS4 standard are primarily based on the Worthington® ECPJ series of sump pumps. This pump is a single-stage, vertical, spool-type submersible pump specifically designed for transferring process fluids from catch tanks, storage tanks, sumps, or open-top tanks.

🔧 Core Structural Features
The structural design of ECPJ pumps centers on high reliability, modular customization, and adaptability to harsh operating conditions:

Compliance with International Standards: The design is rigorously in accordance with the latest editions of ISO 13709 and API 610 (VS4), while the seal chamber and flushing scheme also comply with API 682 (ISO 21049), thereby ensuring the equipment’s reliability under harsh operating conditions.

Modular Design and Multiple Hydraulic Configurations: Based on a modular design system, we offer 45 standard sizes with a maximum installation length of 8 meters. In addition, we provide a variety of impeller hydraulic designs that comply with API 610 standards and can be customized to meet diverse operating conditions.

ECPJ-R: Closed Impeller

ECPJ-O: Semi-open Impeller

ECPJ-F: Free-Flow Impeller

ECPJ-L: Balk-type impeller

Customized design for special operating conditions:

Steam-jacketed type (ECPJ-H): Specifically designed for applications involving liquid sulfur and other media that require heat tracing and thermal insulation to prevent solidification.

Inducer (ECPJ-I): When suction conditions are extremely severe and NPSHa is very low, an inducer can be installed to significantly enhance the pump’s suction performance.

A Wide Range of Material Options: We offer alloy materials that comply with API 610 and NACE MR0175/MR0103 standards, as well as specialty corrosion-resistant materials such as titanium alloys, to address the corrosivity of various process fluids. In addition, our pump designs meet the requirements for ATEX Zone 0/Class I hazardous areas.

Robust rotor and bearing system:

Precision-cast impeller: undergoes dynamic balancing calibration to ensure smooth operation and low vibration across a wide flow range.

Anti-rotation impeller nut: securely locks the impeller to the shaft while keeping the threads concealed from the conveyed liquid to prevent corrosion.

Thrust Bearings: Back-to-back arrangement of API 40° angular-contact bearings is employed, thereby ensuring the suitability of standard (non-thrust) motors and meeting the bearing life requirements specified in API 610.

Reliable sealing and connection design:

API 682 Seal Chamber: Allows the installation of cartridge-type single-end, non-pressure dual-end, or pressure dual-end mechanical seals to meet safety and environmental protection requirements.

Metal-to-metal sealing: The pump casing and pump cover are fitted with a metal-to-metal seal, complemented by a fully constrained and controllable compression gasket, to ensure excellent sealing performance and alignment.

📊 Key Performance Parameters
Supplementary Notes on the Performance Parameter Ranges for Flowserve ECPJ (VS4)
The maximum flow rate can reach 1,000 cubic meters per hour (4,400 gallons per minute), which falls within the medium-flow range.
The maximum head can reach 150 meters (500 feet), which falls within the medium-head range achievable with a single-stage design.
The maximum working pressure can reach 20 bar (285 psi), making it suitable for medium-pressure applications.
The operating temperature range is exceptionally broad, spanning from –46°C to 350°C (–51°F to 660°F), making it suitable for a wide variety of industrial media. Steam-jacketed designs, in particular, are capable of maintaining high temperatures.
The maximum installation length can reach 8 meters (26 feet) and can be customized to match the depth of the sump or storage tank.
🏭 Main Application Industries
Thanks to its reliable vertical submersible design and ability to handle special media, Flowserve ECPJ (VS4) pumps are primarily used in the following applications:

Oil and Natural Gas:

Chemical and Hydrocarbon Processing: Collection and discharge of process fluids in sumps and drain pits at refineries and chemical plants.

Tank Farm and Wastewater Treatment: Foot-operated pumps for the tank farm, or for the collection and conveyance of wastewater within the plant area.

Drilling and Production: Fluid Transportation in Auxiliary Production Processes.

Chemistry and Special Processes:

Molten Salt/Sulfur Conveyance (ECPJ-H Type): Specifically designed for special process media that require heat tracing and thermal insulation.

Production of renewable energy fuels.

Power generation:

General plant services: used for auxiliary processes such as sump drainage within the power plant.

Water Resources:

Water Supply and Water Treatment: Used for water intake, industrial water supply, and fluid conveyance within water treatment plants.

Flood control, groundwater development, and irrigation.

General Industry:

Steel, papermaking, shipbuilding, and offshore engineering: used for draining various industrial wastewater ponds.

We hope the information provided above on the Flowserve VS4 pump has been helpful. If you would like to learn about the differences between this model and the Sulzer VS4 pump in terms of selection, or if you wish to compare it with other models such as the VS1 or VS6, please feel free to contact us again at any time.

Casting Capability: Equipped with a variety of refining facilities, including vacuum induction furnaces, VOD furnaces, AOD furnaces, and LF furnaces, the annual casting capacity reaches 40,000 metric tons, with a maximum single-piece weight of 25 metric tons.

Machining Capabilities: We operate more than 300 CNC lathes of various types and a wide range of large and medium-sized CNC machine tools and machining centers, including brands such as OKUMA, OKK, MAZAK, and DAWOO.

Horizontal machining centers, turning centers, vertical machining centers, boring-milling centers, and Mori Seiki horizontal precision machining centers. Annual machining capacity reaches 2 million hours.

Testing Capabilities: Equipped with open-loop and closed-loop test circuits suitable for 380 V, 3,300 V, 6,000 V, and 10,000 V systems, capable of testing motors up to 5,000 kVA.

This open-type test rig has a depth of 12 meters and a volume of 3,600 cubic meters, capable of meeting the testing requirements for most centrifugal pumps and systems.

Annual Production Capacity: An average annual output of 8,000 pumps, encompassing centrifugal pumps, canned motors pumps, reciprocating pumps, screw pumps, and high-speed pumps.

System Integration: Conduct system integration design and consolidation based on product specifications, operating conditions, industry standards, and customer branding requirements.

● Auxiliary equipment: lubrication system, sealing system, flushing system, coupling, etc.

● Drive systems: electric motors, steam turbines, diesel engines, hydro turbines, etc.

● Control System: pressure control, temperature control, vibration monitoring, lubrication monitoring, and leak detection, among others.

● Electrical control systems: DCS, MCC, MMS, VFD, and LCP, among others.

Workshop Equipment: Equipped with a complete production line spanning raw-material laboratory testing, component manufacturing, machining, pump-body assembly, nondestructive testing, dynamic balancing, performance testing, painting, and packaging.

● The workshop covers an area of 20,000 square meters and is equipped with a bridge crane capable of lifting 32 tons with a clear headroom of 12 meters.

● The balance equipment has an accuracy of G1.0.

● Equipped with test circuits capable of withstanding voltages of 380 V, 3,300 V, 6,000 V, and 10,000 V, a motor with a power rating of up to 5,000 kW, and an A-class-accuracy automated data acquisition and processing system.