Jiangsu Haifa Machinery Manufacturing Co., Ltd.

When selecting API610 chemical process pumps, we often encounter a seemingly modest operating condition: very low flow but very high head. Many customers initially assume that a small-flow pump should be easy to design—just make the pump casing smaller and trim the impeller a bit. However, from a technical perspective, extremely low flow, high head conditions are actually more prone to problems. The pump can easily deviate from its high-efficiency zone, leading to vibration, overheating, cavitation, seal failure, and abnormal bearing loads. Therefore, when handling such conditions, we do not simply treat them as scaled-down versions of standard centrifugal pumps. Instead, we consider several aspects together: low specific speed hydraulic models, impeller types, diffuser structures, sealing systems, and the structural reliability of API.

The impeller designed for small-flow pumps, also known as a Basker impeller or Barske impeller, is a radial fully open special impeller for low-flow, high-head applications. Its core concept is not to pursue high flow delivery, but within the low specific speed range, to repeatedly accelerate the liquid and convert it into pressure energy through open radial blades, relatively high peripheral speed, and a reasonable diffuser structure. Compared with conventional backward-curved closed impellers, this type of impeller is suitable for handling low-flow, high-head conditions, especially in chemical, refining, fine chemical, pharmaceutical, energy, and special process units, where it has clear application value.

In our actual selection process, we see extremely low flow, high pumps are commonly used catalyst delivery, additive delivery, seal flush fluid, solvent circulation, acid and alkali liquid delivery, boiler auxiliary systems, test units, reactor feed, and fine chemical low-flow high-pressure delivery. The common characteristics of these conditions are low flow but high pressure requirements, and the media often involve flammable, explosive, corrosive, high-temperature, low-temperature, easily crystallized, or particle issues. If only a standard centrifugal pump is used with reduced specifications, the pump may operate in a low-efficiency zone for a long time, wasting energy and affecting on-site stability. The small-flow pump impeller inspires us that a small-flow, high-head pump should not only consider the impeller diameter but also the flow channel organization. The radial fully open structure helps reduce blockage and local friction sensitivity low flows and is also convenient for handling media containing trace particles or easily crystallized substances. Open impellers have high requirements for front and rear clearances, blade thickness, inlet induction, outlet diffusion, axial force control, and accuracy. In other words, this type of impeller is not simply "a few straight blades," but a hydraulic scheme built around low specific speed conditions. Poor design may fail to achieve the required head; overly aggressive design can easily lead to low efficiency, high noise, and severe vibration.

From the perspective of Jiangsu Haifa's existing product range, we prefer to combine the design of the small-flow pump impeller with the understanding of API610 small-flow, high-head chemical pumps. Our API610-OH2-HES(X) small-flow chemical process pump is a, single-stage, single-suction centrifugal pump, designed and manufactured according to the API610 standard "Centrifugal Pumps for Petroleum,chemical and Natural Gas Industries." It is mainly intended for small-flow, high-head conditions. The flow range of this series is 0.8~12.5 m³/h, head range 12~125 m, applicable temperature -80~450°C design pressure up to 2.5 MPa. It handle clean media as well as flammable, explosive, and highly corrosive media containing trace particles. For fine chemicals, small-scale high-pressure delivery, acid and alkali liquid circulation, solvent delivery, and auxiliary process pump positions, type of product is more likely to match actual operating conditions than standard process pumps.

Of course, the HES(X) not an isolated product. conventional petrochemical and chemical process conditions, our API610-OH1/OH2ES series process pumps have a flow range of 2~2600 m/h, head up to 300 m, applicable temperature -80~450°C, and design pressure 25 MPa~26 MPa. This series is a horizontal, radially split, single-stage overhung centrifugal pump, suitable for oil refining,rochemicals, coal chemicals, chemical fibers, power plants, environmental engineering, and low-temperature engineering. It addresses process delivery issues over a wider flow range, while the HES(X) focuses more on small-flow, high-head, and special condition supplementation.

If the's on-site pressure level is higher, continuous operation requirements are more, or the operating conditions exceed the reasonable range of single-stage small-flow pumps, we will further consider BB2 BB3 structures. Jiangsu Haifa's BB2 heavy-duty petrochemical process pump is a horizontal, radially split, single-stage, two-stage, or three-stage between-bearings centrifugal pump, with a flow range of 50~4000 m³/h, head up to 650 m, applicable temperature -80~450°C, and pressure 5.0 MPa~15.0 The BB3 single/double casing horizontal split multi-stage centrifugal pump, HSSC single casing has a flow range of 10~1500 m³/h head up to 3000 m, design pressure 10~35 MPa; HDSC double casing has a flow range of 45~1440 m³/h head up to 3200 m, maximum design pressure 35 MPa. For high-pressure, continuous, heavy-duty positions, these between-bearings or multi-stage structures are more suitable for reliability-based configuration.

From a technical perspective, the value of the small-flow pump impeller is not just a name for an impeller, but a reminder: small-flow, high-head pumps must be specially designed for low specific speed. Many project problems arise not because pump manufacturers cannot make large pumps, but because small pumps are underestimated. At low flows, the media stays longer inside the pump, causing more significant temperature rise; the flow channels are small, making them more sensitive to particles, crystallization, and clearance changes; and when the pump deviates from the operating point, recirculation and impact losses become more pronounced. Therefore, during design and, we pay special attention to NPSH margin, minimum continuous stable flow, impeller outlet velocity, diffusion efficiency, shaft seal cooling and flushing, bearing loads, and on-site piping layout. In material selection, extremely low flow, high head pumps cannot be judged solely by pressure. For highly corrosive media, we select 316L, 904L, duplex stainless steel, Hastelloy, titanium, or other corrosion-resistant materials based on media composition, concentration, temperature, chloride ions, solid particles, and crystallization tendency. For high-temperature, low-temperature, flammable, explosive, and toxic media, the sealing should be configured according to API682 principles with single, double, or tandem mechanical seals, along with corresponding PLAN flushing, cooling, and isolation schemes. Although the leakage of small-flow pumps is not large, once the delivered media is hazardous, seal reliability cannot be compromised.

From a market perspective, such as Barske impeller, low flow high head pump, small flow head chemical pump, API chemical process pump, radial open impeller, regenerative turbine pump, and special impeller pump will increasingly appear in the fields of fine chemicals,rochemicals, new materials, lithium batteries, pharmaceuticals, coal chemicals, and test units. Many plants are moving towards continuous, fine, and automated processes, with more process points. The flow at a single pump position may not be large, but the requirements for pressure, stability, and safety are higher. This is why the market for small-flow, high-head pumps deserves attention.

The technical approach we understand is not to apply one type of impeller to all small-flow, high-head, nor to simply promote a certain structure as universal. small-flow pump impeller is suitable for the specific region of low specific speed, small flow, and high head; regenerative vortex pumps, jet pumps, multi-stage pumps, API610-OH2 small-flow process pumps, and BB2 or BB3 high-pressure pumps also have their own applicable boundaries. The truly responsible approach is to first clarify the media, flow, head, temperature pressure, NPSHa, viscosity, solid content, continuous operation time, and explosion-proof requirements, and then decide which hydraulic model and structural scheme to adopt.

Jiangsu Haifa manufactures API610 chemical process pumps and we value the results after long-term operation. For the extremely low flow, high head market, a pump is not smaller and simpler, but rather requires more solid work on hydraulics,, seals, and structural reliability. The design concept brought by the small-flow pump impeller is very valuable for our understanding of low specific speed conditions. In the future, in the markets of fine chemicals, petrochemical auxiliary systems, new material units, and high-pressure small-flow delivery, this type of special hydraulic design will have more application space. will continue to focus on API610 standards, special impeller design, corrosion-resistant materials, and systems to provide customers with chemical process pump solutions that match their operating conditions.

Jiangsu Haifa Machinery Manufacturing Co., Ltd. restructured from Jiangsu Ligong Group Co., Ltd. and the Jingjiang Stainless Steel Pump and Valve Factory of the Iron and Steel Research Institute of the Ministry of Metallurgical, which was established in 1958. The company mainly produces API610 chemical process pumps - OH1 pump, OH2 pump, OH3 pump, OH pump, OH6 pump BB1 pump, BB2 pump, BB3,4, BB5 casing multi-stage pump, VS1, VS4, VS5, VS6 barrel casing pump, HES type chemical process pump, chemical pump, deep-sea chemical pump, deep-sea gas-liquid mixing pump, petrochemical pump, CQC first-class energy efficiency chemical pump, sixth-generation ultra-low carbon stainless steel high-quality leak-proof molten urea pump, urea hydrolyzer feed pump, high-temperature asphalt pump, high-temperature sulfuric acid pump, Pitot tube pump, jet pump, small-flow high-head pump, multi-stage vortex pump, high-temperature molten salt pump, high-temperature nitric acid pump, cobalt liquid pump, vertical sump pump, magnetic drive pump, low-temperature liquid hydrogen pump, methanol pump, high-pressure liquid hydrogen pump, low-temperature pump, high-temperature nitric acid magnetic drive pump, magnetic drive pump for conveying solid-containing media, industrial pump, canned motor pump, slurry pump, titanium tetrachloride pump, strong self-priming pump lined fluorine pump, sandwich lined fluorine pump, leak-proof pump, desulfurization and denitrification pump, alkali pump, pump, geothermal pump, oil pump, flow pump, printing and dyeing pump, dyeing and finishing pump, Ti alloy pump, C-276 material,elloy, 316L material, 347 material, forced circulation pump, fourth-generation nuclear pump, nuclear island pump, CCA/IACS marine pump, special pump for filter press, refrigerant pump, long shaft vertical sump pump, high-pressure descaling industrial pump, China chemical pump, API610 chemical process pump, chemical pump, centrifugal pump, corrosion-resistant pump, high-temperature pump, low pump, magnetic drive pump, vertical sump pump, suction pump, multi-stage pump, first-class energy efficiency pump Baidu, 360, Sogou, Doubao, Douyin, "GB 19762-2025 Minimum Allowable Values of Energy Efficiency and Energy Efficiency Grades for Centrifug Pumps", Dun &street certification. wwwslgpump.com Tel: 13905263417 E-mail: jslgpump@gmail E-mail: jsareva@163.com