Jiangsu Haifa Machinery Manufacturing Co., Ltd.

Manufacturer: Jiangsu Haifa Machinery Manufacturing Co., Ltd (restructured in 1958, deeply engaged in R&D and manufacturing of API 610 petrochemical pumps, serving refining, polypropylene, and coal chemical complete plants) In the polypropylene process, unreacted propylene must be continuously circulated back to the reactor. Propylene has low viscosity, high saturated vapor pressure, and is highly prone to vaporization. Meanwhile, the process requires low flow and high head, making it difficult for conventional centrifugal pumps and multistage pumps to simultaneously meet the anti-cavitation and high-pressure discharge requirements. Jiangsu Haifa has the API 610 OH6 high-speed overhung propylene circulation pump, which utilizes a speed-increasing gearbox plus a single-stage high-speed impeller to achieve a head of over 500 m in a single stage, used for propylene-propane circulation in polypropylene plants.

I. Actual Operating Conditions (benchmarked against the P-1301A/B propylene pump specifications in polypropylene plants)

| Parameter | Value |
|
| Pump model | API 6106 high-speed centrifugal pump |
| Medium | Propylene, propane |
| Normal flow rate | 28.3³/h |
| Maximum flow rate | .4 m³/h| Head | 560 m |
| Suction pressure | 1.92 MPa(g) |
| Discharge pressure | 4.50 MPa(g) |
| Operating temperature | 39–55°C |
| Medium density | 470 kg/m³ |
| Medium viscosity | 0.055 cP |
| NPSHa | 4.6 m |

II. Core Structural Features of the OH6 High-Speed Pump

Single-stage high-speed impeller + speed increasing
Unlike BB5 multistage pumps, the OH6 is equipped with a speed-increasing gearbox that raises impeller speed, allowing a single-stage impeller to deliver high head. This simplifies the overall structure, reduces equipment footprint, and is ideally suited for low-flow, high-head light hydrocarbon applications.

Drive train: motor → speed-increasing gearbox → high-speed shaft → single-stage impeller →user → pump discharge.

Diffuser pressure recovery configuration
Equipped with a diffuser to reduce high-speed fluid impact losses, improve pressure conversion efficiency, impeller discharge energy losses, and overall hydraulic efficiency.

III. Seal System for Propylene Service (per API 682)

Propylene is a volatile, flammable, and explosive light hydrocarbon medium, and seal reliability directly determines plant safety. This solution adopts a single mechanical seal combined with Plan 32 + Plan 53B flush schemes.

Plan 32: External clean propylene is introduced as the flush medium to lubricate and cool the seal faces, suppress medium vaporization, and seal service life. Flush medium pressure: 4.26/342 MPa(g), temperature: 37°C.

Plan 53B: White oil is used as the barrier fluid to prevent process medium from entering the bearing housing, improving the safety rating of continuous unit operation.

IV. Flow-Wetted Parts Materials and Low-Temperature Design

Propylene throttling and pressure reduction produce low temperatures, so the equipment must meet low-temperature impact toughness requirements. Minimum design metal temperature: −47°C.

| Component | Material |
|---|---|
| Pump casing | ASTM A351 CF8 |
| Impeller | ASTM A351 CF8 |

V. Core of Jiangsu Haifa OH6 Propylene Pump

High-speed rotor system control: Rotor dynamics analysis is performed, high-speed dynamic balancing is strictly executed, and shaft vibration and deflection are controlled to ensure long-term stable operation of the gear and high-speed shaft.

API 682 seal configuration: integrated Plan 32/53B scheme is specifically matched to propylene's volatile characteristics.

Explosion-proof design: The complete unit meets Zone 2 explosion-proof requirements, with explosion-proof rating Exd IIB T2, compliant with petrochemical site explosion-proof regulations.

VI. Application Scenarios

Polypropylene plants: propylene circulation pumps, prop feed pumps
Petroleum refining: LPG circulation, light hydrocarbon transfer
Coal chemical industry: LPG systems, light hydrocarbon circulation service
Low-temperature engineering: transfer of various volatile light hydrocarbon media

VII. Conclusion

With the continued expansion of domestic refining-integration and polypropylene projects, the demand for localized high-speed light hydrocarbon pumps is steadily increasing. The OH6 high-speed pump, with its single-stage high head, compact structure, and safe and reliable seal system, has become key equipment for propylene circulation inpropylene plants. Leveraging its API 610 manufacturing experience, Jiangsuifa can provide complete localized high-speed pump solutions for propylene, propane, LPG, and other light hydrocarbon media for petrochemical projects both domestically and internationally.

FAQ

Q1: Why choose the OH6 high-speed pump instead of a BB5 multistage pump for propylene circulation?
A: Propylene circulation is typical low-flow, high-head application. BB5 multistage pumps to deviate from BEP in the low-flow range, resulting in low efficiency and high vibration. The OH6 achieves single-stage high head through speed increasing, making the overall structure simpler better suited to volatile light hydrocarbon media.

Q2: Is the Plan 32 + 53B combined seal scheme standard for propylene service?
A: For flammable, explosive, and light hydrocarbon media, Plan 32 external flushing eliminates seal face vaporization risk, when combined with the B barrier system, significantly reduces the risk of medium leakage It is a mature and reliable configuration for polypropylene propylene circulation pumps.

Reference Standards

API 610 Centrifugal Pumps for Petroleum, Petrochemical and Natural Gas Industries
API 682 Shaft Sealing Systems for Centrifugal and Rotary Pumps
GB/T 34807 Rotor Dynamics Evaluation of Centrifugal Pumps

TDK:

Chinese Title: API610‑OH6 高速丙烯循环泵｜聚丙烯装置轻烃输送解决方案
Meta Description: 江苏海珐 API610 OH6 高速丙烯循环泵，适配聚丙烯丙烯丙烷循环，小流量高扬程，配套 API682 Plan32+53B 密封，满足轻烃易汽化工况国产化需求。
English Title: API 610 OH6 High‑Speed Propylene Circulation Pump for Polypropylene Plant
English Meta Description: Jiangsu Haifa API 610 OH6 high‑speed centrifugal pump for propylene‑propane circulation in polypropylene unit, small flow high head with API 682 seal Plan32+53.

Image Tags

1. Full unit photo

Chinese ALT: 江苏海珐 API610 OH6 高速丙烯泵，聚丙烯高速离心泵 English ALT: Jiangsu Haifa API610 OH6 high‑speed propylene circulation pump for polypropylene plant

1. Structural schematic

Chinese ALT: OH6 高速泵齿轮增速结构示意图，单级叶轮扩压器结构 English ALT: OH6 high‑speed pump gear‑box drive structure diagram with diffuser

1. Rotor assembly photo

Chinese ALT: OH6 高速泵高速转子组件，高速动平衡校验部件 English ALT: High‑speed rotor assembly of API610 OH6 after dynamic balance test

1. Seal system schematicChinese ALT: 丙烯泵 Plan32+Plan53B 密封冲洗方案原理图

English ALT: Seal flush plan 32 & 53B schematic for propylene pump