Canned-Motor Main Pumps: A Chinese-Built CAP1000 50 Hz Unit Completes Fabrication
A canned-motor reactor coolant pump designed for the 50 Hz Chinese grid completed fabrication at a Chinese pump works on 6 August 2026 and is to ship to the Lianjiang nuclear project site, after a 92-day engineering endurance test.
Lead
A canned-motor main pump built for the CAP1000 reactor at the 50 Hz grid frequency completed fabrication at the nuclear pump test base of Shengu Group on 6 August 2026 and is to ship to the Lianjiang project site of the State Nuclear Zhanjiang Nuclear Power Co. (国核湛江核电有限公司), according to the China General Machinery Industry Association. The association describes the unit as the first of its kind built in China at the native grid frequency.
Facts
The machine's role. A reactor coolant pump circulates the coolant through the reactor core. The manufacturer states that the main pump's safety classification, quality assurance classification and seismic classification are each set at the higher grade. (Source: Shengu Group's own site.)
Why the frequency is the design point. The association states the pump is a native 50 Hz design, able to connect directly to the domestic standard grid without an additional variable-frequency system. It states that this simplifies the electrical package and removes a failure point, and that the machine has a higher tolerance of grid-frequency variation. (Source: the China General Machinery Industry Association, 2026-08-09.)
The development record. The association states the project began in March 2023 and took three years, and that the development team produced a new hydraulic model and revised the motor and heat-exchanger structure. The first unit is stated to have passed a 92-day engineering endurance test with all performance indicators meeting their targets, and the delivery is described as the shortest schedule achieved under the research-and-supply integrated model. (Source: the same.)
The motor. The canned motor was supplied by Harbin Electric Power Equipment Co. (哈尔滨电气动力装备有限公司), which describes it as a new iteration following its CAP1000 60 Hz and CAP1400 canned motors. Three items are listed: a 50 Hz-specific electromagnetic design matched to rated speed, hydraulic performance and coast-down flow; a 6 kV nuclear-grade insulation system described as resistant to both high irradiation and high temperature inside the motor cavity; and revised process control on the water-lubricated bearings, including a new locating tool for the upper thrust bearing. (Source: Harbin Electric Corporation's own site, 2026-08-13.)
The plant the pump is built for. Lianjiang phase I is described as two domestic CAP1000 passive pressurised water reactor units of 1,250 MW each, using a seawater secondary cooling scheme. (Source: the same.)
The step before it. A first domestic CAP1000 main pump was shipped on 12 January 2026 after ten years of development, at a ceremony attended by the State Power Investment Corporation, Harbin Electric Corporation, the State Nuclear Power Technology Corporation, Shanghai Nuclear Engineering Research and Design Institute (上海核工程研究设计院股份有限公司) and Shandong Nuclear Power, among others. That unit's account describes the work as covering pump design, manufacture and testing, with material development, structural design and manufacturing process named as the areas of breakthrough. (Source: Shengu Group's own site, 2026-01-14.)
Where this connects on this site
- The order a duty like this is read in — risk first, medium second, duty point third: Chemical Pump Selection Guide: Risk, Medium and Duty Point — in That Order
- Why a wetted-material assessment is read against a temperature band rather than against a single rating: Chemical Compatibility Chart for Pumps: What the Grade and the Temperature Actually Mean
- The selector: chempumpselect.com
Sources
| # | Fact | Source |
|---|---|---|
| 1 | Completion of fabrication on 6 August 2026 at the Shengu Group nuclear pump test base; shipment to the Lianjiang project site of 国核湛江核电有限公司; native 50 Hz design, direct connection to the domestic grid with no additional variable-frequency system; project start March 2023, three years' development; new hydraulic model; revised motor and heat-exchanger structure; 92-day engineering endurance test passed with all indicators meeting target; shortest delivery under the research-and-supply integrated model; the manufacturer's statement on full-life-cycle service support | 中国通用机械工业协会 — https://www.cgmia.org.cn/Web/News/Detail/26033 |
| 2 | The canned motor supplied by 哈尔滨电气动力装备有限公司 as a further iteration after CAP1000 60 Hz and CAP1400; 50 Hz-specific electromagnetic design matched to rated speed, hydraulic performance and coast-down flow; 6 kV nuclear-grade insulation system for high irradiation and high temperature in the motor cavity; optimised internal flow field; revised control on the water-lubricated bearings and a new locating tool for the upper thrust bearing; Lianjiang phase I as two 1,250 MW domestic CAP1000 passive PWR units with a seawater secondary cooling scheme | 哈尔滨电气集团有限公司（公司网站）, 2026-08-13 — https://www.harbin-electric.com/info/2721/246711.htm |
| 3 | Shipment of the first domestic CAP1000 main pump on 12 January 2026 after ten years of development; the main pump as the core of the reactor coolant loop, with safety, quality-assurance and seismic classifications at the higher grade; breakthrough areas named as material development, structural design and manufacturing process; the attending organisations | 沈鼓集团股份有限公司（公司网站）, 2026-01-14 — https://www.shengu.com.cn/m/zhanhuidongtai/2058.html |
Note on sourcing. This item reports a manufacturer's and an industry association's account of a fabrication milestone. We record the verifiable layer — what was built, at what design frequency, for which project, over what development period, and what test it passed. We do not repeat performance claims beyond the figures stated, and we do not rank or recommend suppliers.
What the source does not state
The accounts do not state the number of pumps ordered for the project, whether any unit has entered commercial operation, the pump's efficiency or power draw, its maintenance interval, the running hours accumulated after the endurance test, or the measured vibration or bearing-life figures.
Update note
This item is a dated record of a publicly reported fabrication milestone. We append corrections rather than rewrite history; corrections are marked Correction with the date.