horizontal double‑casing multistage pump

The ocean is a strategic priority for high-quality development strategies. First half of 2026 China's marine GDP amounted to RMB 5.5 trillion. Accounting for 7.9% of GDP The marine economy is emerging as a "blue engine" driving high-quality development.   Recently, Leo Pump Industry was awarded a contract with CNOOC. 2026–2027 Fixed-Platform Multi-Stage Centrifugal Injection Pump (BB5 Type) Tier-1 Centralized Procurement Framework Agreement Project Establish itself as a leader in the high-end marine oil and gas equipment sector. Another milestone project     Project Context  China National Offshore Oil Corporation (CNOOC) is a mega-central state-owned enterprise directly under the administration of the State-owned Assets Supervision and Administration Commission of the State Council, and it is China's largest offshore oil and gas production operator; it ranks 65th on the 2025 Fortune Global 500 list. In anticipation of the potential demand for injection pumps in engineering projects over the coming year, CNOOC has launched the bidding process for the "2026–2027 Fixed Platform Multi-Stage Centrifugal Injection Pump Primary Central Procurement Project."     The centralized procurement scope covers multiple sets of multi-stage centrifugal injection pumps (BB5 pump model); the supplied equipment will be extensively deployed on fixed platforms, FPSOs, and other floating installations in the Bohai Sea, East China Sea, South China Sea, and other maritime areas under China National Offshore Oil Corporation (CNOOC).   As a primary centralized procurement framework agreement applicable to the entire China National Offshore Oil Corporation (CNOOC) Group, the equipment covered by this agreement shall, in principle, not be subject to any form of circumvention; all equipment requirements during the term of this agreement must be met in accordance with the parameters specified in the agreement.   This represents not only a comprehensive assessment of the winning bidder's overall capabilities—including technical expertise, delivery capacity, service assurance, and brand credibility—but also signifies that being shortlisted grants the bidder priority supply status for all water injection pump demand across CNOOC's entire maritime area over the next two years—a benefit far exceeding the value of the individual order itself.     As early as 2025, Leo Pump Industry successfully secured the annual procurement contract for offshore injection pump units for the South China Sea region under China National Offshore Oil Corporation (CNOOC), marking its first breakthrough in supplying high-end critical upstream process equipment for offshore platforms. For this project, Leo once again stood out and won the bid by leveraging its core technological advantages in ultra-high-pressure operating conditions, marine corrosion resistance and anti-corrosion solutions, compact space vibration control, as well as its established service reputation accumulated within the petrochemical industry.     Project Challenges  The offshore platform water injection pump is often referred to as the "offshore heart"; its operating conditions are far more demanding than those encountered in onshore industrial applications. Therefore, this project imposes the following requirements on the core technologies of the equipment supplier's products:   ① Stable operation under ultra-high head and ultra-high pressure conditions The pump inlet pressure reaches 12 MPa, the flow rate is 290 m³/h, and the head is 1300 m; these operating conditions pose significant challenges to the durability and structural integrity of both the mechanical seal and the pump body. Ensuring the long service life of the mechanical seal under such ultra-high inlet pressure represents the primary challenge.       ② Durability challenges in marine corrosion environments The high-salt-spray and high-humidity conditions in marine environments can readily induce electrochemical corrosion in contacting metals, thereby accelerating the corrosion rate of pump components and imposing extremely stringent requirements on the corrosion resistance of these materials. Moreover, certain marine areas are characterized by "wet hydrogen sulfide" environments – where the coexistence of H₂S and water poses risks of sulfide stress corrosion cracking and hydrogen-induced cracking, representing the most significant threat to equipment safety.     ③ Effective spatial and vibrational control The installation space on offshore platforms is extremely limited, imposing strict constraints on the external dimensions of wind turbines. Additionally, CNOOC has stringent requirements regarding turbine vibration performance; traditional grouted foundation bases are not suitable for offshore drilling platforms. Addressing the issue of resonance in non-grouted foundations poses a significant challenge for designers.   LEO Solution  In response to the aforementioned challenges, the Leo T-Series (Model BB5) horizontal twin-casing multi-stage pump has delivered outstanding performance through systematic technological innovation. This model has withstood prolonged operational testing in major projects, such as the PetroChina Guangxi Petrochemical Integrated Refining and Chemical Transformation and Upgrading Project and the 1.7 million tons/year residue hydroprocessing unit at Sinopec Changling Branch, accumulating extensive experience in applications under complex operating conditions. Building upon this proven track record, Leo's technical team has undertaken a systematic, customized design and validation process specifically tailored for marine environments:       ① High-voltage response – Dual Protection For high-pressure operating conditions at the inlet, the pump incorporates an internal pressure-reducing structure that effectively mitigates the impact of high-pressure media on the mechanical seal; simultaneously, a mechanical seal designed to withstand high pressures is employed, providing dual protection. The pump body structure has been subjected to finite element analysis (FEA) for enhanced design, ensuring reliable pressure-bearing capability.       ② Structural innovation: combining rigidity with flexibility The BB5 design employs a dual-shell inner core with a horizontal partitioning structure, where the inner core features a horizontal partitioned volute configuration with symmetrically arranged impellers. Compared to traditional segmented inner core designs, this approach not only significantly enhances overall pressure-bearing capacity and rigidity while effectively suppressing deformation and vibration under high-pressure conditions, but also substantially reduces both axial and radial forces through optimized hydraulic balancing.   The inner core's casing shoulder is machined according to the rotor's deflection profile, ensuring a uniform clearance between the rotor and the friction pair; as no complex balancing mechanism is incorporated internally, the operational stability of the equipment when handling particulate media on conveyor belts is significantly enhanced.       ③ Anti-corrosion and corrosion resistance – Comprehensive protection For high-humidity and high-salt-spray environments, certain components of the LEO BB5 model are manufactured using specialized materials; the surfaces of the fastening components are coated with PTFE, while carbon steel components are treated with a special coating. This prevents electrochemical reactions that could accelerate metal corrosion in salt-spray environments; insulating gaskets with excellent electrical insulation properties and strong mechanical performance are installed between different metal parts. To mitigate hydrogen sulfide-induced corrosion, material properties are enhanced to prevent stress corrosion cracking at the source. The friction pairs are subjected to a specialized hardening process, ensuring both wear resistance and resistance to seawater corrosion.       ④ Compact design – no vibration concerns The Leo technical team has implemented a customized, compact design tailored to the specific spatial dimensions of the site; to prevent resonance issues in non-grouted foundations, a special-profile foundation design has been adopted, with the structure reinforced through rigorous strength verification.       ⑤ High efficiency, energy savings, and sustainable operation By employing an advanced hydraulic model with pump efficiency compliant with the Class 1 energy efficiency standard specified in GB/T 19762-2025, and integrating it with a high-efficiency variable-frequency drive system, the pumps operate within their high-efficiency range under the majority of operating conditions. Compared to the existing equipment, this solution is expected to deliver significant energy savings and reduced energy consumption, thereby lowering the operational costs of the oilfield.   ⑥ Easy operation and maintenance – saves time and effort The pump core assembly can be removed and replaced as a single unit; the rotor can be assembled or disassembled as a whole; both the inner housing and the friction pair feature a split-assembly design, making maintenance and repair straightforward and requiring minimal technical expertise from maintenance personnel, thereby significantly reducing the complexity of maintenance tasks. The housing ring and bushing can be replaced without disassembling the impeller, which greatly shortens the on-site maintenance cycle.   ⑦ Comprehensive solution package – one-stop delivery Leo offers comprehensive turnkey solutions, including control systems, giving clients peace of mind and confidence.   Flow Towards The Future  In 2025, Leo Pump Industry established a partnership with China National Offshore Oil Corporation (CNOOC), winning the bid for the "Annual Procurement Agreement Project for Submersible Injection Pumps in the South China Sea Region" initiated by CNOOC's equipment subsidiary. Leveraging this opportunity, Leo began to establish itself in the high-end equipment segment for upstream offshore platform processes. In 2026, Leo once again secured a first-tier centralized procurement framework agreement for multi-stage centrifugal injection pumps (BB5 pump model) for CNOOC's fixed platforms.   This not only represents a dual recognition of Leo's robust product capabilities and comprehensive service ecosystem, but also signifies that Leo has achieved a transformative leap—from a "single-point breakthrough" to "comprehensive expansion" —within the high-end marine oil and gas equipment sector.     By leveraging maritime capabilities and achieving technological self-reliance, marine oil and gas resources serve as a vital pillar in safeguarding national energy security. As General Secretary Xi Jinping emphasized, it is essential to enhance China's independent innovation capacity in marine science and technology and promote the high-quality development of the marine economy. During the 15th Five-Year Plan period, China will focus on breaking through the "bottleneck" challenges surrounding certain high-end instruments and critical components.   Leo will also transform its high-end industrial pump products, developed through independent innovation, into a "sharp sword," continuously providing core equipment support for the development of China's offshore oil and gas resources, thereby serving the national energy security strategy through concrete actions. Leo is committed to contributing its strength to China's endeavor to build itself into a maritime power and to bolster its marine economy!