In the global pulp and paper industry, Andritz® ACP series single-stage centrifugal pumps have become core pumping equipment for key processes such as pulp transportation, pulping cooking, black liquor evaporation, and white water circulation, thanks to their excellent anti-clogging performance, high transmission efficiency, and strong operating condition adaptability. Designed specifically for transporting media containing fibers and solid particles, this pump series can handle pulp with a concentration of 8%. Its operating conditions range from conventional clear water transportation to harsh scenarios involving high temperature, high pressure, strong corrosion, and hazardous media, placing high demands on the adaptability, stability, and reliability of shaft end seals.

Developed to address the structural characteristics of Andritz®ACP pumps and the operational pain points in the pulp and paper industry, the Series 2233 and 2234 are two specialized mechanical seal series for the pulp and paper industry. Strictly adhering to Andritz®ACP pump chamber design standards, both series achieve original factory-level dimensional adaptation and full operating condition coverage. They provide a reliable, long-lasting, and cost-effective sealing solution for Andritz®ACP pumps in pulp and paper enterprises, fundamentally resolving industry pain points such as pump seal leakage, frequent shutdowns, and high maintenance costs.

As benchmark pumping equipment in the pulp and paper industry, Andritz®ACP series pumps adopt a semi-open/full-open impeller design, featuring core advantages of low axial thrust and strong anti-clogging capability. They are widely used in medium transportation across the entire pulp and paper industrial chain. The differentiation of their operating conditions defines four core requirements for mechanical seals: on one hand, they must meet original factory-level dimensional adaptation, where the seal matches the ACP pump chamber and shaft diameter at a 1:1 ratio, supporting direct installation and replacement without mechanical modification to the pump body, thus effectively reducing maintenance downtime; on the other hand, they need to achieve full operating condition compatibility, being suitable for both conventional clear water and low-concentration pulp transportation in the pulp and paper industry, as well as harsh operating conditions involving high temperature, high pressure, particles, strong corrosion, and hazardous media in cooking and evaporation processes, with strong adaptability to operating conditions. At the same time, in response to possible axial movement during ACP pump operation, the seal must have excellent compensation performance to avoid seal failure caused by shaft displacement and ensure long-term continuous operation. Additionally, it must be compatible with various flushing plans specified in API 682 standards, which can be flexibly matched according to different operating conditions to effectively protect the seal face and extend service life.

Both Series 2233 and 2234 are specialized mechanical seal products for the pulp and paper industry. Optimized based on the core design standards of Andritz®ACP pump chambers, they fully cover mainstream shaft diameter specifications of ACP pumps, including 33, 43, 53, 60, 70, 85, and 115mm. From structural design and dimensional matching to operating condition adaptation, they fully align with the operating characteristics of ACP pumps, enabling direct installation and replacement without modification. The two series correspond to different operating scenarios in the pulp and paper industry, forming a full-scenario sealing protection system.

Series 2233 mechanical seals feature a single-end seal structure, designed specifically for general operating scenarios of ACP pumps in the pulp and paper industry, serving as an adaptive solution for conventional transportation processes in the pulp and paper industry.

The product adopts a static compensation seal face combined with a balanced design, paired with a multi-spring compensation structure, boasting significant core advantages: the multi-spring layout ensures more uniform compensation force on the seal face, effectively improving the dynamic fit of the face, reducing uneven wear caused by fiber particles in the medium, and greatly extending the service life of the seal; the balanced design can effectively offset the additional specific pressure of the medium on the seal face, reduce frictional power consumption of the face, and adapt to stable operation under medium and low pressure conventional operating conditions; the static compensation design avoids the interference of spring centrifugal force and medium turbulence on compensation performance during high-speed operation compared with traditional rotating compensation structures, resulting in more sensitive compensation response and stronger seal stability.

Series 2234 mechanical seals feature a double-end seal structure, tailored specifically for harsh medium operating conditions of ACP pumps in the pulp and paper industry, serving as a core safety guarantee for high-risk processes such as cooking, evaporation, and hazardous medium transportation.

The product adopts a static compensation seal face, balanced design, and double-end single-group multi-spring structure, achieving specialized performance breakthroughs for harsh operating conditions in the pulp and paper industry: the unique structural design completely solves the impact of pump shaft axial movement on spring load. Even if the ACP pump has axial displacement during operation, it can maintain a constant spring compensation force, fundamentally avoiding seal failure caused by shaft movement; the double-end structure forms a dual sealing protection system, creating a safety barrier through isolation fluid to effectively prevent pulp black liquor, corrosive chemicals, and hazardous media from leaking outward, fully meeting the strict safety production and environmental compliance requirements of the pulp and paper industry; the combination of balanced design and static compensation design ensures stable fit of the seal face even in high-temperature, highly corrosive media containing high-concentration fiber particles, resisting medium erosion and abrasion, and ensuring long-term operation under harsh operating conditions.

In addition to specialized optimization for different operating conditions, as specialized pulp and paper industry seals for Andritz®ACP pumps, Series 2233 and 2234 have four core common advantages, fully matching the production needs of the pulp and paper industry. Both series are developed in strict accordance with Andritz®ACP pump chamber design standards, with installation dimensions fully matching the original factory pump. They can directly replace the original factory seal without any mechanical modification to the pump body or chamber, significantly reducing equipment maintenance downtime and modification costs, achieving original factory-level adaptation and direct installation without modification. At the same time, both are specialized seal series for the pulp and paper industry, deeply matching the operating characteristics of the entire pulp and paper process (including pulping, cooking, evaporation, and pulp transportation) from the design source. They have been specially optimized for pain points such as fibers, particles, high temperature, and corrosion in pulp media, serving as a specialized sealing solution for ACP pumps in the pulp and paper industry. In terms of core structure, the two series share the same optimized design, both adopting a static compensation seal face and balanced structure. Compared with traditional rotating compensation structures, they effectively avoid the interference of spring centrifugal force and medium turbulence on compensation performance during high-speed operation, resulting in more sensitive and stable compensation. The balanced structure also effectively reduces the specific pressure of the seal face, reduces face wear, significantly extends the service life of the seal, and lowers the total life cycle maintenance cost of the equipment. Additionally, both series fully cover mainstream shaft diameter specifications from 33mm to 115mm, compatible with all models of Andritz®ACP pump series. They are also compatible with mainstream industry API flushing plans, which can be flexibly matched with suitable sealing solutions according to the different processes and operating conditions of pulp and paper enterprises.

The two specialized seal series, 2233 and 2234, provide a reliable, long-lasting, and cost-effective sealing solution for Andritz®ACP pumps in pulp and paper enterprises worldwide, with original factory-level adaptation accuracy, industry-specific structural design, and full operating condition coverage. Whether for long-term stable operation under conventional operating conditions or safe protection under harsh operating conditions, Series 2233/2234 can be perfectly adapted, helping pulp and paper enterprises improve equipment operation efficiency, reduce the risk of unplanned shutdowns, and achieve the dual goals of safe production and cost reduction and efficiency improvement.