FIXING SYSTEM: hydraulic efficiency that lasts over time

In a constantly evolving industrial landscape, innovation is not only a necessity but a key driver of progress.

In the field of water handling and treatment—an increasingly precious and limited resource—innovation means combining performance with sustainability. Improving performance translates into higher system efficiency, reduced operating costs, and lower energy consumption, ultimately supporting a responsible management of the water cycle.

Caprari stands at the forefront of this evolution thanks to its continuous commitment to developing technologies designed to deliver efficiency, reliability, and durability across the pumping sector.

A highly specialized technical department enables the company to design tailored solutions and develop systems that simplify maintenance, improve performance, and ensure long-term operational continuity.

Submersible KCA pumps for heavy-duty applications: efficiency, reliability and practicality

Among the most recent innovations is FIXING SYSTEM, an internationally patented system that allows fast and precise impeller wear disk adjustment, without having to disassemble the pump.

The system is integrated into the KCA submersible pumps of the K+ ENERGY series, which stand out for:

• optimised hydraulic profiles, with efficiency above 80%;
• IE3 high-efficiency motors;
• the patented DRY WET cooling system, which allows use both in the tank and in the dry chamber;
• the K+ NON STOP anti-clogging system, which prevents blockages and ensures continuous operation;
• a twin-blade open impeller, ideal for liquids containing suspended solids;
• a stainless steel version for aggressive liquids.

These pumps are used in a wide range of applications: wastewater treatment plants, lifting stations, first-rain tanks, and industrial plants where conveying aggressive liquids or solids-laden fluids requires high reliability and operational continuity. In these demanding contexts, simplified disassembly becomes crucial due to the need for periodic inspection and maintenance to ensure the constant efficiency f the systems.

Why Fixing System was developed: maintaining pump hydraulic efficiency 

 During normal operation, several factors can alter the gap between the impeller and the suction wear disk: vibrations, the presence of suspended solids, and component wear.

This detail is crucial: even a minimal variation in this gap leads to head loss, increased energy consumption, and a general drop in performance. Restoring the correct spacing ensures that the fluid enters the impeller at the optimal design angle—a key condition for maintaining high efficiency and reducing head losses.

This hydraulic efficiency must also be restored after any maintenance requiring pump disassembly, such as replacing mechanical seals or bearings. Here again, an easy and precise procedure becomes a major advantage.

A simple and precise system 

With traditional systems, adjusting the impeller-to-wear-disk distance is a long and complex operation: it requires complete pump disassembly, measuring instruments, precise calculations, and extended downtime.

Caprari’s FIXING SYSTEM radically simplifies and revolutionises the process.
The key advantage is the ability to adjust the gap between the impeller and the suction disk from the outside, by acting on three screws with related nuts and locknuts placed near the pump suction area.

This allows operators to restore the optimal distance in under a minute, keeping hydraulic performance at design level and ensuring maximum operational efficiency throughout the pump’s service life. No special tools are needed—just follow the manual instructions to realign the impeller quickly and accurately.

The benefits are substantial, with a positive impact on sustainability and plant management:

• no need to disassemble the pump: the operator works from the outside;
• fast intervention: adjustment in under 1 minute, precise and repeatable over time;
• constant efficiency: ideal hydraulic flow and high performance thanks to the always-optimal gap;
• reduced maintenance costs: less time, fewer shutdowns, fewer errors.

Field application: maintenance of a K+ ENERGY pump in a lifting station

Imagine a wastewater lifting station equipped with a KCA pump from the K+ ENERGY series, with a twin-blade open impeller and FIXING SYSTEM.

After years of continuous operation, the pump undergoes routine maintenance: mechanical seal replacement and bearing inspection. Once the work is done, the pump must be reassembled and the optimal impeller–suction disk gap restored.

With a traditional system, the process would require shutting down and disconnecting the pump, completely disassembling it to access the impeller, manually adjusting the distance, and finally reassembling and restarting it. Estimated time: at least 2–3 hours, with risks of error and the need for workshop transport and specialised personnel.

With FIXING SYSTEM, the operator adjusts the impeller wear disk directly on site, from the outside, in less than a minute, and immediately restarts the pump.
In dry-pit installations, there’s not even a need to disconnect the pump from the pipework, as the adjustment nuts are fully accessible without emptying the tank.

The result? No extended downtime, reduced costs, restored efficiency.
A technological evolution that transforms a complex task into a fast, safe, and sustainable procedure.

Discover the KCA pumps of the K+ ENERGY series, equipped with FIXING SYSTEM.

Take-home message

Impeller wear disk adjustment is essential to maintain long-term pump efficiency and energy sustainability, helping reduce the product’s Carbon Footprint.

FAQ — FIXING SYSTEM and the impeller wear disk adjustment

What is impeller wear disk adjustment?
It is the operation that keeps the optimal gap between the impeller and the suction wear disk, ensuring maximum hydraulic efficiency.

Why is it important for pump efficiency?
If the gap varies, the fluid no longer enters the impeller at the ideal angle, reducing performance. It’s pure fluid dynamics: even small variations influence efficiency.

How often should the adjustment be performed?
There is no fixed schedule. It depends on operating hours, fluid characteristics and the presence of solids or abrasives. With aggressive liquids, disk wear makes adjustment necessary sooner or later.

What are the signs that adjustment is needed?
Reduced flow or head, increased energy consumption, or a general drop in performance.

Does adjustment require pump disassembly?
With FIXING SYSTEM, no: it is performed externally by acting on three nuts—no pump disassembly required.

Which models feature FIXING SYSTEM?
KCA submersible pumps of the K+ ENERGY series equipped with a twin-blade open impeller and a suction wear disk requiring periodic adjustment