The mounting of pump-sets is a key issue when installing pump units: even minor errors in configuration can result in non-compliant solutions. Below, I explain what the new edition of UNI 11292 specifies regarding the mounting of pump-sets (PUMP-SET).*
Table of Contents
Why the installation of pump-sets is a critical issue
When it comes to fire suppression pump-sets, mounting is not just a “mechanical” detail: it is an integral part of how the unit operates over time. The stated goal is to prevent the transmission of vibrations to the building’s structure and to keep the pump unit stable, without losing alignment.
In practice, the mounting system must be designed to support the unit’s operation, not just to “hold it in place” during installation.
UNI 11292: Effective Date and Reference Point
The new edition of UNI 11292 took effect on February 14, 2020. The explicit reference for the methods of securing pumping units (PUMP-SET) is section 6.6 of the standard, titled “Fastening Systems.”
This is the guideline to follow when determining the support and anchoring solution for the room.
Basic Requirement: Foundation and Load-Bearing Capacity
The facility must have a support surface (foundation) for the pumping unit capable of ensuring adequate resistance to the static and dynamic loads of the unit itself.
This requirement is the foundation: even before discussing brackets, anchors, or other solutions, a suitable foundation is needed to support the pump unit.
Anchoring/Cementing and Vibration Control
To prevent vibrations from the unit from being transmitted to the building’s structure, appropriate anchoring systems must be provided, or the pump unit must be set in concrete (see Figure 3).
Furthermore, the mounting system must have mechanical properties that allow it to withstand the unit’s vibration during operation. Therefore, simply “anchoring” it is not enough: the solution must be compatible with the unit’s vibrational behavior during operation.
Stability and Alignment Over Time: What a Fastening System Must Ensure
Section 6.6 also clarifies an often-overlooked requirement: the fastening system must ensure:
- stability of the pump unit;
- Alignment of the pump unit over time.
This means that testing should not be limited to the initial installation phase: the solution must remain effective over time, throughout the unit’s service life.
Be aware of areas with seismic characteristics
The rules require that installations in areas with seismic characteristics be carefully evaluated.
This section does not provide any further operational details; however, the message is clear—the installation context affects the choice of fasteners and must be specifically taken into account.
Avoiding Loads on Flanges: The Role of Supports
In addition to foundation and vibration considerations, UNI 11292 also requires attention to system design: loads on the pump flanges must be avoided by installing appropriate supports.
In other words, the mounting and alignment must be set up so that the pumps are not “loaded” onto the flanges due to improper configurations or supports.
What is a pump unit (PUMP-SET) according to the standard?
To correctly interpret the regulations governing the installation of pump-sets, it is essential to understand what is meant by “pump unit.”
The definition (section 3.15) states thata pump set is an assembly comprising:
- a pump with its motor and coupling system;
- any base;
- command and control center.
This makes it clear that the “part” that needs to be properly secured is the PUMP-SET as a whole, not just the pump.
Operating Rules and Practical Implications (What Is Not Permitted)
Given that each individual pumping unit (PUMP-SET) must be secured independently to the support surface, it follows that:
- Each PUMP-SET must be individually secured to the support surface;
- The fastening must be done using anchors directly embedded in the concrete;
- The pump units must not transmit vibrations to the building’s structure.
Based on these points, the text draws some clear operational conclusions:
- It is not possible to use floating sheet-metal floors supported by metal profiles attached directly to the building’s structure;
- It is not possible to use compact pressurization units in which the individual PUMP-SETs are mounted on an additional common base fixed to the floor;
- Anti-vibration mounts cannot be used under the frames of individual PUMP-SET units.
The final criterion is explicit: only PUMP-SET units that are independent of one another may be installed; they must be secured individually to the concrete support surface and comply with the distances specified in the rules.
Example of a Correct Solution (Figure 3)
The example indicated as correct isthe anchoring of the PUMP-SET to the concrete support surface, as specified in UNI 11292:2019 (see Figure 3).
At the same time, examples to avoid are cited, including:
- Mounting PUMP-SET units on a floating floor supported by metal profiles (not permitted);
- Mounting with vibration dampers (not permitted).
Conclusion
According to the report, the installation of pump-sets requires a clear approach: a suitable foundation, independent anchoring of each pump-set with concrete anchors, control of vibration transmission, and attention to flange loads through supports. Furthermore, installations in areas prone to seismic activity must be evaluated with particular care.
