Why are SMARTFLEX sumps made in two pieces?

The sump ships as two HDPE parts, which saves transport volume and protects it in transit, and are then joined by electrofusion on site, which gives a sealed chamber.

How is a tank sump checked for leaks?

NUPI states that tank sump tightness can be tested on site with a vacuum test during every installation step.

What load can the composite manhole covers take?

They are class C250 (up to 25 tonnes) to EN 124. The 36 inch size can reach class D400 (up to 40 tonnes).

NUPI SMARTFLEX Tank & Dispenser Sumps

Overview

SMARTFLEX sumps are polyethylene chambers that sit over the tank manway (tank sump, model S22TS) or under the dispenser (dispenser sump, model S21DS). NUPI builds them in two HDPE parts that are joined on site by electrofusion, using the same welding units as the pipework. The two-piece design ships in less space and protects the sump from damage in transport and storage, while the welded seam gives a sealed chamber once installed.

Tank sump tightness can be checked with a vacuum test at each step of the installation. One-piece tank and dispenser sumps are also made, and there are tank sumps with a thicker wall for difficult ground such as high groundwater, alluvial soil or poor backfill. The 2026 catalogue lists tank sumps with long risers, lid mounting kits, spare lids, dispenser installation kits and piping fixing bars.

On top, SMARTFLEX composite manhole covers replace heavy steel covers. They are rated class C250 (up to 25 tonnes) to EN 124, and the 36 inch cover reaches class D400 (up to 40 tonnes). NUPI states the surface grips better than metal when wet, dry or worn, that one person can lift it safely with the ergonomic lifting tool, and that the top surface has an estimated 15-year life. Polyethylene skirts fit the cover frames and stack for transport. Apex supplies and installs the full sump and cover package in Lebanon.

Key features

Electrofusion HDPE tank sumps (S22TS) and dispenser sumps (S21DS)
Two parts joined on site by electrofusion for a sealed chamber
Compact two-piece shipping protects the sump in transport and storage
Tank sump tightness can be vacuum tested at every installation step
One-piece versions and thick-wall tank sumps for high groundwater or poor backfill
Composite manhole covers class C250 to EN 124; 36 inch cover up to class D400
Better slip resistance than metal covers; single person lifting with the NUPI lifting tool
Stackable polyethylene skirts that fit the cover frames
Accessories include lid mounting kits, spare lids, dispenser installation kits and fixing bars

Questions

SMARTFLEX sumps and manhole covers: common questions

Why are SMARTFLEX sumps made in two pieces?: The sump ships as two HDPE parts, which saves transport volume and protects it in transit, and are then joined by electrofusion on site, which gives a sealed chamber.
How is a tank sump checked for leaks?: NUPI states that tank sump tightness can be tested on site with a vacuum test during every installation step.
What load can the composite manhole covers take?: They are class C250 (up to 25 tonnes) to EN 124. The 36 inch size can reach class D400 (up to 40 tonnes).

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All SMARTFLEX fuel piping system

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Pipe-in-pipe secondary containment with a continuous, monitorable interstitial space.

NUPI SMARTFLEX tank sump with fuel pipes sealed through the sump wall by entry boots

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Electrofusion and composite seals where pipes and cables pass through sump walls.