PREMANT district heating pipe

Filling in the pipe trenches

Surrounding material (sand)

• Compactable washed sand, max. particle size 8 mm (0 - 8 mm)

• Finest particle component ≤ 0.25 mm, not more than 8% if possible

• Friable or smallest possible loam component

As an alternative, so-called cyclone sand/sludge sand, particle size 0 - 1 mm, is permitted (the 'waste' from washed

sand). Crushed glass is not permitted as a substitute for sand with PREMANT district heating pipe (it is allowed for

FLEXWELL).

Embedding the pipe in sand (as per Trench Profile sheet)

• Coverage over crown of pipe - at least 10 cm.

• Compaction – very important!

• The sand must be compactly bedded in or compacted by hand, with suitable implements (such as a spade or

pick-axe handle) in layers between, below and next to the pipes. No cavities must be created.

Important: Do not damage the sealing strips and pipes!

Residual in

fill of the pipe trench

• The rest of the trench must be

filled in with layers of compactable material, such as excavated material and/or fine

gravel which must be well compacted. Local regulations govern the use of excavated material and the minimum

thickness of the

fine gravel layer.

• To compact the material, use a vibrator providing max. 100 kPa pressure/unit of area. Earliest compaction: from 30 cm

coverage of pipe crown. Remember: install pipe warning tape and any protective pipes (not over the pipes)

(approx. 30 cm above pipe crown).

• Top layer: use humus or HMT according to regulations.

If coverage is insufficient (< 60 cm) and in zones with heavy traffic loads, pressure distribution plates must be installed

over the sand layer to relieve pressure on the pipes.

In general, all construction and safety regulations must be followed.

PRE 6.502

17.1.2025 BGP

Subject to technical changes