Rigid preinsulated pipes with a steel carrier pipe:

The production programme for preinsulated pipes with steel carrier pipes comprises a line-up of all preinsulated pipes, fittings and fixtures to be used in transmission of a heating medium and hot tap water in carrier pipes of diameters of:
  • for single pipes of diameters between Dn 20 and Dn 1200 mm;
  • for double pipes of diameters between Dn 20 and Dn 200 mm;
Every steel pipe is blast cleaned up to purity degree I prior to insulating.

ZPU Międzyrzecz system pipes and fittings come in composite units made up form:
  1. Single pipes – steel carrier pipe placed axially in a casing pipe made from high density hard polyethylene (PEHD) and a thermal insulation layer standard or standard-plus type made from rigid polyurethane foam (PUR) filling in the space between the pipes. They are manufactured in 6 or 12 metre sections. Preinsulated pipe and fitting ends are not insulated over a distance of 150 mm±10 mm in pipes of diameters up to Dn 200 mm, and over a distance of 200 mm±10 mm in pipes of diameters equal or above Dn 250 mm.
  2. Double pipes – two steel carrier pipes placed in a single casing pipe made from high density hard polyethylene (PEHD) and a thermal insulation layer standard or standard-plus type made from rigid polyurethane foam (PUR) filling in the space between the two steel carrier pipes and the casing pipe. They are manufactured in 6 or 12 metre sections. Preinsulated pipe and fitting ends are not insulated over a distance of 150 mm±10 mm. The spacing tolerance between the in-feed and out-feed carrier pipes measured at pipe ends ±1 mm, and when measured between two any points inside the double pipe unit is ±2 mm.

ZPU Międzyrzecz Sp. z o.o. preinsulated products meet the requirements of PN-EN standards:

253 – pipe unit;
448 – fittings;
488 – fixtures;
489 – joint assembly.


Depending on final use and the customer’s requirements the carrier pipe can be manufactured from the following materials:
  • seamless steel pipe, of material R-35; St37.0 and P235GH, compliant with standards ISO 9329, DIN 1629, PN-EN 10216-2;
  • seamed steel pipe, of material St37.0 and P235GH, compliant with standards ISO 9330, DIN 1629, PN-EN 10217-2; PE-EN 10217-5;
  • galvanised seamless pipe in accordance with PN-EN 10240, PN-EN ISO 1461, PN-EN 1179;
  • structural steel tubes intended to be fitted in mining shafts made from 18G2, R35, R45, R55, R65 or St37.0 compliant with ISO 9329, PN-EN 10224 in diameters ranging between Dn 20 and Dn 600 mm;
  • certified pipe made of: medium and high density polyethylene, polyvinyl chloride, copper, or other depending on end use and customer’s requirements.
Rigid polyurethane of a thermal conductivity coefficient PUR λ50 = 0,0244 W/mK foamed by means of cyclopentane is used as an insulating medium. The maximal operating temperature is 152° C. As the casing pipe the following are used:
  • for buried district heating utilities PEHD high density polyethylene.
  • overhead district heating systems are cased in SPIRO voral-type galvanised metal sheets in accordance with PN-EN 10327:2005(U) or aluminium sheets in accordance with PN-87/H-92833, and stainless steel sheet metal as well as special polyethylene pipe covered with an anti-UV layer.

ZPU Międzyrzecz Sp. z o. o. preinsulated products stand out from other manufacturers’ products due to these facts:
  • preinsulated units are manufactured in an environmentally friendly manner;
  • the steel carrier pipe is blast cleaned to purity class I prior to being insulated with foam;
  • we are the first manufacturer in Poland to use cyclopentane C5H10, which does not deplete the ozone layer;
  • we are a Polish manufacturer of:
    • heat shrinkable sleeves;
    • crosslinked heat shrinkable sleeves made from crosslinked polyethylene;
    • machine bent pipes;
    • machine bent elbows of diameters up to Dn 200;
    • resistance welded joints;
ZPU Międzyrzecz Sp. z o. o. can also supply any preinsulated elements a customer may request, e.g. individually specified bend angles and other elbow lengths, other possible arrangements of tee and reducing pipe outlet diameters. We supply preinsulated Y-pieces made from forged steel and with extendable arm in steel pipe and/or in HDPE casing pipe (without welds or fillet welds).

ZPU Międzyrzecz Sp. z o. o. offers a choice of joint types:
  • joint sleeves – A PEHD sleeve sealed with a heat shrinkable tape, N-type;
  • heat shrinkable – a heat shrinkable PEHD sleeve sealed with a heat shrinkable band, NT-type;
  • crosslinked heat shrinkable TS-type – a heat shrinkable crosslinked PEHD sleeve made from crosslinked polyethylene;
  • crosslinked heat shrinkable TS-type – a heat shrinkable crosslinked PEHD sleeve made from crosslinked polyethylene;
ZPU Międzyrzecz Sp. z o. o. preinsulated pipes and fittings can be furnished with any PUR insulation moisture detection system. As a standard our company provides pipe and preinsulated units with a pulse (reflectometric) leak detectors. Preinsulated units can also have embedded such moisture detection systems as Brandes system, HDW system or any such that he customer may require.

The system comprises wires embedded in the insulation layer. Such system, embedded in pipe and preinsulated units, signals emergencies at any point of the pipeline and allows to locate precisely a moist spot in the PUR foam insulation. Signal circuits, alarm devices and leak failure locators are included in a system.