Hiline Steel comprises a traditional range of pre-insulated steel pipe systems that are perfect for district heating and cooling networks.

A rigid, bonded pre-insulated steel pipe system in accordance with EN253. Suitable for district heating, cooling and special applications, it will accept temperatures up to 140°C continuous. Available in metric and imperial sizes – from 20mm to 1,200mm NB, it is supplied in 6 and 12 metre lengths with options for difussion barriers and insulation thicknesses in Series 3, 2 and 1.

Service Pipes

Metric - Seamless Pipe Certified seamless steel pipe manufactured in accordance with EN 10216-2 Grade P235 GH, EN 10216-1/A1 Grade P235 TR1 & P235 TR2, DIN 1629 Grade St 37.0

Metric - Seamed Pipe (Welded) Certified seamed (welded) steel pipe manufactured in accordance with EN 10217-2/A1 Grade P235 GH, EN 10217-5/A2 Grade P235 GH, EN 10217-1 Grade P235 TR1 or P235 TR2, DIN 1626 Grade St 37.0

Technical Specifications

	Hiline Steel
Maximum Continuous Operating Temperature	+140°C
Peak Operating Temperatures	+152°C
Thermal Conductivity	0.022W/mK
Thermal Insulation (S3,S2 and S1)	PUR / CFC free

Hiline Steel is certified welded carbon steel pipe manufactured in accordance with EN 10217-1:EN 10255 Grade S195T Heavy gauge or Medium gauge (formerly BS1387) & EN 10217-1:API5L Grade B/X42 Schedule 20 or Schedule 40.

Efficient Insulation in Series 3, 2 or 1

A key component in the efficiency of the Hiline pipe systems is our choice of CFC-free polyurethane foam to provide excellent levels of insulation – in accordance with the demands of the EN 253 standard. Available in Series 1, 2 and 3 thicknesses. By increasing the thickness of the insulation, significant cost savings can be made for the system operation.

Available with Diffusion Barrier

Hiline Steel systems are available with a foil diffusion barrier layer between the casing and the PUR foam insulation. This improves the system's performance over its lifetime by preventing the gas in PUR foam insulation from slowly diffusing through the outer casing and being replaced by air.

Robust and Adaptable Joints

The Hiline Steel service pipe is joined by welding. The HDPE outer casing can be joined using the proven Hiline range of wrap-around heat-shrink or electro-fusion couplings to ensure the very tightest of joints to protect against the ingress of ground water.

Complete System

Hiline Steel has a comprehensive range of pre-fabricated bends, tees, fittings and accessories that enable it to be adapted to meet all possible configurations.

Hiline Steel - Single

Size	OD	Casing (Series 2)	Casing (Series 3)
	d [mm]	D [mm]	D [mm]
20	26.9	90	110
25	33.7	110	125
32	42.4	125	140
40	48.3	125	140
50	60.3	140	160
65	76.1	160	200
80	88.9	200	225
100	114.3	225	250
125	139.7	250	315
150	168.3	315	355
200	219.1	355	400
250	273	450	500
300	323.9	500	560
350	355.6	560	630
400	406.4	630	670
450	457	630	710

Hiline Steel - Twin

Size	OD	Casing (Series 2)	Casing (Series 3)
	d [mm]	D [mm]	D [mm]
20	26.9	140	160
25	33.7	160	180
32	42.4	180	200
50	60.3	225	250
65	76.1	250	280
80	88.9	280	315
100	114.3	355	400
125	139.7	450	500
150	168.3	500	560
200	219.1	630	710

Engineering and Design Support

Design and Stress Analysis

There are many factors that will affect the long-term integrity of a pre-insulated pipe system. Correctly identifying and dealing with the potential for thermal expansion of the pipe system is a critical element of the design process and we employ state-of-the-art sisKMR specialist stress analysis software. This package allows us to configure the pipe routes to keep the thermal expansion within safe limits and conform to the requirements of the EN 13941 standard for Design and installation of pre-insulated bonded pipe systems for district heating.

Stress Analysis Example

Something as simple as adding in an unplanned branch connection can seriously impair a system’s ability to cope with the huge forces exerted on the pipe from thermal expansion. To put it into context, a 200-metre length of DN250mm pre-insulated steel pipe, heated to an operating temperature of 120°C will expand by around 150mm – exerting a stress of some 171MPa – the equivalent of 52 tonnes.

Please contact us to find out more and access our advanced stress analysis services for your project.

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Training and Support

As manufacturer, it’s important to us to ensure that our systems deliver exceptional performance throughout their working life. Therefore, we have established an array of world-class support services that help our clients every step of the way.

CPD Programme

CPV Ltd is CIBSE-accredited provider of CPD courses for Pre-insulated Heat Network Design and Specification

Electronic Surveillance Systems

We offer full a range of systems and supporting services for the main types of surveillance technologies, including the Nordic, Brandes and HDW systems.

CarboSeal Relining System

We are the UK representatives of the innovative CarboSeal relining system for buried heat networks. This enables failing networks to be repaired without the need to excavate the entire sections of pipe.