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The HAS-System - innovative fitting welding system

The HAS-System - An innovative fitting welding system

Since 2015 the company Henze is part of the Krah group. At this year’s Krah Community Meeting the new generation of the HAS fitting welding system was presented by Henze.

The HAS-Fitting is:

• suitable for branches at all kinds of helically wound pipes.
• suitable for branches at direct extruded pipes too.
• available from OD 125 mm until OD 225 mm
• easy and quick to assemble
• especially designed for requirements of sewer pipe systems.
• available in polyethylene (HDPE) and polypropylene (PP)
• same durability as the main pipe system

Weiterlesen ...

Waste water heat recovery

Heating, cooling and energy saving with helically wound pipes (Energy from wastewater and warmed up soil)

There is a new market in the energy sector for manufacturers of helically wound pipes. Besides the classic diversion of wastewater, you can now also recover the wastewater’s energy with helically wound pipes. The wastewater and the pipe surrounded warmed up soil are a huge useful source of heat. The available support hoses around the helically wound pipes form a huge heat exchanger. Due to a heat transfer medium (brine or water) that flows through the support hoses, you can withdraw the heat energy from the wastewater and soil or you can store redundant heat energy ,that is being left over from building cooling, in the soil.

Waste water heat recovery

Weiterlesen ...

House connections flange (HAS) for large pipes


The Krah Community Member Henze GmbH offers his patented House Connection Solution HAS-160/225 to all Krah Community Members (Patent No. DE 102005051560B4) and to all large plastic pipe users (PE and PP pipe systems).

Finally, a quick, secure and cost effective solution for house connections of large plastics pipes is available. The complete installation of the HE-HAS will be done from outside, so the installation can be done under operating conditions. No manual „hand-extrusion welding“ is anymore required, but a special heating element fusion system is used, according to DVS2207.

The HE-HAS house connection is available in two connection sizes: DN160-SDR17,6 and DA 225-SDR17,6. So other pipe materials, like PVC, PP can be jointed easy. The HE-HAS house connection can be done on solid wall pipes, according to DIN8074/75, DN/EN 12666, DIN16961, EN13476, ASTM F894, NBR7373 and PAS.

Connection pipe DA 160 HAS
Connection pipe DA 160 HAS
Clean finish from the inside
Clean finish from the inside

Collector sizes are:

>= DN/ID300 – maximum profile height/solid wall thickness = 85 mm
>= DN/ID600 – maximum profile height/solid wall thickness = 145 mm

During the installation process
During the installation process
On-site installation of the house connection
On-site installation of the house connection

THE HAS is approved for HENZE and KRAH pipes.

Installation procedure:

  1. A hole will be drilled in the pipe
  2. The tensile equipment will be inserted through this hole into the main pipe
  3. The existing hole will be made conically
  4. A heating element will be inserted
  5. After the fusion temperature is reached, the heating element will be removed
  6. The HE-HAS house-connection will be inserted and the fusion pressure will be build up
  7. After cooling, the inner parts of the house connection will be scalped off, so that the main pipes has a smooth surface again.

The average installation time is only 15-20 min.

The new house connection HE-HAS has the following advantages:

  • Very cost effective
  • Quick and easy installation
  • Long life time
  • Welded technology
  • 100% water tight
  • No leakage during soil movements, thanks to welding
  • The connection can be done during an operating line

Prices for the welding equipment (HE-HAS-WE) can be obtained on request (on purchase or renting basis).

HAS Equipment for the construction siteHAS Equipment for the construction site

Beside the HE-HAS-WE welding equipment you need only the HE-HAS house connection parts.
List prices are between 60,00 EURO-100,00 EURO/pcs.

Connection pipe DA 160 HAS
Connection pipe DA 160 HAS
During the installation process on-site
During the installation process on-site

For any further technical or commercial information please contact us.

Henze GmbH
Dipl.-Ing. Andreas Wittner
Joesef-Kitz-Str. 9
53840 Troisdorf

Management of agricultural pipeline in Japan

1. Background

All over Japan we have huge agricultural fields to cultivate rice, vegetables, fruits and other crops. Major parts of the pipeline project were developed between 1968 and 1985 by the National development project. Since then over a century passed and the infrastructure became too old. Major problems of our pipelines are leakages, cracks, collapses and corrosion. This is not only harmful to the agricultural facilities but also to the farmer’s property.  For the stock management of agricultural pipelines, both human capacity and financial capacity is used.

Agriculture - cerealsAgriculture - cornAgriculture

2. Current situation

Next to the agricultural pipelines for farmers, tunnels, pipeline siphon systems by Fiber reinforced plastics mortal, steel pipes, ductile irons and concrete pipes exist in Japan.

Concrete junction fail

Leakage problems occurred in PC pipes, steel pipes and fiber reinforced plastics mortal pipes. The map shows at which part of the pipe the accident exactly happened. According to an investigation report by Mie prefecture, there were 51 accident-cases on pipelines until 2012. In particular within 5 years, they had a total of 25 accidents; a further accumulation of similar incidents can be expected.

Furthermore, in 1994, 2001 and 2009 leakages even led to an outage of water supply for a longer time and thus affected human activity tremendously.

From 2003 to 2011 a governmental research team investigated the given conditions of the main pipelines intensively by evaluating the concrete, neutralization tests, measurement of joint defection, EMF measurement, non-distractive inspection and drilling investigations. The result showed corrosion, abrasion and crack propagation due to degradation over time.


3. Problem

3.1. Fiber reinforced plastics mortal pipes

We found leakage problems especially in the joint section at fiber rein forced plastic mortal pipes (600DN) underneath the road. They were not able to transport 100% of the liquids for agricultural purposes any longer. Moreover, a car accident happened due to leakage underneath the road.

Vehicle collapsed due to junction failure in concrete pipe Concrete junction failure

3.2. PC pipe

We also faced troubles with PC pipes (1350DN) when the ground collapsed due to its leakages and formed a sinkhole. When agricultural, but especially sewer pipes, burst like this, most likely a secondary disaster follows due to contaminated soil or groundwater.

Ground collapse Ground collapse

4. Investigation

4.1. Cause of trouble (Fiber reinforced plastic mortal )

It was confirmed by these investigations that the soil conditions were significantly softened, uneven settled and also showed stress concentration on the fitting and smaller collapses (see picture below) after such a collapse.

Broken concrete pipe Concrete pipe abrasion

4.2. Cause of trouble (PC pipe ) 

Additionally it was confirmed by the surveys that the water quality was contaminated by erosive free carbon dioxide. The carbonation of the cover coat mortal is reducing the pipe wall thickness. As a cause of degraded PC steel wire, the pipes cracked and collapsed.

The water quality decreases due to erosive free carbon dioxide contaminated. Concrete abrasion

5. Conclusion

Especially for agricultural uses, it is very important to utilize pipes with a significant longer life time. It is striking that we need a complete modification to replace our oldest facilities with modern ones in order to provide safe water for agricultural uses. The new ones need to have a sufficient lifetime. Back in the days, we used fiber reinforced plastic mortal pipes, PC pipes, ductile iron and steel pipes.

However those are not durable enough for our needs.

Exclusively with polyethylene pipes we can ensure (or guarantee) the required lifetime and quality for our pipe systems.

Polyethylene pipes retain their characteristics for up to 100 years and longer. PE-pipe was already used for gas applications and as water pipelines around the globe. This is the time to use PE-pipes for agricultural uses.