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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.

Sewage pipes for argentinean Provinces

Project Description

Under the program for the Development of Northern Argentinean Provinces: Infrastructure Water and Sanitation, financed by the Interamerican Development Bank, the Program Execution Unit conducted the bidding process and award of the International Public Tender No. 01/13 for project: Streamlining of Pumping Plant Drive and Effluent Treatment Station - Santiago del Estero whose bid is on 27 November 2013. On held January 13, 2014, the InterAmerican Development Bank (BID) reported no objection to the recommendation for award of contract.

This integrated urban sanitation project involves the expansion of sewage lying over the construction of a sewage liquids treatment plant. It provides for expanding the number of new connections in 14,493 units, which would add to the existing 30,560 units. The length of the extension needed to achieve network is estimated at 425.9 km.

Location of the works within the city of Santiago del EsteroLocation of the works within the city of Santiago del Estero

The new pipeline will run from the station EB1 by Dr. Degano, Independencia, Av. Dr. Victor Alcorta heading south to the main drainage canal south street that runs through Los Lapachos. From there change direction by 90°, to take on the left side to its in the Viano channel mouth to cross it and continue along the left side of channel until turn at 90° to go to inlet of future treatment plant.

New and existing drive pipe layoutNew and existing drive pipe layout

This is a line 4250 meters of pipes that will be subjected to a maximum pressure of 3 kg/cm², for which the use of a hydraulic line of 1100 mm inner diameter and 6 kg/cm² nominal design pressure was determined.

Technical Offer

The constructor consortium called Krah America Latina to develop an alternative to the original offer, which was conceived in ductile iron or HDPE ISO4427, with butt fusion joint; but both alternatives were not adapted to the limitations of the work, in the first case because it is imported goods, expensive and very long delivery times supplies and in the second, of hard work in the trench, to be carried by urban areas and collapsible soils and high water tables.

For this, Krah America Latina made two offers, one using the PE/GF technology and the other with PE100 using the DIN/PAS 1065: 2007 standard. For this he made the following comparison:

Offer in comparisonOffer in comparison

After hard negotiations, the use of the first alternative was decided and went on to perform the mechanical and structural design of the pipe.

Mechanical and static calculations

While main pipeline will work at a maximum pressure of 3 kg/cm², the conditions of employment demanded that the pipes had 6 kg/cm² maximum allowable design pressure. So we proceeded to perform mechanical calculations according to the following table:

Various calculationsVarious calculations

All calculations were based on ISO 161 standard. At the same time, structural calculation was performed. For this Marston-Spangler theory stated in recommendations of AWWA M55 standard is used; then the calculation is added box.

Finished pipes are waiting for their useFinished pipes are waiting for their use

Various calculations
Various calculations

Finally, the pipes were designed under these concepts and specifications and conditions are as follows:

Various calculations

Work site

The work began in October 2014 and is scheduled for completion by September 2015. Shipments are made from Krah America Latina factory located in Buenos Aires and travel more than 1000 km to reach the work site in northern Argentina.

Work siteWork site

All joints were made using the unique system of electrofusion by Krah. Training courses were held and operators of construction consortium were prepared; regular visits to monitor the process are also performed.

Training of employees and monitoring the construction site Training of employees and monitoring the construction site

At the date of issuance of this report, the work is in full swing, following the planned schedules.

Construction site of the new sewage system Construction site of the new sewage system

Gustavo Mastelono beside the krah pipes

Pipes and manholes for Landfill-Applications


The control of gas and fluids in landfill application requires safe and applicable pipe-systems.
Due to environmental risks, the requirements for the raw-material and all finish and semi-finish products are much higher than for standard sewer applications. Also for welding and fabrication the quality-requirements are significantly higher. Special local approvals for raw-material, product, producer, welders and fabricators are often needed to simply enter the market. 

For more than 30 years High Density Polyethylene (PEHD) has been successfully used in landfill-applications. Especially the modern bimodal types of PEHD are the perfect material for the challenges we face in landfills and in contact with hazardous fluids and gases.

The excellent chemical resistance of polyethylene against a multitude of acids, lyes and organic hydrocarbons is a strong argument for using Polyethylene in Landfills.

Read more ...

HENZE Double-Wall-Tanks with tank-heating

HENZE is one of the market-leading manufacturer of large diameter plastic pipes. The pipes, made out of Polyethylene or Polypropylene are used for applications in water- and sewage systems and as industrial application as well. The spiral wound pipes can be produced either with a solid or profiled wall as structured pipes.

Especially the double wall structures enables HENZE to provide a high quality and security standard for industrial applications and interesting solutions for process-engineering (double wall tanks, heat- exchanger etc.)

The following brief-report shows the special application of storage- and treatment tanks, made of Polypropylene, for a bitumen-emulsion in road constructing.

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