Can the BRAWOLINER® be used in pressure pipes?

We had a BRAWOLINER® DN 100 with BRAWO® I tested for internal pressure resistance as an example. In the test, the BRAWOLINER® DN 100 without an old pipe withstood an internal pressure of 9 bar for over 300 hours without failing.

The data is based on a test, no further testing was carried out for use in pressure pipes.

We recommend checking the suitability of each individual case and agreeing on the application with the client.

Can the BRAWOLINER® system be used to rehabilitate pipes in the filling station sector?

The BRAWOLINER® system has no approval for use in filling stations. In addition to our DIBt approval, we have had our products tested by the LGA in Nuremberg for resistance to exposure to oil/fuel. 

The tests were carried out in accordance with the applicable standard.

This is not tantamount to an approval for the filling station sector. However, the tests at the LGA together with our DIBt approval for underground waste water pipes (Z-42.3-362) cover the essential aspects. The two test reports, which show that our BRAWO® I and BRAWO® III resins fulfil the requirements regarding chemical resistance, can be found in the download area on our website www.brawosystems.com

Can the BRAWOLINER® system be used to rehabilitate pipes in the swimming pool sector?

This application is not covered by our approval and we therefore advise against it.

Is the BRAWOLINER® system approved for use in water protection zones? 

There is no approval for use in water protection zones. Our systems are officially approved by the German Institute for Construction Engineering (DIBt) and have therefore passed the environmental impact assessment. 

We recommend coordinating any use in water protection zones with the local authorities.

Is the film/coating an integral part of the BRAWOLINER® rehabilitation system? 

In response to your inquiry regarding a detached inner film on an installed BRAWOLINER®, we can tell you the following:

The PU coating acts as an installation aid during the installation of the liner. On the one hand, the coating protects the user from direct contact with the resin used during the impregnation of the liner; on the other hand, the coating acts as a membrane, enabling installation with air/water.

Once the liner has cured, the film or coating has already fulfilled its purpose, but remains in the lined pipe for the sake of simplicity.

If, contrary to expectations, the inner film or coating comes loose, it can be removed using a suitable tool.

The functionality of the rehabilitated pipe is guaranteed despite the removal of the inner liner, as this does not act as an integral part of the liner.

When tested by recognised testing institutes, the coating is not considered an integral part of the liner. It is assumed that the coating will be worn away by abrasion over the course of its service life.

For example, the coating is destroyed beforehand during a leak test in accordance with DWA-A 143-3 (cut into in a grid shape), as the liner (matrix of resin and textile carrier) alone must be leak-proof.

Also when determining the short-term E-modulus, the coating thickness is not included in the calculation of the wall thickness, as this does not contribute to the stiffness of the liner.

In this respect, it can be assumed that the functionality of the rehabilitated pipe is guaranteed despite the removal of the internal coating.

How does hose liner rehabilitation differ from coating processes such as spraying/brushing?

During the spraying, centrifuging and brushing processes, a layer of resin is applied to the inside of the old pipe as a coating. The inside of the old pipe must be cleaned so that it is completely free of dirt and grease that have a separating effect. The cleaning effort is correspondingly high. Furthermore, the coating does not prevent the progressive deterioration of the old pipe material. According to the recommendation for action "Rehabilitation of building drainage" from the VSB – Association of Certified Sewer Rehabilitation Consultants, the service life of coating processes (spray, centrifugal or brush application) has not yet been defined in the technical regulations due to the market launch approx. 5-10 years ago. Long-term findings are not yet available.

The hose liner is considered a rehabilitation method and has an economic service life of 50 years according to generally recognised technical standards. When installing a hose liner, a new plastic pipe is created in the old pipe. The old pipe is thus completely replaced by the hose liner. The pipes also have to be cleaned when using the hose liner method, although minor residues of dirt and grease do not affect the installation and service life. The first hose liners were installed around 50 years ago and long-term experience is available.

Can pipes in biogas plants be rehabilitated with BRAWOLINER®?

We have no experience of rehabilitating pipes in biogas plants.

Chemically speaking, in addition to the specified concentration of sulphuric acid and hydrogen sulphide, highly concentrated sulphuric acid may also be present here and there. Our BRAWOLINER® system is not resistant to concentrated sulphuric acid. Together with the bacteria present in the biogas plant and the temperature level, microbial corrosion can also occur in addition to chemical corrosion.

Our system has not yet been tested for this special case.

We advise against rehabilitating the described pipe with our BRAWOLINER® system.

What is special about the BRAWO® ShortLiner and is the system an approved system? 

The BRAWO® ShortLiner system is a method for the high-quality repair of partial damage in sewers and pipes in the diameters DN70 – 200.

BRAWO® ShortLiner consists of the BRAWOLINER® 3D, the BRAWO® SRR epoxy resin and the Bendy Packer including accessories. It is characterised in particular by a very high degree of flexibility. Repairs can be carried out in a closed construction method, even in difficult sewer and pipe runs as well as dimensional changes and bends. 

The repair process does not yet have DIBt approval as such, but the proven carrier material, the BRAWOLINER® 3D, is already described and included in several approvals from the German Institute for Constructional Engineering. The scope of application extends to the rehabilitation of waste water pipes, which can be installed both underground and inside buildings. The recommended 2-component epoxy resin system BRAWO® SRR is also based on approved 2-component epoxy resin systems, which have been tried and tested for years in the rehabilitation of waste water pipes. Only the type of installation differs from the existing approvals.

What is special about the BRAWO® connection collars and is the system an approved system? 

The rehabilitation of defective pipe unions is a major challenge. BRAWO® SYSTEMS offers the perfect solution for main pipes from DN 100 to DN 150 and inlets from DN 70 to DN 150.

With the Bendy Packer and flexible collars, even complicated inlets in downpipes can be rehabilitated quickly, cost-effectively and reliably. BRAWO® connection collars can also be used to easily reconnect inlets to pipes that have already been rehabilitated.

The BRAWO® connection collars are included as a supplementary procedure in the approvals Z-42.3-362 (rehabilitation of underground waste water pipes) and Z-42.3-499 (rehabilitation of waste water pipes inside buildings). BRAWO® SRR is a further development of the approved 2-component EP resin systems, which has been optimised in terms of processing and curing time. The optimised version has not yet been added to the existing approvals.

BRAWO® Connection Collars

BRAWO® SRR

Can the BRAWOLINER® be installed in PE-HD pipes? 

The rehabilitation case of an underground PE-HD pipe mentioned by you can be carried out with our BRAWOLINER® system. 

The rehabilitation of PE-HD pipes with our epoxy resins and UV light-curing resins is approved by the building authorities for underground pipes. Domestic PE-HD pipes are also an object of approval.

Compared to other pipe plastics, PE-HD has a high coefficient of linear expansion. During the rehabilitation of old pipes installed inside buildings, care must be taken to ensure that ambient temperatures are neither too high nor too low in order to minimise thermal stress. We recommend cold curing at moderate and constant ambient temperatures in order to minimise the linear expansion of the old pipe in this application as well.

Can oval profiles be rehabilitated with the BRAWOLINER®?

The BRAWOLINER® rehabilitation system is a process in which an extremely flexible carrier material is used in combination with various resin systems.

The high flexibility and elasticity of the carrier material means that the rehabilitation process can also be used for the rehabilitation of special profiles.

The BRAWOLINER® 3D is therefore also suitable for rehabilitating oval profiles:

In combination with BRAWO® III, the BRAWOLINER® 3D DN 200-300 can be used in the 200/300 oval profile and the BRAWOLINER® 3D DN 300-400 in the 250/375 oval profile.

This results in laminate thicknesses of 4.8 mm in 200/300 oval profile and 5.6 mm in the 250/375 oval profile.

The possible installation depths are determined in accordance with data sheet DWA-M-144-3 (Table C.2, Material characteristic group 2).

The rehabilitation of oval profiles with the BRAWOLINER® is possible and has already been carried out in measures (see report LINK).

Can copper pipes be rehabilitated with the BRAWOLINER®?

The material of the old pipe is not of primary importance when assessing its ability to be rehabilitated. Firstly, the old pipe fulfils the function of a casing for the BRAWOLINER®, which forms a new pipe in the old pipe. Our DIBt approvals list all common pipe materials that are usually used for waste water pipes. Other pipes and applications must be checked on a case-by-case basis to determine whether they can be rehabilitated. For the copper pipe, tests with BRAWO® I have shown that copper pipes can be rehabilitated with the BRAWOLINER® system with moderate temperature changes. 

Can (Geberit Silent) PP pipes be rehabilitated with the BRAWOLINER®?

The material of the old pipe is not of primary importance when assessing its ability to be rehabilitated. Firstly, the old pipe fulfils the function of a casing for the BRAWOLINER®, which forms a new pipe in the old pipe. Our DIBt approvals list all common pipe materials that are usually used for waste water pipes. 

If the pipe is installed with sleeves as a way of compensating for expansion, we recommend curing the hose liner at a temperature in the range of the average operating temperature of the waste water pipe. To prevent the old pipe and liner from sticking together, we recommend using a preliner. We recommend the use of BRAWO® III in order to minimise the resulting temperature increase during curing.

Can asbestos cement pipes be rehabilitated with the BRAWOLINER®?

The repair of asbestos cement pipes with hose liners in underground areas and with diameters ≥ DN200 is approved by the Institute for Occupational Safety and Health (IFA) as a low-emission process under the number BT 61.

The Pipe Rehabilitation Association (RSV) has published a recommendation for action for old pipes with smaller diameters and waste water pipes installed inside buildings. This can be accessed via the following link: https://rsv-ev.de/asbest-rohre-sanieren

BRAWO® SYSTEMS has also drawn up a recommendation for action. This can be found under the following link: https://www.brawosystems.com/en/downloads

Can drinking water pipes be rehabilitated with the BRAWOLINER®?

We advise against using the BRAWOLINER® system in drinking water applications.

Can ventilation ducts be rehabilitated with the BRAWOLINER®?

Please send your enquiry to info@brawosystems.com. 

Can gas pipes be rehabilitated with the BRAWOLINER®?

We advise against rehabilitating gas pipes with the BRAWOLINER®, as the evidence for the rehabilitation of pressure pipes is not available.

Why have creases formed in the cured liner? Is the quality of the liner impaired by the creases?

Depending on the condition of the old pipe, the installation method chosen and specific boundary conditions, wrinkles of varying severity may form in the laminate. The following factors influence the severity of the wrinkles:

• Radius and degree of the bends
• Undersizing of the liner in relation to the pipe's internal diameter
• Installation with or without a calibration hose
• Type of calibration hose used
• Inversion pressure and speed
• Curing pressure
• Pipe misalignment

Folds or surface irregularities that are within the limit values do not constitute a defect. They do not impair the operational suitability, stability or tightness of the rehabilitated system. In the case of folds or surface irregularities that exceed the permissible limit values, an individual case assessment must be carried out.

The limit values are defined differently in the three sets of regulations for in-situ curing hose lining DIN EN ISO 11296-4, DWA-A 143-3 and DWA-M 144-3. RSV information sheet 1.1 "Renovation of sewers and sewer pipes with in-situ curing hose lining", chapter 8.2 "Visual inspection", shows the limit values including explanations.

https://rsv-ev.de/merkblaetter-detailansicht/merkblatt-schlauchlining

When using BRAWOLINER, wrinkling is not usually to be expected in straight pipe runs. Exceptions prove the rule: if the circumference of the liner is greater than the circumference of the old pipe (inside), wrinkling may occur.

The selected rehabilitation method can also influence the result:

• If a hose liner with a "closed end" is installed, the material can move "freely" and adapt optimally to the geometry of the old pipe. Creasing, if any, is very minimal.
• If the liner is installed with an "open end" using a calibration hose, the flexible carrier material can no longer move as "freely", which may result in slightly more wrinkling.

This is more or less pronounced depending on the type of calibration hose used.

How can creasing be reduced or avoided? What can be done about it?

The best results are achieved when the hose liner used is undersized in comparison to the old pipe. Our BRAWOLINER® 3D products demonstrate advantages in use, even if there are no dimensional jumps in the old pipe.

Tips & tricks for installation with as few folds as possible:

• The use of BRAWOLINER DN 125 or BRAWOLINER 3D DN 100-150 in old pipes with a dimension of DN 150 means a low risk of wrinkling.
• Installation with a "closed end" = low risk of creasing (note: additional effort may be required to open the liner in areas that are not accessible).
• For installation with a calibration hose: Use a flexible calibration hose of the largest possible size (e.g. Airbagliner®).
• Slow inversion with sufficient pressure to allow the liner to adapt to the pipe geometry.

Can rehabilitation be carried out at ambient temperatures below 5 °C?

In principle, renovation with the BRAWOLINER system is not recommended at air and ground temperatures below 5 °C.

When carrying out hose liner rehabilitation at ambient temperatures below 5 °C, the material, air and ground temperatures must be taken into closer consideration during processing. 

Material temperature:

For the BRAWO I/III/SRR/RR 2K epoxy resin systems, we recommend tempering the components to approx. +13 - 15 °C before processing. 

For the light-curing resin systems BRAWO UVPox and BRAWO LR, we recommend tempering to approx. 20 °C before processing. For optimum tempering of the resins, storage in a climate-controlled cabinet is recommended.

We specify an air and substrate temperature of +5 - 30 °C as the processing conditions for the BRAWOLINER system. This means that the material is tempered in accordance with the recommendation before renovation and can be optimally processed in this temperature range during impregnation and further processing steps.

Air and substrate temperature:

In addition to the material temperatures, the temperatures in the sewage pipe and the substrate surrounding the sewage pipe also play a role in the renovation. At air temperatures below 5 °C, temperatures above 5 °C may be present in the sewage pipe to be renovated, so that renovation can be carried out.

For 2K epoxy resin systems, hot curing with water or steam is recommended at low ambient temperatures to ensure complete curing.

Can sewage pipes in commercial kitchens be rehabilitated using the BRAWOLINER® system?

This application is outside the scope of the approval. We cannot make any general statements about the influence of large quantities of hot waste water with temperatures > 60 °C, as can occur in commercial kitchens.

The suitability of the system should be assessed for each individual requirement. 

Please feel free to contact us if you have any questions. 

Can culvert pipes be renovated?

Culverts can be rehabilitated using the BRAWOLINER system. Of course, the conditions on site, especially the requirements for pipe statics, must be taken into account.

Can sewage pipes in the food industry, such as sewage pipes in breweries, dairies or cheese factories, be rehabilitated using the BRAWOLINER system?

All our resins are resistant to domestic sewage in accordance with DIN EN 1986 and as part of the approval test for the DIBt.

In addition, the resin systems exhibit good resistance to other chemicals.

Chemical resistance depends primarily on the resin used. The following link provides lists of the chemical resistances of BRAWO resins:

https://www.brawosystems.com/downloads/datenblaetter/technische-datenblaetter-harz/

Please contact us for further information.

Can light liquid separators be rehabilitated with the BRAWOLINER system?

See petrol station refurbishment Petrol station refurbishments.

How do I take liner samples correctly? What should be considered when taking test samples?

For quality assurance on construction sites, an accredited testing institute is often required to check the material properties of a sample from house connection pipes. This measure serves to ensure that the materials used meet the technical requirements.

Detailed information on the proper collection of samples can be found in our document "Information on sample collection for the purpose of checking material properties", which is available in the download area.

What types of damage can be repaired using the BRAWO RLC method?

See FAQ entry Repairable damage patterns. 

What is the maximum length of house connection that can be rehabilitated?

The decisive factor is the length of the BRAWO Magnavity hose. The sum of the distance from the manhole to the junction with the main sewer and the rehabilitation length of the house connection pipe should not exceed 50 m.

Example: 

Shaft 3 m

Junction with the main sewer 20 m

Renovation length of house connection pipe 10 m

Total 33 m --> OK

Manhole 3 m

Junction with main sewer 40 m

Renovation length of house connection pipe 20 m

Total 63 m --> not possible

Up to what line gradient can the BRAWO Remote LC method be used?

The BRAWOLINER is always installed against the gradient using the BRAWO Remote LC method. Normal gradients can be overcome without any problems. It is important that the liner is constantly pressurised during the inversion and curing process and is pressed against the old pipe wall.

Is one shaft sufficient, or are two shafts required as access points for the BRAWO Remote LC method?

Ideally, two shafts should be available as access points. If the distance between the start shaft and the inlet of the house connection pipe is short, one shaft can also be used as an access point.