DuoSafe® FLEX is engineered for applications where long, continuous lengths of small-diameter double-contained pipe are required. It is ideal for point-to-point dosing applications in water treatment where multiple dosing points may draw from a single chemical storage unit. The system uses high-quality flexible hose manufactured as a double-contained product in a single extrusion process. It is supplied in standard coil lengths of up to 300 metres, cut to a specific shorter length or specially produced in a longer coil where the project requires it. Connections between lengths and at termination points are made using a dedicated range of rigid PVC-U fittings.
Key Features of DuoSafe FLEX
DuoSafe FLEX combines a chemical carrier hose with an outer containment layer in one flexible product. This allows installers to create long pipe runs with fewer connections than a conventional rigid double-containment system. Its compact design, flexible construction and purpose-designed fittings make the system well suited to chemical dosing, water treatment and waste treatment installations where space or access may be limited.
Double-Contained Construction
The inner hose carries the chemical, while the outer hose provides secondary containment should the carrier develop a leak. Both layers are formed as part of a single extrusion process rather than being assembled as two separate pipes on site. This design helps contain escaped media and gives operators an opportunity to direct it towards a suitable leak-detection point. The outer hose is a containment layer only and must not be treated as a
pressure-rated carrier pipe.
Long Continuous Coil Lengths
Standard DuoSafe FLEX coils are available in lengths of up to 300 metres. IPS Flow Systems can also supply hose cut to shorter project-specific lengths, while longer special coils may be manufactured where practical.
Using one continuous hose can reduce the number of mechanical connections along a run. This is particularly useful for lengthy dosing lines or installations where joints would be difficult to inspect and maintain.
Aquachem and Hydrachem Hose Options
There are two hose types available within the DuoSafe FLEX range: Aquachem and Hydrachem. They have a similar external appearance, but the hose type is marked along its length for identification. Aquachem has a black plasticised TPU liner, nylon braiding for additional strength and a white PU outer coating.
Hydrachem uses a black LDPE inner liner, surrounded by a natural PE liner, braiding and a white PU coating. IPS Flow Systems generally holds Hydrachem in stock because its material construction suits a broad range of commonly transported chemicals. Chemical compatibility must still be confirmed for the intended media, temperature and concentration.
Small-Diameter, High-Pressure Capability
DuoSafe FLEX is intended for small-diameter chemical dosing lines where a flexible yet strong carrier hose is needed. The inner hose has a maximum working pressure of 10 bar when carrying water at 20°C. The outer hose is not pressure rated. Its function is to contain a leak from the inner liner and guide the escaped media towards a bund, cabinet or detection point. Pressure and temperature suitability should be checked against the selected hose size and chemical duty before installation.
Applications of DuoSafe FLEX
DuoSafe FLEX is suitable for point-to-point chemical transfer where the pipe route calls for a flexible, double-contained solution. Common uses include chemical dosing skids, water and waste treatment facilities, storage-unit connections and long runs between plant areas. The system can be particularly useful where rigid double-containment pipework would require numerous fittings or where the available space makes a conventional installation difficult.
Chemical Dosing Systems
The product is ideal for carrying treatment chemicals from a storage tank or dosing skid to the point of use. Its double-contained construction adds a secondary barrier around the chemical carrier hose. A continuous length can also reduce the number of connections within the system, helping to simplify installation and ongoing inspection.
Water Treatment Applications
DuoSafe FLEX is commonly specified for water treatment where there may be long distances between chemical storage and dosing equipment. Its small bore and flexible construction allow it to follow practical routes around existing plant. Hydrachem is often selected for these applications because it is compatible with many chemicals used in treatment processes. Compatibility should always be confirmed before the product is supplied.
Multiple Dosing Points
A single chemical storage unit may supply several dosing points across a facility. DuoSafe FLEX allows separate point-to-point lines to be run from the storage area to each location. This arrangement gives each dosing point its own carrier and containment route. It can also make individual lines easier to identify, isolate and replace when the system is properly planned.
Long Small-Diameter Pipe Runs
Coils of up to 300 metres allow long sections to be installed without intermediate connections. This can be useful across treatment plants, industrial sites and other facilities where a chemical line must pass through several areas. The hose has a minimum bend radius equal to eight times the outside diameter of the outer hose. This must be considered during route design to avoid kinking or placing unnecessary mechanical stress on the product.
DuoSafe FLEX Fittings and Connections
DuoSafe FLEX is designed as a point-to-point system and uses a limited range of purpose-designed fittings. The fittings are manufactured from PVC-U specifically for the hose construction, helping to provide secure connections without sharp edges that could damage the carrier liner.
Purpose-Designed PVC-U Fittings
The hose carries a warranty and is WRAS approved. However, only fittings designed for the DuoSafe FLEX system should be used. Standard hose tails can have sharp edges that cut into the liner. This may allow the transported
media to move behind it and cause delamination. Where an unsuitable fitting has been used, the product warranty may be made invalid. DuoSafe FLEX fittings are designed to match the hose bore without damaging the liner. A special stainless-steel retaining band secures the hose at the correct position. The fitting also has a tapered profile. As pressure acts on the connection, the hose tightens around this taper, supporting a secure mechanical joint.
DuoSafe FLEX Termination Fittings
The system uses three main termination fittings:
PHR**ADOS connects to the inner carrier hose only. It leaves the outer containment hose open for
connection to a bund or cabinet and provides either a spigot or female-threaded connection to the
carrier hose.
PHR**AOT connects to the outer containment hose only, allowing the inner carrier hose to pass
through. It provides a spigot connection for connecting the containment layer to a bund, cabinet or
associated fitting.
PHR**ADUAL connects to both the inner and outer hose. It seals the containment layer while leaving
a female-threaded connection on the carrier hose.
Two DUAL fittings should not be installed at opposite ends of a pressurised pumped system. If the
inner hose leaks, the sealed outer section could fill and become pressurised, potentially causing it to
expand or fail.
Retaining Bands and Installation Tools
A special stainless-steel retaining band secures the hose to each fitting. The band must be positioned
at the specified point on the fitting and closed using the dedicated installation pliers. Correct assembly matters because the retaining band and tapered fitting profile work together. Using the wrong band, placing it in the wrong position or applying it with an unsuitable tool may weaken the connection.
Leak Detection and Catch Pot Options
A true zone fitting is not available as a standard part of the range, but a catch pot can be used to provide a similar function. This normally consists of a grey PVC-U box with a clear lid, gasket and stainless-steel fasteners.
The outer containment hose connects to the outside of the box. The inner carrier hose is cut and connected inside it. Should a leak occur, the media can travel into the box for visual inspection or monitoring through separately specified mechanical or electrical detection equipment.
Catch pots may also contain valves, actuated valves, check valves and other connections. However,
they are splash-proof rather than pressure rated.
When used for leak detection, the box should be positioned at the lowest point of the pipe system.
When used as a zone point, it may limit the section of hose that must be replaced following a leak.
Where there is not enough room for a complete box, a tee arrangement may provide a smaller leak-
detection connection. This option can only be fitted at the start or end of the hose run.
DuoSafe FLEX Technical Resources
Review the DuoSafe FLEX technical resources for available hose sizes, material information, pressure limits, bend-radius requirements and fitting arrangements.
CTA: Download DuoSafe FLEX Technical Information
Need Help Specifying DuoSafe FLEX?
Speak to IPS Flow Systems for help selecting the right DuoSafe FLEX hose, carrier size, containment size and connection arrangement. The team can also provide guidance on chemical compatibility and installation requirements for dosing, water treatment and waste treatment applications.
Primary CTA: Enquire About DuoSafe FLEX
FAQs
What sizes is DuoSafe FLEX available in?
DuoSafe FLEX is available in a range of small carrier and outer containment hose diameters. The
correct combination depends on the required flow rate, chemical, working pressure and connection
arrangement.
Speak to IPS Flow Systems for the current size range and help matching the inner and outer hose to
your application.
What is the maximum working pressure of DuoSafe FLEX?
The inner carrier hose is rated to a maximum working pressure of 10 bar with water at 20°C.
Chemical type, temperature and installation conditions may affect the appropriate operating pressure.
The outer containment hose is not pressure rated. It is intended to contain leakage from the inner
hose rather than carry pressurised media.
What coil lengths are available for DuoSafe FLEX?
Standard DuoSafe FLEX coils can be supplied in continuous lengths of up to 300 metres. The hose
may also be cut to a specific shorter length.
Longer coils can be specially manufactured where the project requires them, subject to the selected
hose size and production availability.
What is the difference between Aquachem and Hydrachem DuoSafe FLEX hose?
Aquachem uses a black plasticised TPU carrier liner with nylon braiding and a white PU outer coating.
Hydrachem has a black LDPE carrier liner, a natural PE liner, braiding and a white PU coating.
IPS Flow Systems normally stocks Hydrachem because it covers many common chemical-transfer
duties. The most suitable type should still be selected by checking material compatibility with the
chemical, concentration and operating temperature.
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