Blutube® Operating Pressure / Temperatures

OPERATING TEMP ºC DESIGN LIFE YERAS PERMISSIBLE WORKING PRESSURE
BAR KPA PSI
-20º TO 20º 50 16 1600 235
 30º 50 14.1 1410 205
 40º 50 12 1200 175
 50º 50 10.2 1020 150
 60º 50 8.8 880 130
ABOVE RATINGS HAVE AN ADDITIONAL SAFETY FACTOR OF 2:1
Fluid at 20º C 50 25 2500 360

Temperatures quoted relate to constant temperature over a period of 50 years, rather than short term peak temperatures. Blutube can safely handle short term peaks in compressed air temperature up to 95deg C. Circumstances vary and each high temperature application should be checked by the technical department.

SAFETY FACTOR

At all rated pressures for compressed air as above Blutube is manufactured with a safety factor of 2. On a typical installation this gives an effective safety factor of 4 at 800 kpa/20deg C /50 years.

GUARANTEE

Blutube is manufactured to AS 4130/AS 4131 and is accordingly guaranteed for 50 years provided recommended design, installation and operating practices are adopted. As established from long term testing, Blutube may be operated continuously under pressure for up to 200 years at 20deg C.

CONDENSATE DRAINAGE

Condensate should be removed as soon as possible in a pipe system. A suitably sized compressed air dryer after the Air Receiver is a recommended method for removing condensate from the air supply. If a high short term requirement of dry air is required, then the dryer would be better installed prior to the Receiver. The good thermal characteristics of Blutube are a further advantage.  The system should be designed to minimise or eliminate harmful condensate from being discharged into air tools and equipment when dryers are not fitted. The recommended method is to install the dropper from the bottom of the branch or mainline with a short extra length of pipe extending below the outlet to form a water trap, this then terminating with a drain valve for the removal of condensate. Horizontal pipe can be sloped at a slight gradient to strategically positioned drain legs, outlet droppers can come off the top of the pipework to avoid precipitated condensate being discharged in the airstream.

UNDERGROUND PIPEWORK

Blutube is ideal for underground installation with its high strength characteristics and ability to absorb ground movement. It is recommended to lay pipework in sand, grade and install drain valves in strategic positions. Please refer to Technical Department for details.

HAZARDOUS AREAS

Corrosive chemicals
Blutube has excellent resistance to a broad range of chemicals and is ideal for use in many areas where corrosive liquids or atmosphere may contact the pipe. Compression fittings come standard in polypropylene construction with O-Rings of nitrile rubber and Split Grip Rings in Polyacetal. The Nitrile gives excellent resistance to oils in the compressed air. For aggressive chemical applications CPVC Split Rings and O-Rings in EPDM or Viton are available.  Fusion welded fittings provide a further degree of safety in these areas. User should verify compatibility of components with their application. Extensive compatibility charts are available.  Resistance to specifi c chemicals should be checked with Technical Department.

Explosive or ignitable atmosphere
Compressed air can carry static charges which may accumulate.  The user/customer/purchaser is responsible to identify any potential hazardous areas and to take necessary measures or precautions for complete safety. Information on protective measures is available with advice on your specific application.

HEAT SOURCES AND EXTERIOR PIPEWORK

Blutube is suitable for outdoor installation.  Industry best practice of shielding equipment and pipework from direct heat sources should be adopted to prevent excessive heat buildup. In the event that pipe is exposed to direct sunlight a surface layer forms over time creating a barrier which impedes further U.V. effects. As with all Polymer pipe systems exposed to direct U.V., there may be some reduction of impact resistance over time however longevity and pressure rating of Blutube is not affected.

SOCKET FUSION WELDED FITTINGS

Pipe and fittings are welded by socket fusion method to AS2033- 1980. Fittings comply with DIN16963. The fittings are heated simultaneously with pipe then joined to give an extremely strong weld of high pressure capability, fusing pipe and fitting into one integral piece. Made in Europe specially for compressed air pipe systems.

ELECTRO FUSION WELDED FITTINGS

Fittings for electro fusion comply with AS4129 and carry a standards mark licence under a Quality Assurance System in accordance with ISO 9002. The fittings incorporate a resistor in one of the terminals which is specific to that fitting. The automatic control box reads the resistor and sets and welds the correct time, avoiding operator error. Fittings are also labelled for barcode reading and manual setting times. Rising melt indicators confirm successful completion of weld.

COMPRESSION O-RING TYPE FITTINGS

Compression fittings manufactured under ISO 9002 Quality System and have Standards Mark Licence No 2018- AS4129.  Air seal is provided by a heavy duty O-Ring and pipe is securely held by split grip ring and nut. Extensive research and experience has confirmed our confidence in the range of fittings offered being of the highest quality and reliability. These fittings are approved by the manufacturer for compressed air applications and, whilst they are conservatively rated at PN16 (16 bar)/20degC/50 years for other applications, with a view to an additional safety factor for compressed air, we recommend these fittings for installations subject to conditions not exceeding 10 bar pressure at constant average temperature of 40degC.

THERMAL EXPANSION AND CONTRACTION PIPE CLIPS / PIPING LAYOUT

Blutube thermal expansion and contraction is 0.18mm per metre per Deg C. If pipework is to be subjected to thermal temperature change, expansion and contraction needs to be allowed for while system is being installed. Movement can be absorbed on changes of direction, elbows, etc. but on longer lengths the recommended installation principles as set out below should be adhered to. This movement is minimised if areas in which pipework is installed are heated or cooled and eliminated in constant temperature areas.

EXPANSION LOOPS

Install expansion loops at intervals of approx. 30-40m on long runs. For leg lengths refer to table below. It is general practice for loops up to BLUTUBE63 to span between purlins.

PRESTRESSING

Pipework can be prestressed, and particular note should be made of this when installation is carried out in cold conditions.
Presentening

Suggested L s Length (Metres)
20 0.5
25 0.6
32 0.7
40 0.9
50 1.0
63 1.2
90 1.8
110 2.0
160 2.4

PIPE CLIPS

Free axial movement of pipework should be allowed with any form of support. Pipework should be able to move on elbows, tees, etc.

Pipe Clips

ANCHOR POINTS

Anchor points are clips which don’t allow free axial movement. Anchor points can be used as shown to evenly spread the effects of expansion and contraction.

Anchor Points


Below: Working example of Ring Main showing typical expansion loops and anchor point positions for this schematic.

Example

Pressure drop – mbar per metre:
Note: A.N.R (Atmosphere Normale de Rerence) Standard Reference Atomsphere ISO R554 – 20degC 65% Relative Humidity 1013 mbar

Conversion:  1mbar=0.1kpa,   1l/s=2.1191cfm

How to use the compressed air flow chart.

Four quantities are involved in the use of this chart, these being air pressure, rate of flow, pipe size and pressure drop. Any one of these can be determined providing the remaining three are known.

Problem 1:
Air initially at 10 bar is being transmitted at a rate of 60 l/s free air through 20mm pipe.  What will be the pressure drop due to friction through 30 metres of pipe?
Solution:
(This example is plotted on the chart) From the point representing 10 bar at the top of the chart proceed down vertically to intersect with the horizontal line representing 60 l/s on the right hand scale. Proceed diagonally downwards, parallel to the guide lines to intersect the horizontal line representing 20mm on the left hand side scale. From this point proceed vertically to the pressure drop scale on the bottom of the chart and take the reading. The pressure drop is found to be approximately 17 mbar per metre of pipe or 510 mbar (0.5 bar) per 30 metres of pipe.

Problem 2:
10 l/s of free air is required at a pressure of 4 bar with a maximum allowable pressure drop of 140 mbar per 30 metres of pipe. What would be the recommended pipe size for this application?
Solution:
From the point representing 4 bar on the top axis of the chart proceed down vertically to intersect the horizontal line representing 10 l/s on the right hand scale. Proceed diagonally, parallel to the guide lines to intersect the vertical line from the bottom scale representing the allowable pressure drop of 140 mbar per 30 metres of pipe (Read 140/30 = 4.5). From this intersection point proceed horizontally to the left hand side of the chart. The point falls between 10mm and 15mm pipe sizes. The correct selection therefore, is 15mm pipe.

The Compressed Air System shall be Blutube, non-metallic, blue in colour, corrosion free, conforming to AS/NZS 4130/4131 and be made to PN 25 under an accredited AS 3902 Quality Control System.

Pipe

The pipe shall be PN 25 with a safety factor of 2:1; rated at 16 Bar / 20degC / 50 year design life and 8.8 Bar / 60degC / 50 year.

Fittings

All fittings shall be Blutube Socket Fusion, Electro Fusion or Compression style fi ttings which comply with Australian Standards as listed below. Blutube Socket Fusion fittings shall be made to DIN 16963 which shall be welded to AS 2033.  Blutube Compression fittings shall be either ‘O’ Ring or tapered seal to comply with AS/NZS 4129 and carry a Standards Mark Licence No. 2018 in accordance with ISO 9002.

Blutube Electro Fusion fittings shall comply with AS/NZS 4129 and carry a Standards Mark Licence under Quality Assurance System in accordance with ISO 9002. Fixing of pipe shall be of a type and spacing approved for use as per Blutube Technical Manual.

Breathing Air

Breathing Air and Medical applications
Blutube is suitable for breathing air and medical applications, Technical Department recommendations must be adopted. It is the user’s responsibility to provide and maintain supply air at a suitable level of purity for these applications.

Storage

Storage and transport
Pipe should be stored and transported straight and true.

Shipping Weights
Blutube20 0.9 Kg / 6m length
Blutube25 1.4 Kg / 6m length
Blutube32 2.4 Kg / 6m length
Blutube40 3.5 Kg / 6m length
Blutube50 5.5 Kg / 6m length
Blutube63 8.7 Kg / 6m length
Blutube90 18 Kg / 6m length
Blutube110 27 Kg / 6m length
Blutube160 55 kg / 6m length

Other uses

Blutube as detailed in this technical manual is also suitable for:
• High pressure Fluid to 25 bar
• Chilled Water
• Warm Water
• Inert Gasses
• Chemical Piping
• Vacuum Piping
Please refer to Technical Department for details.

Trading Terms

As part of a process of continual improvement, the Company reserves the right to upgrade or modify components from the description in this manual at any time without notice. Whilst due care and revision has been taken in preparation of this Manual, the Company takes no liability for accuracy of information contained herein.

No part may be reproduced in any way without written permission from the Company.  All Sales are subject to the Company’s Terms and Conditions of Sale. E & OE.