PolyTank – Research project for the development and

HESSEL Ingenieurtechnik

Tagung Kunststoffe im Anlagenbau, 25.-26. Februar 2014, München

PolyTank – Research project for the developmentand validation of an automated ultrasonic systemfor non -destructive testing of extrusion welds in PE-storage tanks

Lars Simros, Johannes Grieser; HESSEL Ingenieurtechnik GmbH; Roetgen

Title

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PolyTank Project

• Objectives

• Benefits

• Test methods

• First results

• Summary

Content

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Project funded by the EU under the 7 ResearchFramework Program for small and medium -sized enterprises

Kick off: November 2012Duration: 2 yearsFinancial volume: 981.000€

PolyTank Project

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Development of an automated, non -destructive test method for testing extrusion welds in PE tanks by ultrasonic tests and the verification of the ultrasonic test resultsby creep rupture tests.

PolyTank Project

Aim:

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Development of flaw acceptance criteria



• Chem Resist Ltd (Chem Resist) - UK• Technology Assistance BCNA 2010, S. L. (TAB ) - Spain• Acutech Ltd (Acutech) - Greece• Innovative Technology and Science Limited

(InnoTec) - UK • TWI Ltd - UK• Hessel Ingenieurtechnik GmbH - Germany• Health and Safety Laboratory (HSL) - UK• Univar UK Ltd (Univar) - UK• NIKK The Netherlands Institute for Plastic Knowledge

- Netherlands

Project participants

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• Development of an automated, non-destructive test method for testing extrusion Welds in PE tanks.

• Determination of the critical flaw size and the crit ical contamination level for the investigated welded joi nts based on creep rupture tests.

• Construction of a prototype ultrasound inspection system and demonstration in field trials

Objectives

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Benefits

• No draining and cleaning of the storage tank or ves sel• No venting of the tank or vessel• No shutdown time during production• Reduction of health risks• Reduction of catastrophic failures

Examination of the full volume of the weld from the outside surface of the tank

Cost savings

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LS1

Slide 7

LS1 Lars Simros, 09/01/2014



One ultrasonic device for all existing welds in a tank.

General conditions

Tested wall thicknesses: 15, 25 and 40mm

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Project specification

� Fracture path related to

the fusion plane for the

flaw types to be assessed

� Reference weldwithout failure orcontamination

� ΣΣΣΣ 120 welds

Investigated welding defects in the poly tank project

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Doppel V butt weld

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σσσσσσσσ



Quelle: Schwaben-Kunststoff Chemietank- und Apparateb au GmbH&Co.KG Augsburger Straße 42 86863 Langenneu fnachDeutschland

Pipe outlet weld

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σσσσ



• Outside fillet weld at cylinder/bottom joint

Source: Schwaben-Kunststoff Chemietank- und Apparateb au GmbH&Co.KG Augsburger Straße 42 86863 Langenneu fnachDeutschland

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Weld at cylinder bottom



Preparation of welds

Test samples

• 15mm and 25mm extruded sheet natural colour )*• 40mm extruded sheet black colour )*• 110x10mm pipe black colour

Yellow welding wire was produced in order to allow visual distinction of the fracture path.

)* supplied by Röchling Plastics, Haren

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Simulation of water drops, fingerprints, etc. simulated by separating surfaces (aluminum plate)

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Preparation of welds



Cold welds are generated by no pre-heating of the m aterial

Deflected hot air

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Preparation of cold weld



Preparation of welding defects

The welding robot provides identical welding condit ions

Welding extruderRobot

Fillet weld

Welding rod

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� Mechanical tests

� Creep rupture tests

� Of the double-V butt weld.

� Of the fillet weld at pipe outlet

� Of the fillet weld at cylinder/ bottom joint

� Test methods in the PolyTank project

Prüfverfahren

� Non destructive testing (NDT)

� Ultrasonic inspection

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Tagung Kunststoffe im Anlagenbau, 25.-26. Februar 2014, München18

Test fluid

Weight

Time recording

Creep rupture test

Double -V

butt weld

Thermal insulation

Lever arm

Circulating pump

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Double-V butt weld after testing

Reference weld

Brittle failure outside the fusion planein the parent material

Fusion plane

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Cold weld

Failure inside the fusion plane

Fusion plane

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Double-V butt weld after testing



Control unit

Data record

Universaltestingmachine

Sample (Pipe outlet)

Test bath

Temperaturesensor

Constant load

Heatexchanger

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Creep rupture test



Pipe outlet after testing

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Reference weld



Reference weldBrittle failure outside the fusion plane in the parent mat erial(„tank wall“)

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„tank wall“

„pipe“



Tagung Kunststoffe im Anlagenbau, 25.-26. Februar 2014, München24 24

Cold weld




Cold weld

Failure inside the fusion plane

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„tank wall“

„pipe“




Fillet weld cylinder/ bottom joint

Fillet weld

Source: Schwaben-Kunststoff Chemietank- und Apparateb au GmbH&Co.KG Augsburger Straße 42 86863 Langenneu fnach Deutschland

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Fillet weld

Liquid level

p = ρ · g · h

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Deflection line schematically




Internal pressure test (ISO 1167)

Cross sample (cruciform weld)

Fillet weld

Cylinder

Bottom

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Fillet weldBottom


Cylinder wall

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Fillet weld

Bottom

Cylinder wall

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Cruciform weld before testing




Cruciform weld after testing

Cracks in the parentmaterial

Crack in the filletweld

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Summary

• Reference welds are failing outside the fusion plane inthe parent material.

• Contaminated welds are failing partially or completelyinside the fusion plane.

• Reference welds can clearly be distinguished from contaminated welds.

• A similar result is expected by the ultrasonic investigations.

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PolyTank

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Acknowledgement:

The research leading to these results hasreceived funding from the European Union'sSeventh Framework Programme managed byREA - Research Executive Agency [FP7/2007-2013] under grant agreement no [313950].



Thank you for your attention !

More information at

www.polytank.eu

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Documents

PolyTank – Research project for the development and