Diab Foam Materials

DIAB ‘SOLUTIONS’ - SPRING 2007 - 2

The New Low FST Core Material from DIAB

Commercial aircraft interiors are a major application area for Divinycell F.

Train interiors is another major market for Divinycell F.

DIAB’s new manufacturing facility for Divinycell F is adjacent to the company’s existing plant in DeSoto, Texas.

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Divinycell F is a signifi-

cant breakthrough in core

material development,

offering low FST (fire, smoke and

toxicity) properties coupled with

good mechanical and processing

characteristics.

Developed by DIAB primarily

for the commercial aircraft and

public transportation markets, it

more than exceeds the USA and

European regulatory requirements

for aircraft interiors and the Euro-

pean train FST requirements.

Other key features include

superior damage tolerance, ex-

ceptional fatigue life, low water

absorption and excellent heat

ageing at 180°C (356°F). Chemical

resistance to the majority of aircraft

fluids is also excellent.

Divinycell F is compatible with

most common composite manu-

facturing processes up to 220°C

(428°F) cure cycles, including

infusion. When used with most

pre-pregs it does not require the

use of a film adhesive. It is also

compatible with most common

thermoplastic and thermoset resins

including the epoxies and modern

phenolics used by both aircraft and

train manufacturers.

With its superior fire properties

Divinycell F is ideal for aircraft

interiors including wall panelling,

ceiling modules, luggage bins and

doors/lockers. Its close cell struc-

ture makes it particularly suitable

for galleys and toilets.

It is also an excellent sandwich

core material for train and subway

interiors, exceeding as it does,

the new EN 45545-2 regulatory

requirements.

The new material will be manu-

factured in a dedicated production

facility that is close to DIAB’s ex-

isting DeSoto, Texas, operation.

Initially, Divinycell F will be avail-

able in three densities - 50, 90 and

130 kg/m3 (3.1, 5.6 and 8.1 lb/ft3)

and can be supplied in both plain

sheets and kit form.

High temperature resistance. (+220°C/-195°C).

● Excellent fire behavior. (Very low smoke & toxicity)

● Low water absorption.

● Excellent fatigue life.

● Superior damage tolerance.

● More processing friendly.

● No film adhesive required.


LOW DENSITY ADDITION TO DIVINYCELL HP RANGE

Thailand Facility EstablishedDIAB has enhanced its support

for the South-East Asian market by

establishing a new facility in Chon-

buri near Bangkok in Thailand. As a

result of setting up the new facility,

DIAB will be able to offer an even

faster response to customer needs

in Thailand, Malaysia, Singapore,

Vietnam, the Philippines, Laos and

Indonesia.

The new facility will not just be

a sales operation but will include

technical service personnel who will

be able to assist DIAB customers in

the region with the introduction of

new processing techniques such

as Core Infusion Technology™ and

‘ready to use’ core kits – both of

which have been pioneered around

the world by DIAB.

In addition, the new facility will

carry out finishing operations to

more closely meet the particular

core material requirements of the

region and specific DIAB custom-

ers.

Commenting on the new facility,

Johan Gralén, VP Sales & Market-

ing AAO, said “The investment in

the new Thailand operation follows

on closely from the establishment

last year of our Chinese facility

and the recent announcement of

the addition of a kit manufacturing

production unit in Shanghai. It is

a clear demonstration of DIAB’s

long term commitment to the Asian

market.”

DIAB’s new Thailand facility in Chonburi near Bangkok.

DIAB has expanded its Divinycell

HP range of core materials with the

addition of a low density version -

HP60. It offers all the advantages

of the existing HP range - excellent

mechanicals, high processing and

service life temperatures - yet with

its nominal density of just 65 kg/m3

(4.1 lb/ft3), it will allow further weight

reductions in advanced sandwich

composite structures.

The main application areas

for the new material will be the

wind energy and marine markets,

especially those companies using

prepregs.

The high compressive strength

and modulus of HP60 allows it to

resist the buckling loads expe-

rienced in wind blades whereas

its high service life temperature

makes it ideal for dark colored

decks and superstructures.

With its elevated process-

ing temperature of up to 140°C

(284°F), outstanding adhesion and

peel strength, Divinycell HP60 is

fully compatible with the majority

of epoxy prepregs. It can also be

readily used for closed molding

processes such as resin infusion

and RTM (resin transfer molding)

where high exothermic tempera-

tures can be encountered.

As with the other densities in

the range, Divinycell HP60 has

good shear strength and modulus

values. Similarly its shear strain fig-

ure clearly demonstrates its good

ductility and energy absorption

characteristics. HP60 also offers

good chemical resistance, excel-

lent insulation properties and is

self-extinguishing.

Wind energy will be one of the main application areas for Divinycell HP60.


MAR

INE DYNA CRAFT & DIAB

When leading Taiwanese

boat builder, Dyna Craft,

contemplated introduc-

ing closed molding technology

in order to increase production

without reducing quality, it naturally

looked at vacuum infusion mold-

ing. Other yards in Taiwan had

already gone down this route but

Dyna Craft was concerned that

with some of the methods on offer

the set-up was complex, a high

amount of consumables were used

and surface finish was often poor.

The company then evaluated

DIAB Core Infusion Technology™

and found that the set-up was

simple and consumable costs were

very low. As a result DIAB Techni-

cal Services in China was asked to

put together a complete program

to introduce the new technology.

The program began with an on-site,

five day, comprehensive training

course attended by Dyna Craft

production, engineering and man-

agement personnel that included

exhaustive training manuals in both

English and Chinese. By the end

of the session, Dyna Craft person-

nel were confidently producing

a variety of primary parts (floors,

bulkheads and tank tops) using

infusion.

While the training took place

DIAB Technical Services’ engineers

prepared the laminate design for

hull and deck of one of the smaller

vessels that the company builds.

The DIAB and Dyna teams then

communicated back and forth to

finalize the scantlings and set the

date for the first hull infusion.

InfusIng the fIrst hull

When all the materials were in

place and the equipment ready,

two DIAB engineers, together with

local distributor Port King, arrived

to oversee the set-up and infusion

of the first hull and deck - a five day

program. All ran smoothly and the

hull was infused on the evening of

the fourth day. The hull had a single

skin bottom and by removing the

CSM (chopped strand mat) content

from the laminate and replacing

some laminate with CFM ( continu-

ous filament mat) no surface flow

medium was required and it was

possible to place the resin lines

well apart. This allowed for a simple

set-up in the hull bottom area, with

few feed points and lines. The top-

sides were cored so only one feed

line was required along each chine

to infuse the hull all the way to the

shear line. Total infusion time was

Infusing the Perfect Partnership

about 100 minutes. On the fifth day

the fully-cored deck was infused

without any problems.

The yard has since completed

four vessels of this type. One of the

biggest gains has been the fact

that the hulls and decks are now

being de-molded with a high level

of finish and no print-through (even

on dark colored hulls) thanks to the

print barrier system introduced by

DIAB Technical Services.

Since the first infusion, DIAB

have been on site a further five

times in order to fine tune the pro-

cess and implement new ideas

such as kitting and re-usable lines

and connectors. The partnership

continues with the next stage be-

ing to look at infusing the stringers

at the same time as the hull. Also

Dyna Craft is evaluating this ap-

proach for its larger vessels which

range from the 15.5 meter (51 ft.)

Dyna Flybridge to the 23.5 meter

(77 ft.) Laguna.

www.dynacraftyacht.com

The hull molding at Dyna Craft ready to be infused.


AFRICAN CATS

When Dutch business-

man and experienced

sailor Gideon Goud-

smit couldn’t find a production

catamaran to meet his needs he

decided to start a company to

build his ideal boat. As a result Af-

rican Cats (Durban, South Africa)

was established to build pro-

duction catamarans that would

rewrite the ‘rule book’ in terms of

speed, handling, performance

and comfort.

In order to reduce weight

while at the same time increasing

structural strength, African Cats

has developed its own infusion

manufacturing system called Vec-

tor-K that uses lightweight/high

strength composite materials

(carbon, Kevlar, basalt and e-

glass reinforcements, Divinycell

core materials and epoxy resin).

As a result its sailing cats (which

range in length from 12.1 to 20.7

meters [40-68 ft.]) are almost

50% lighter than the competi-

tion. Although saving weight was

the primary goal, the company

maintains that safety has never

been compromised to achieve

it. All boats are CE certified by

ECB and, of course, a lighter boat

means a lower center of gravity

for added safety. In addition the

use of Kevlar in the hulls greatly

improves impact resistance.

African Cats light weight/high

strength philosophy is not just

confined to the main structure of

its cats. One example is where

African Cats has broken with

tradition by not using a gel coat

on the outer skins or a flow coat

on the insides of the boat. As

any experienced boat owner can

tell you a gel coat is a relatively

fragile covering, easy to scratch

and difficult to repair. Instead

of a gel coat, African Cats uses

a much tougher polyurethane

paint. Not only is it much easier

to color match and repair but it

also saves a significant amount

of weight - in the case of the

company’s 435 model over 500

kilos (1,100 lb.) - 12% of the total

weight of the boat!

Re-writing the ‘Rule Book’

An African Cat 435 which is now available in a fossil fuel-free version.

Continuous development is

very much the watchword at

the company. Last year African

Cats introduced the world’s first

fossil fuel-free, production sailing

yacht which uses a combination

of dual wind generators and so-

lar panels to charge its batteries.

With the lithium-ion battery op-

tion, the cat’s electric motor can

be run continuously for six hours

at 50% power. Top speed of the

13.16 meter (43 ft.) long vessel

is 8 knots under power and 20

knots under sail. Sailing at just

5 knots is sufficient to re-charge

the batteries.

www.africancats.com

MAR

INE


Since being established

in 1970 Faaborg Værft

has grown to become

Denmark’s leading builder of com-

mercial FRP vessels.

Initially the company concen-

trated on pleasure craft but over

a relatively short space of time the

emphasis was switched to fishing

boats and special purpose ves-

sels.

In 1979 Faaborg Værft took

over the Jupiter shipyard at Bogø

on Møn, together with the rights to

the boat type of the same name.

Over time it developed the Jupiter

models into various types of work

boats including inspection boats

for the German River Police.

The recession in the fishing in-

dustry has meant that a large part

of its production and repair work

in recent years has been directed

towards other areas. Typically

Faaborg’s customers have been

government and municipal authori-

FAABORG VAERFT A/S

ties such as the Danish Pilotage

Authority, the Danish Environmen-

tal Protection Agency, the Royal

Danish Navy and six of Denmark’s

counties.

Faaborg still continues to pro-

duce fishing vessels ranging in

length from 12 to 25 meters (40

to 82 ft.)

One of the company’s latest

contracts is from the Danish Naval

Material Command for the supply

of six Standardfartøj MK II patrol

ships that will replace the BARSØ

class vessels that have been in ser-

vice for over 40 years. Each ship

is 43 meters (141 ft.) long and has

a beam of 8.2 meters (27 ft.).

Delivery of the first ship to the

Royal Danish Navy will take place

in July this year with the remaining

five vessels being commissioned

over the next two years.

The hull, deck, superstructure

and interior of the vessels are

primarily FRP sandwich based on

Divinycell cores. Although Faaborg

is the prime contractor, it has sub-

contracted the hull moldings to

Kockums AB in Sweden (builder

of the Visby ‘Stealth’ Corvette).

After installation of the propulsion

system, the hulls are transported

to Faaborg Værft A/S for outfitting

and delivery to the Royal Danish

Navy.

www.faaborg-vaerft.dk

Two of the six 43 meter (141 ft.) vessels that Faaborg is producing for the Royal Danish Navy.

A Faaborg 36 fishing boat.

Denmark’s Leading Commercial FRP Shipbuilder


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MUNDAL BÅT AS

Sayer Moves to Core Infusion

Mundal Båt AS is one of Norway’s

leading builders of FRP sandwich

vessels. The company was es-

tablished in 1981 by brothers Atle

and Nils Landro who recognized

that the light weight/high strength

and corrosion resistant attributes

of composites were ideal for fish-

ing vessels.

To date Mundal has built and

delivered over 38 commercial

vessels using Divinycell sandwich

construction. In addition it has

re-built/expanded a further 15

vessels, again using sandwich con-

struction. It now offer vessels up to

33.5 meters (110 ft.) in length. The

company uses a variety of com-

posite manufacturing techniques

and has recently introduced DIAB

Core Infusion Technology™.

In addition to its commercial

boat building work, Mundal has

expanded its activities to include

the production of a variety of sand-

wich composite components for

offshore oil and gas and sub-sea

applications. These include guided

drogues and sub-sea buoyancy

units.

www.mundal.no

‘Bluefin’ a 27.1 meter trawler built by Mundal Båt AS.

Led by the well-known sailor-de-

signer-builder, Jon Sayer, Sayer

Yachting Services specializes in

custom design and construc-

tion. Based in Mooloolaba on

Queensland’s Sunshine Coast in

Australia, SYS has recently made

its first foray into infusion molding

with the production of two 12 meter

(39 ft.) race boats that have been

designed primarily for the Mel-

bourne to Osaka Double Handed

Yacht Race.

The original plan was to use

vacuum bagging but having at-

tended one of DIAB’s Core Infusion

Technology™ courses Jon Sayer

decided that infusing the boat and

thermoforming the core was the

way to go.

Engineering was by EMP Com-

posites and infusion processing

The Jon Sayer-designed and built 12 meter ‘Wasabi’ about to leave the yard.

support by DIAB Technical Ser-

vices. The first boat, ‘Ryujin’ was

launched in July 2006 whereas her

sister hit the water in December.

Commenting on the switch, Jon

Sayer said, “There is little doubt

that this is a clean and cost-effec-

tive method for this type of boat.

We managed to fully impregnate

the 12 meter hull halves with ep-

oxy resin in 40 minutes and the

‘one shot’ approach saved a lot of

secondary bonding operations.”

He added, “Our biggest success

in the process was the use of DIAB

GPC1 pattern foam to provide the

correct resin transfer properties.”

www.sayerdesign.com

TECH

NICA

L SE

RVIC

ES Sandwich Panel Impact Performance


Introduction

The main difference between

laminates manufactured us-

ing vacuum infusion versus

hand lamination is the fiber volume

fraction. There are well known and

verified theories for predicting

global stiffness and strength of

sandwich panels. These theories

together with the rule of mixtures

can be used to study the influ-

ence of variations in fiber volume

fraction. However, without empiri-

cal testing it is difficult to predict

impact performance.

The aim of this study was to

investigate the difference in impact

performance between sandwich

skins manufactured using infusion

and hand lay-up. A secondary ob-

jective was to evaluate whether it is

possible to predict impact damage

with a quasi-static test.

test Panels

Two sets of test panels were

made. For the first, the ‘hand’ and

infused panels had the same fiber

lay up in order to study the direct

effect of the different manufactur-

ing processes. In the second test

series the manufacturing method

was taken into account when de-

signing the fiber lay-up thereby

providing a more ‘real world’ com-

parison scenario.

All the test panels comprised

a 20 mm core of Divinycell H130

with glass skins. An infusion grade

polyester resin was used for all of

the panels in order to prevent any

differences in resin properties ef-

fecting the results.

The fol lowing coding has

been used for the glass fiber

lay-up: CSM=Chopped Strand

Mat. Q=Quadriaxial symmetrical

distribution. B=Biaxial symmetri-

cal distribution 0/90 direction.

The number denotes the weight

in g/m2.

first test series

In both cases the lay-up (im-

pacted surface downwards) was

CSM 450 / Q 800 x 2 / 20 mm H130

/ Q 800 x 2. On the hand laminated

panel the fiber volume fraction was

0.32 whereas with the vacuum in-

fused panel it was 0.43. The outer

CSM fabric, which was hand laid

on both panels, was 0.14.

The sandwich panels were

designed and manufactured to

meet the requirements for a typi-

cal bottom panel of a 11.6 meter

(38ft.) power boat, according to

the preliminary ISO standard. With

the infusion process, the skins are

usually specified with a lower CSM

content due to the good skin to

core bond.

second test series

Starting from the outside of the

hull the lay-up for the hand lami-

nated panel was CSM 300 / CSM

450 / B 600 x 2 / CSM 450 / 20 mm

H130 / CSM 300 / B 800 x 2. The

vacuum infused panel had a lay

up of CSM 600 / B 800 x 2 / 20 mm

H130 / B 800 x 2.

The outer CSM layer was hand

laid to simulate a typical skin coat.

The fiber volume fractions were

0.27 for the hand laminated panel,

0.39 for the vacuum infused panel

and 0.15 for the CSM fabric that

was hand laid on both panels.

Outer skin thicknesses were 2.7

mm for the vacuum infused panel

and 4.3 mm for hand laid panel.

DIAB Technical Services has recently undertaken a study to evaluate the variations in impact performance of sandwich panels produced by hand laminating and infusion.

Carl-Johan Lindholm, M.Sc., reports on the main findings of the study.

The two ‘impactors’ that were used to simulate impacts from sharp and blunt objects.


Impact testing

The impacts were carried out

using a five meter (16.4 ft.) high

test rig from which a sled was

dropped. It was possible to vary

the height from which the sled was

dropped and the mass of the sled.

The kinetic energy applied to the

panel was calculated by using the

velocity (just before the sled hit the

panel) and the weight of the sled.

Two impactors were used to

simulate an impact from a sharp

and a blunt object. The sandwich

panels were placed on a rigid

steel plate to ensure that just the

local effects of an impact could

be studied.

Quasi-static testing

The quasi-static tests were

made using an Instron universal

testing machine. During the tests,

the force and position of the cross-

head was recorded. From the force

indention curve the energy loaded

onto the panel was calculated.

One type of damage is the

visual de-laminated area. In this

case the Quasi-Static testing was

carried out by stopping the inden-

tion in steps of 1 mm. At the end of

every step the load was recorded

and the panel unloaded and the

de-lamination area measured.

Conclusions

Comparing the two types of

panels, hand lamination and infu-

sion, the size of the de-laminated

area from a spherical impact was

similar for both panel types. It can

be concluded that even if the outer

skin of the vacuum infused panel

is 36% thinner and 27% lighter

than the hand laminated panel,

the resistance against a spherical

impact is likely to be the same. A

possible explanation is that with the

spherical impactor the stress state

in the skin may be dominated by

membrane stresses.

The visual damage (see below)

seems similar on the both panels

apart from the fact that the vacuum.

Infused panel tends to give slightly

larger de-laminations in the prin-

ciple direction of the fibers. This

may be because the infused panel

contains less randomly distributed

fibers than the hand laminated

panel.

Since the tensile properties of

the skins are designed to be simi-

lar, no difference in performance

was seen. In the case of the sharp

impactor, the hand laminated panel

showed slightly less indentation

compared to the infused panel at

the same load. The reason for this

may be that the thicker skins of

the hand laminated panel perform

better when the stress state is

dominated by bending and shear

stresses.

It appears that results from

quasi-static testing can be used to

predict the indentation depth from

a sharp impact with reasonable

precision. The results achieved

with the spherical impactor are not

as accurate, but may be sufficient

to provide a rough estimate of the

likely ‘real world’ performance.

Regarding the de-lamination

area from the spherical impactor,

quasi-static testing may be used to

indicate the size of the de-lamina-

tion area. However this is only valid

as long as the skin has not been

penetrated in the test.

A copy of the complete study (which in-cludes the full test results) is available free-of -charge from DIAB Technical Services.

The set-up for the quasi-static tests.

The two panels on the left show a spherical impact at 150 Joules (left: infused panel, right: hand lay-up panel). The two panels on the right show a ‘sharp’ impact at 150 Joules (left: infused panel, right: hand lay-up panel).

MAR

INE


WERNER PADDLES - SIMPLY THE BEST

WINNER OPTIMIST

Werner Paddles (Sultan, Wash-

ington State, USA) is recognized

as the world’s leading producer of

paddles for whitewater, touring and

canoeing use.

At the top end of Werner’s

various offerings is its Performance

Core lines which feature paddle

blades constructed using pressure

molded technology.

The form of the blade is initially

defined by the foam core blank

which is precisely CNC-milled to

create the correct shape and cur-

vature. Carbon and, depending on

the model, Kevlar reinforcements

are laid onto the core using epoxy

resin. Then, for added durability,

Werner molds a layer of Dynel

around the edge and a double

layer in the tip where the paddles

are prone to abuse. The complete

assembly is then loaded into a

custom-built, heated press to cre-

ate the final blade. The end result

is a technical blade design that

displaces water for a significantly

lighter, buoyant feel on the water.

The added buoyancy is excep-

tional for enhancing rolls in aerated

water, allowing stable bracing and

reducing effort in long paddle out-

ings.

www.wernerpaddles.com

If there is one thing that the majority

of Olympic sailors have in common

is that they started their sailing ca-

reer in an Optimist. Sailed in over

110 countries by over 150,000

young people, it is the only dinghy

approved by the International Sail-

ing Federation for sailors under 16

years of age.

Although ‘Opies’ are produced

by many builders around the world,

the Danish company Winner Opti-

mists ApS, which was founded in

1965, is not only one of the most

experienced builders but also one

of the most successful with 15

World and 18 Europeans titles.

With Winner’s emphasis on

using only the best materials and

the highest standards of crafts-

manship, many would argue that

Winner produce the best GRP

Optimist. It is certainly the only

one that comes with a five year hull

guarantee. Vacuum bag sandwich

construction based on Divinycell

cores is used for the hull with DIAB

providing CNC milled core kits that

meet Winner’s exacting specifica-

tion. Each dinghy is checked by an

independent measurer who takes

120 separate measurements that

must be within ±1 mm.

www.winneroptimist.dk

The Choice of Today’s & Tomorrow’s Champions

A young sailor heading downwind in a Winner Optimist.

A Werner paddle with foam-cored blades in action.


Jupiter Plast A/S is one of the

world’s leading producers of

composite components for

the major wind turbine companies

and train rolling stock manufactur-

ers. From its original base around

the Danish island of Bogø, it now

has facilities in Germany, the

United States and China.

A long term user of DIAB sand-

wich cores, Jupiter Plast takes an

integrated approach when it comes

to the production of composite

moldings. This encompasses

component design, laminate en-

gineering and analysis (including

Finite Element Modelling), process

development and complete supply

chain logistics.

A typical example of the ben-

efits of this approach to Jupiter’s

customers is the extensive devel-

JUPITER PLAST

opment work it has undertaken

regarding nacelles (housings) for

wind turbines.

With the move to more power-

ful machines (2 MW plus is not

uncommon today), the nacelles

have become very large indeed .

The 2 MW for example is 4 x 4 x 15

meters (13.1 x 13.1 x 49.2 ft). The

cost of transporting such large and

potentially heavy components can

be very high.

Due to a combination of lami-

nate optimisation, removal of steel

reinforcements and the use of a

bespoke RTM Lite manufacturing

process, Jupiter has been able to

cut nacelle weight by more than

half. In addition, the nacelles are

quickly assembled from a series

of modular components using a

patented assembly system that

was also developed by Jupiter.

Jupiter’s role has even extended

to designing the special transport

stillages (seen below) that reduce

shipping volume and allow a com-

plete nacelle to be supplied to the

customer in ‘flat pack’ form. It is

estimated that the ‘nacelle optimi-

sation’ work undertaken by Jupiter

has halved transportation costs.

www.jupiterplast.dk

A batch of Jupiter wind turbine nacelles mounted on their specially designed transportation stillages.

Installation of Vestas V90 wind turbine nacelle and spinner.

A World Leader in Wind Energy & Train Components

WIN

D EN

ERGY

ARKTOS CraftThe Ultimate ‘Go Anywhere’ Amphibious Craft


TRAN

SPOR

T

A USCG approved 52-Evacuee ARKTOS Evacuation Craft under going pilot training in the US Beaufort Sea.

There are many vehicles and

craft that claim to have ‘go

anywhere capability’ but

none can get close to the per-

formance offered by an ARKTOS

Craft. These unique Craft, which

are designed and manufactured by

ARKTOS Developments Ltd. (ADL)

of Surrey, BC, Canada, have the

highest level of all-round amphibi-

ous mobility in the world. Due to

their unique design ARKTOS Craft

have an unsurpassed ability to

climb from water to ice and ma-

neuver through ice-rubble fields,

significant side slopes, steep

grades, muskeg, quicksand and

any other water transition zones.

The original concept was to

develop a craft that could evacuate

personnel from offshore oil pro-

duction facilities in temperatures

down to -50°C (-122°F) in mixed

water/ice conditions, land-fast

ice-rubble fields, shear-zone ice

and high winds on any ice surface

of the Beaufort Sea. Evacuation

is still one of the primary roles for

the ARKTOS Craft but today their

duties have been extended to

include fire fighting, geophysical

survey work and exploration in any

corner of the world irrespective of

the prevailing climatic condition or

the terrain.

ARKTOS Craft Enhancements The ARKTOS Craft concept

continues to be improved and

enhanced and today the mission

profile of the current evacuation

model includes evacuee survival

in the H2S gas clouds and burning

oil slicks that might be encountered

during the evacuation of bottom

founded oil rigs plus the ability to

remain afloat after damaging the

integrity of either of the hulls in ice

infested waters.

Successful tests of these en-

hancements, amongst others,

were required by the United States

Coast Guard (USCG) to approve

the 15.24 meter (50 ft.) ARKTOS

Craft for evacuation of 52 people

from bottom founded offshore

islands.

Although the existing 15.24

meter (50 ft.), USCG approved,

ARKTOS Evacuation Craft can

carry 52 evacuees or 5,000 kilo-

grams (11,000 lb.) of cargo through

the most severe terrain and up to

10,000 kilograms (22,000 lb.) of

cargo in open water, larger ver-

sions with a capacity of up to 150

evacuees are being developed.

Amphibious ARKTOS Crane Craft

and Amphibious ARKTOS Tugs ( to

tow Hover Barges) are also on the

‘drawing board’.

The ARKTOS Craft comprises

a permanently linked pair of sand-

wich composite hulls or units

as they are called. Each hull is

independently powered by its

own diesel engine. On ice or land

motive power is provided by the

tracks, while in water, propulsion

jets supply the required thrust.

A hydraulically powered ar-

ticulation arm links the two hulls,

or units.

Articulation control is achieved

by logic circuits operated through

a joystick allowing each unit to

operate at independent angles

with three axis of motion. This gives

ARKTOS Craft exceptional mobility

while moving across the interface

between dissimilar footings such

as the transition from water to ice,

land to ice, land to water, muskeg,

and land to quicksand. The ar-

ticulation arm also allows ARKTOS


Four ARKTOS Evacuation Craft on stand by on a man-made island in the Northern Caspian Sea that is seasonally surrounded by ice.

Fosieplast Moves To Infusion for Fire Truck Tank/Bodies

Craft to negotiate the irregular ter-

rain in ice-rubble fields, ice ridges,

abrupt drop-offs, side slopes and

most other hostile terrain.

The DIAB Technical Services

team has recently been heavily

involved in assisting ADL to re-

duce the weight and increase the

strength of the hulls, decks, struc-

tural-bulkheads, drive-wheel

boxes, nose idler-wheel boxes

and water-tight hatches, etc. par-

ticularly in terms of the crushing

and abrasive forces that can be

exerted when an ARKTOS Craft is

traversing ice floe formations. This

has involved re-engineering the

laminates (which now comprise a

combination of E-glass and Kev-

lar fabrics over a DIAB sandwich

core) and introducing DIAB Core

Infusion Technology™. As a result

of the new laminate specification,

ADL has removed the original steel

reinforcements without any loss of

structural integrity.

DIAB Tech Services also car-

ried out a series of flow modelling

exercises to determine the ideal

infusion set-up and was then on

site to assist the ADL production

team with the set-up and infusion

of the first hull, deck and structural

bulkhead moldings.

ADL has since produced a

further three unit sets of moldings

and reports that it is saving more

than one drum of resin per unit set

by using infusion.

www.arktoscraft.com

The complete rear end of of this fire truck is a sandwich composite molding.

Fosieplast AB (Arlöv, Sweden)

has been manufacturing

sandwich composite fire

truck tanks since 1977. Not only

are the sandwich tanks lighter and

stronger than an equivalent metal

unit they are also considerably

superior in terms of corrosion and

chemical resistance.

Although described as a tank,

the component that Fosieplast ac-

tually manufactures is much more

complex. In fact, it is (as can be

A tank/body in the final stages of manufacture.

seen here) the complete rear end

of the fire truck that is mounted

directly onto the chassis. Recently

the company has started to switch

from hand laminating to an infusion

process. This has multiple benefits.

The resulting laminates have much

higher fiber fractions than would be

the case with hand laminating and

therefore are stronger and lighter.

In addition, elapsed production

time is halved and the resulting

moldings have a much better sur-

face finish.

Another benefit of the process

for Fosieplast is that it now finds it

much easier to recruit personnel.

www.fosieplast.se


ULTRA-PORTABLE CARBON FIBRE SATELLITE TRANSMISSION DISHES

A rear view of the main dish that shows the special latching system.

INDU

STRY

The main dish and sub-reflector of the satellite transmission system.

Carbonia Composites AB

(Malmö, Sweden) special-

izes in the production of

high precision, composite compo-

nents using primarily carbon fiber,

specially-formulated epoxy resins,

Divinycell cores and a proprietary

resin transfer molding (RTM) pro-

cess.

For one of its major projects

it acts as a development partner

and supplier of components for a

new class of ground-breaking, ul-

tra-compact satellite transmission

systems. They are used by leading

broadcasters around the world as

well as several defense organiza-

tions including the US Special

Operations Command.

The transmission systems are

the smallest and lightest units

that are approved by all the major

commercial satellite operators. Key

design features of the units include

the ability to be carried and set up

in minutes by one person (who is

not expected to be a satellite com-

munications specialist) irrespective

of the location and the climatic

conditions.

To achieve the required levels

of signal accuracy (less than 3°

of arc), portability and reliability,

extensive use has been made of

carbon fiber sandwich compos-

ites for the main reflector, the sub

reflector and the transit case.

The requirement for the system

to retain its transmission accuracy

under potentially very difficult oper-

ating conditions (-40°C to +100°C

[-104°F to +212°F]) has meant that

the Carbonia components have

to be manufactured to an overall

tolerance of ±0.6 mm. (In fact, the

sub-reflector is made to accuracy

+0.05 mm.) Achieving this level of

accuracy is further complicated

by the need for the main 900 mm

diameter dish to be dismantled into

four separate pieces after use so

that it is truly hand-portable.

Carbonia also designed and

developed the special ‘latching

system’ that locks together the four

elements that make up the main

reflector (dish).

Such is the design of the sys-

tem that the four elements can be

locked together in seconds without

any adjustments being required or

for that matter allowed in case the

operator inadvertently introduces

errors into the system.

www.carbonia.se


SCHEMPP-HIRTH

A Schempp-Hirth Duo Discus. Photograph: J. Ewald.

AERO

SPAC

E

A Schempp-Hirth Discus-2c. Photograph: Wil Jannsens.

The name of Schempp-

Hirth Flugzeugbau GmbH

(Kirchheim unter Teck, Würt-

temberg, Germany) is synonymous

with success in competitive gliding.

Its sailplanes have so far amassed

a total of 26 world championship

titles (40% of all the world titles

awarded to date). Schempp-Hirth

gliders have also won countless

European titles and over 50 USA

national titles. Despite being in

business for more than 70 years,

the company continues to break

records and new ground in terms of

glider design and development.

In December last year in Ar-

gentina Klaus Ohlmann set a new

world speed record, averaging

306 kmh (190 mph) over a 500

km (310 miles) out and return in

a Schempp-Hirth Nimbus-4DM.

This was quickly followed in Janu-

ary by Sigi Baumgartl who set a

new speed record of 156.3 kmh

(97.12 mph) over a 750 km (466

World Class Performance for Over Seventy Years

miles) triangle in Namibia in his

Schempp-Hirth Ventus cM/15m (15

meter wingspan). Not to be out-

done by the men, Anja Kohlrausch

achieved a women’s world triangle

distance record of 1,019 km (633

miles) in a Ventus-2cxT/15m (15

meter wingspan).

Schempp-Hirth maintains that

its success is due to a combina-

tion of factors that include futuristic

constructions, high build quality, a

complete understanding of com-

posite materials and, last but not

least, highly motivated and expe-

rienced personnel.

The production of Schempp-

Hirth gliders began in a municipal

building yard in Göppingen, Ger-

many in 1935. In 1938 the company

relocated to its present site at

Kirchheim unter Teck. In the 1960s

the company quickly moved from

wooden glider construction to

composites.

Today, all Schempp-Hirth glid-

ers feature sandwich composite

wings based on Divinycell cores

in order to achieve a strong, light-

weight and aerodynamic structure.

The current range of gliders and

motor gliders comprises models

covering the 15 and 18 meter (50

and 60 ft.) wingspan Standard

Class (Discus), 15 and 18 meter

(50 and 60 ft.) wingspan FAI Class

(Ventus), a two seater (Duo Discus)

and the Nimbus open class.

www.schempp-hirth.com

www.diabgroup.com

DIAB is the world’s largest producer of structural foam core materials with production facilities inSweden, Italy, Lithuania, the USA, China, Thailand, Australia and Ecuador.

AustraliaTel +61 (0)2 9620 9999Fax +61 (0)2 9620 9900

E-m: [email protected]

DenmarkTel +45 48 22 04 70Fax +45 48 24 40 01


FranceTel +33 (0)2 38 93 80 20Fax +33 (0)2 38 93 80 29


GermanyTel +49 (0)511 42 03 40

Fax +49 (0)511 42 03 438E-m: [email protected]

NorwayTel +47 66 98 19 30Fax +47 66 84 64 14


UKTel +44 (0)1452 50 18 60Fax +44 (0)1452 30 70 31


USATel +1 (972) 228-7600Fax +1 (972) 228-2667


SwedenTel +46 (0)430 163 00Fax +46 (0)430 163 95


SandwichCompositeSledge

ItalyTel +39 0119 42 20 56Fax +39 0119 47 35 53


ChinaTel +86 (0)512 5763 0666Fax +86 (0)512 5763 0999


Pictured here is the first rigid, habit-

able sledge seen in Antarctica. The

brainchild of Brazilian, Julio Fiadi, the

‘capsule’ was engineered by Barracuda Ad-

vanced Composites - DIAB’s distributor in Brazil

- using a combination of carbon and aramid

fibers over a Divinycell core.

As a result the sledge is very light (less than

22 kg. [48 lb.]) yet it is extremely strong. In

recent trials carried out by Julio at Patriot Hills,

Antarctica, it was able to withstand buffeting

by 130 km (90 mph) winds.

“It tended to rock a bit, even with me inside.

However, just like a sailing boat, it rotates to

face the wind.”, reports Julio. He added, “As

a result of the excellent insulation properties

provided by the Divinycell core, it was a very

comfortable +20°C (68°F) inside, despite the

outside temperature being -15°C (5°F).

Solar panels mounted on either side of

the craft will charge any electrical/electronic

equipment.

Julio is a very experienced polar explorer

having previously undertaken nine polar ex-

peditions including two visits to both the North

and South poles.

After further trials, Julio is aiming to carry

out a 1,200 km (746 miles) solo South Pole trip

in the near future. He will haul all his gear and

supplies inside the capsule and then use it as

a snug, safe haven when resting.

www.barracudatec.com.br

ThailandTel +66 (0)38 465 388Fax +66 (0)38 465 389


Julio Fiadi and his sandwich composite sledge that was engineered by Barracuda Advanced Composites.

Diab Foam Materials

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