«Innovative Binder and Refractory Coating Solutions For Highly Complex Castings»

«Kompleks Döküm Parçaları İçin Yeni Bağlayıcılar ve Refrakter Kaplamaları» Amine Serghini

(Metko HA)

4.Oturum: Kalıp ve Maça Teknolojileri 4th Session: Mould & Core Technologies

Oturum Başkanı/Session Chairman: Dr. Türsen Demir (Çukurova Kimya End. A.Ş.)

Oturumlarda yer alan sunumlar 15 Eylül 2014 Pazartesi tarihinde kongre web sayfasına (kongre.tudoksad.org.tr) yüklenecektir.

CHEMISCHE WERKE GMBH

7th International Ankiros Foundry Congress

September– 12th

, 2014

Innovative binder and refractory coating solutions for high complex castings

Amine Serghini* & Dr. Klaus Seeger

3

ENVIRONMENTAL REGULATIONS

IN EUROPE

1865 1906 1950 1960 1970 1980 1985 1990 1995 2006

0

200

400

600

800

Total:

800 Laws

2.800 Regulations

4.700 Administrative ruling

1865 - 1970: 20 Laws

1986 - today: >> 800

Laws / Guidelines

1971 - 1985: 94 Laws

With a growing environmental consciousness the number of environmental

laws and guidelines increased dramatically in recent years.

CO2-Emission standards for PC Worldwide

USA

CaliforniaCanada

Australia

China

EUJapan

100

120

140

160

180

200

220

240

260

280

2002 2004 2006 2008 2010 2012 2014 2016 2018

Year

CO

2-e

mis

sio

n [

g/k

m]

Light Construction using Downsizing

06A 1,6L – 2,0L

75 – 165 KW

06F 2,0L

125 – 200 KW

06H 1,8L – 2,0L

88 – 155 KW 06K 1,8L – 2,0L

125 – 221 KW

NA / Turbo

TFSI - ZKG 0

TFSI - EVOII

TFSI – Gen.3

Development of weight and Performance of engine blocks

From 1,6 – 2,0L GJL250

source: W.Görtz – Die Herstellung von hochkomplexen ZKG

Eisenwerk Brühl FST Duisburg 2014

5

Integration of different parts in the casting

• higher core complexity

Light construction

• core package production

• higher binder consumption

• thinner wall thickness

• restricted tolerance

Higher component load

• constant metallurgical proprieties

• Need for feeders

Lower costs

• Automation

Challenges by downsizing

Enhanced complexity

• 40 cores/ Flask for 4 engine blocks

• 173,6 kg core sand / Flask for 4 engine blocks

• 56 cores/ Flask for 4 engine blocks

• 333,4 kg core sand / Flask for 4 engine blocks

source: W.Görtz – Die Herstellung von hochkomplexen ZKG

Eisenwerk Brühl FST Duisburg 2014 7

3 mm

Wall thicknesses and tolerances for new

engine casting

8

6 - 8 mm

Former Casting

Wall thicknesses and tolerances for new

engine casting

9

Composition of the various Cold-Boxcomponents

0

10

20

30

40

50

60

70

80

90

100

Gasharz (Part 1) Aktivator (Part 2) Catalyst

Rate

[%

]

chemical agent main solvent co-solvent additivs

Solvent behaviour in PU-Cold-Box resin

14.09.2014 11 Präsentationsvorlage

Primarily:

• To reduce the viscosity of the base resin

Secondary

• To enhance several properties of the binder

Solvent influence:

• The gas behaviour of the binder system

• The Hazardous and fume emission of the binder

• The odour emission after pouring

Reducing the solvent content:

• Reducing the viscosity of the base resin

Viscosity of the base resin

• Modify the structure of the binder

12

Structure of various Cold-Box-Resins

OH OH

O

OH

OHOH

m

n

OH OH

O

OH

OHOH

n

m

OH OH

O

OH

O

m

n

Si

OH OH

O

OH

O

n

m

O O

OSi

OSi

O

OO

O

O

O

13

SIPURID-Structure - properties

1. Reduction of the OH-Groups Polarity reduced

Application of simple solvent packages possible

Viscosity of the base resin is reduced

Application of less solvent possible

Amount of Isocyanate can be reduced

2. Increase of the molecular mass

thermal stability improved

OH OH

O

OH

O

m

n

Si

OH OH

O

OH

O

n

m

O O

OSi

OSi

O

OO

O

O

O

Composition of the various Cold-Box

components

0

10

20

30

40

50

60

70

80

90

100

SIPURID 1 SIPURID 2 Catalyst

Co

nte

nt

[%]

chemical agent main solvent additives

Emissionen – Hazardous- BTX values

15

0

50

100

150

Benzol Toluol Xylol

SIPURID: reduce of gas pressure into the core

17

SIPURID– Practical experiences

Standard binder New binder

Section through a core package in casting position by cutout over a range of core and a

section of the corresponding cylinder block

Wall thicknesses and tolerances for new

engine casting

Due to the high complexity of these castings the number is increasing

especially in filigree thin and very complex cores. The risk of gas-related

casting defects will increase.

Wall thicknesses and tolerances for new

engine casting

For the production of complex castings in the core package technology

the use of more specific and tailored coatings to their production is

necessary.

uniform application thickness

very effective against sand expansion defects

controlled gas permeability

controlled refractoriness coated side part of a core package with integrated channel cores

Wall thicknesses and tolerances for new

engine casting

Wall thicknesses and tolerances for new

engine casting

350 to

400 µm

250 µm

Task

Formulation of suitable coating which can be applied thin and still eliminates casting

defects such as veining or penetration and offer an excellent peel-off from the casting

Testing carried out to improve cleanliness

Method:

A test casting was carefully designed to demonstrate adherence in thin

wall sections

Dipping procedure was improved to ensure constant coating thickness

Various coating formulation types were trailed

Test bars were produced, coated dried and inserted into the test

moulds ready for casting

Simulation of casting geometry

2.7 mm

22.4

mm

5.7 mm

Casting test: view of the mould

Grey Iron

Casting temp.: 1450 °C

Casting weight: 21 kg

The thin test bars simulate the customer conditions and the different

applied coatings show the performance of this

Measurement of layer thicknesses on test bars

Dip

pin

g d

irection

Test bars were measured in positions

1 – 3

Coating applied with an automatic

dip machine

Dipping time: 3 sec.

Hold time: 5 sec .

Removal : 3 sec.

Sand mixture:

100 pbw Silica sand

1.6 pbw Cold-Box binder

Layer thickness of different coatings

Coating A Coating B Coating C Coating D Coating E

Layer [µm]

Position 1 400 390 450 350 220

Layer [µm]

Position 2 490 440 510 360 220

Layer [µm]

Position 3 500 450 520 370 230

Δ Layer 1 to

Position 3 [µm] 100 60 70 20 10

3/5/3s

Observations:

Lower part of the core always has a tendency to pick up more due to the

higher pressure forces, building thickness onto the sand core

Choice of coating is important in obtaining consistent thickness on cores

Peel-off of different coatings

The above shows the sectioned casting with reduced adherences in section 9 and 10

Peel-off of different coatings

Coating A Coating E

Cleanliness

Cleanliness after casting / peel-off of the refractory coating

example: casting surface around the water jacket

Extensive sticking of the refractory

coating on the casting surface

Barely any refractory coating residues

to be found on the casting surface

(Source: Neue Halberg Guss GmbH, Brebach)

Summary

• Thin-walled engine blocks with integrated functionalities to reduce

the CO2 emission of future generations of motor vehicles

• The number of cores increases significantly and the complexity as

well

• Engine blocks are therefore produced by core package method with

vertical pouring

• New requirements for core binders and particularly for the coating

materials and their compositions:

• to cope with the task of gas evolution or gas problems

• to avoid expansion defect by low coating thickness

• to enhance the release of the coating after casting

• To guarantee a constant working condition an automatic viscosity

control has been developed

CHEMISCHE WERKE GMBH

Thank you for

your attention!