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Preformed Fabric Expansion Bellowsfor

Penetration Seal of HRSG

Content

1. Why is the Preformed Fabric Expansion Bellows?

2. Features of Metallic Expansion Bellows Failure

3. Causes of Metallic Expansion Bellows Failure

4. Major Causes of Metallic Expansion Bellows Failure

5. Configuration of Preformed Fabric Expansion Bellows

6. Merits of Preformed Fabric Expansion Bellows

7. Procedure of Field Splicing

8. YONGKWANG Experience

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1. Why is the Preformed Fabric Expansion Bellows?

1. The metallic expansion bellows used at pipe penetration area of HRSG casing have had continuously problems by various causes (SCC, spatter, dent, etc.) during erection and operation.

2. Leaking high temperature gas due to failures of bellows becomes the cause of hot spot around bellows or damages to the surrounding equipment.

3. Repair of metallic bellows is very special work and take long time and lots of cost. (Special welder needed)

4. This problem increase a lot of additional cost during construction, commissioning and operation.

5. Some companies tried to solve this problem with very expensive methods.(Multi Plies, Inconel Bellows)

6. We need new material & method to solve this problem.- More Flexibility- More Easy Replacement

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2. Features of Metallic Expansion Bellows FailureThe metallic expansion bellows used at pipe penetration area of HRSG casing have had continuously problems by various causes (SCC, spatter, dent, etc.) during erection and operation.

(Welding Spatter) (Welding strike Hole) (Big Dent) (Insufficient Insulation)

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3. Causes of Metallic Expansion Bellows Failure

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4. Major Causes of Metallic Expansion Bellows Failure

Major cause of failure was SCC and physical damages.Many of failure cases depended on the skill of welders or workers.

SCC (Stress Corrosion Cracking) Elements.- Tensile stress- Corrosive environment- Susceptible alloy

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5. Configuration of Preformed Fabric Expansion Bellows

1) Bellows MaterialHeat Resistant Textile (DUPONT NOMEX):

2 LayersDurable temp. : 200 ℃Flame Resistant Silicone Rubber Compound:

3 LayersDurable temp. : 200 ℃

2) Design ConditionGas temp. : Max 650℃

Insulation outside temp. : 100℃

Bellows material durable temp. : 200℃

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5. Configuration of Preformed Fabric Expansion Bellows3) Bellows Configuration

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6. Merits of Preformed Fabric Expansion Bellows

1. Stress and physical attacks can be released by rubber based silicon with high flexibility

2. Compound bellows material based on silicon with NOMEX Fabric is stable at critical environment such as heat, chemical, weather, etc.

3. Therefore major causes of bellows failure SCC, physical attack are expected to be controlled.

4. Workability for erection and repair will be better, easier alignment and fit-up

5. The special welders are not required.

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7. Procedure of Field Splicing

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8. YONGKWANG Experience

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Customer Country Location Year

Doosan Heavy Industries Co., Ltd. Oman Barka 2011

Doosan Heavy Industries Co., Ltd. Oman Sohar 2011

Doosan Heavy Industries Co., Ltd. India Dgen 2010

Doosan Heavy Industries Co., Ltd. Israel Ramat Hovav 2011

Doosan Heavy Industries Co., Ltd. Israel Hagit 2012

Doosan Heavy Industries Co., Ltd. Israel Eshikol 2012

Doosan Heavy Industries Co., Ltd. Bangladesh New Haripur 2011

Doosan Heavy Industries Co., Ltd. Saudi Arabia Ras Az Zawr 2012

Doosan Heavy Industries Co., Ltd. Korea Sejongsi 2012