Application Guideline for the Bellows{1061} Caterpillar

On-highway Engines:

C11 (S/N: KCA1-UP)

C13 (S/N: KCB1-UP)

C15 (S/N: BXS1-UP; MXS1-UP)

Introduction

This Special Instruction will address the following applications for the bellows: the installation, the handling and the reusability. The bellows that will be discussed are used on engines with turbochargers in a series.

Installation

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The ends of the bellows are very sharp. Injury could occur if the bellows are not handled properly. Handle the bellows by the convolutions.

The bellows that is on the exhaust side of turbocharger will include a inner liner. The liner will help shield the convolutions from damage. The damage is mainly caused by heat. Bellows on the air side of the turbocharger do not require a liner. The part numbers are different for the bellows with an inner liner and the bellows without a liner.

Illustration 1	g01121141
Typical example that shows the correct lateral alignment

The alignment of the bellows is important. Improper lateral alignment is two sealing surfaces that do not align with each other. The proper lateral adjustment is shown in illustration 1.

(1) Center of the bellows between the two compressors

(2) End of the high pressure compressor

(3) Bellows

(4) End of the air duct

Proper alignment means that end (2) and end (4) are in alignment with each other by visually checking centerline (1). Do not force the bellows into the position. End (1) or end (4) should not be forced into bellows (3) .

Note: Make sure that you loosely fit all of the parts before the final torquing is started.

Illustration 2	g01018530
Typical example

(5) Bellows on the exhaust side

Reusability ... 10 assembly cycles

Axial tolerance ... ±2.84 mm (±0.120 inch)

Lateral tolerance ... ±1.68 mm (±0.066 inch)

(3) Bellows between the compressors

Reusability ... 10 assembly cycles

Axial tolerance ... ±2.79 mm (±0.110 inch)

Lateral tolerance ... ±1.96 mm (±0.077 inch)

(6) Bellows between the compressor and the precooler

Reusability ... 10 assembly cycles

Axial tolerance ... ±4.06 mm (±0.160 inch)

Lateral tolerance ... ±1.50 mm (±0.059 inch)

Illustration 3	g01016663
The View is looking down the bellows.

Illustration 4	g01023261
Example of lateral misalignment

Lateral misalignment is shown Illustration 3 and Illustration 4. Lateral misalignment on the exhaust bellows can lead to contact between liner (7) and convolutions (8). The misalignment can cause premature failure.

Illustration 5	g01016672
Example of uneven spacing with the convolutions

Lateral misalignment is identified by visually inspecting the convolutions on the bellows. The visual inspection will help ensure an even amount of spacing between each of the convolutions. Incorrect spacing between each of the convolutions is shown in Illustration 5.

Illustration 6	g01016673
Example of premature failure due to lateral misalignment

Improper alignment during installation can lead to premature failure of the bellows. An Example of premature failure is shown in Illustration 6.

Handling

Bellows should be handled by the convolutions. The convolutions are the ribbed portion of the bellows. The ends of the bellows are sharp and the ends should be handled carefully. The bellows can be damaged if the bellows are dropped. All dents may not adequately be repaired. Refer to ""reusability" " for inspection of the bellows.

Reusability

Note: If there is any indications of separation of the layers or difficulty with the installation, discard the bellows. Failure to replace the bellows could result in the following problems: improper seating, subsequent air leakage and Exhaust leakage.

The bellows consist of multiple layers of material that are pressed together.

Illustration 7	g01016669
Example of damage to the convolutions

Inspect the bellows for damage. The part should be discarded if damage to the convolutions is present. Illustration 7 shows that damage to the convolutions.

Illustration 8	g01016670
Example of a bad edge

You may attempt to repair minor damage to the ends of the bellows by using pliers. Illustration 8 shows a failed attempt to repair the edge of the bellows.