1. FABRICATION OF ENGINE EXHAUST DUCT FOR CYLINDER NINE TO
PROCTECT TURBO CHARGER
RESEARCH AND DEVELOPMENTPROPOSAL FOR FABRICATION OF
ENGINE EXHAUST DUCT
BY
KENYA ELECTRICITY GENERATING COMPANY LIMITED
TEAM.
JULIUS ODUMBE
IBRAIM ILIGA
JUMA NGAO.
YEAR: January, 2014
RESEARCH AND DEVELOPMENTPROPOSAL FOR FABRICATION OF
ENGINE EXHAUST DUCT
1.0 Abstract
Studies have shown the new model engines have re disgned the exhaust duct to save the
turbo charger damages as shown below.
2.0 Table of Contents
1.0 Abstract.....................................................................................................................................1
2.0 Table of Contents .....................................................................................................................2
3.0 Definitions ...............................................................................................................................3
4.0 Introduction .............................................................................................................................4
5.0 Background ..............................................................................................................................5
6.0 Overall Objectives of the project .............................................................................................6
7.0 Description of the proposed project .................. .....................................................................7
8.0 Plan of Action ...........................................................................................................................8
9.0 Estimated Budget for the Initial Experiment ............................................................................9
10.0 Project Timetable ...................................................................................................................10

2. 11.0 KenGen personnel..............................................................................................................11
12.0 Conclusion ............................................................................................................................ 12
13.0 References .............................................................................................................................13
14.0 Appendices ............................................................................................................................ 14
14.1 Comparison of original exhaust duct and newly redigsned at Kipevu.........................
........15
14.2 Photographof the original spare exhaust duct and the fabricated one in Kipevu...............
16
14.3 A typical 5 megawattmodulartotal flow turbine generatorbyLangsonEnergy ........... ......17
3.0 Definitions
1. Duct : - means the connecting pieces from one expansion bellow to another and
act as manifold for cylinder head.
2. Gases: - means exhaust leaving the combustion chamber heading to the chimmey.
3.Ccollection trap: - is a recesses curved to collect any particles from engine heading to
turbo charger turbine.
4.Aarrows Flow: - means flow of exhaust gases direction.
5. Debris:- collection of particles from engine or along the exhaust duct.
4.0 Introduction
Kipevu engines were designed with straight exhaust duct which collect the exhaust gases
from online cylinder heads to turbo charger. The gases drive the turbo charger and extract
the hot gases out to the exhaust chimmeys and the same time compressor wheel draw in fresh
air to the engine combustion chamber.
When the above operation takes and any failure of engines like valve stems shear due to
fatique stress or debris from the exhaust duct, they carried straight to the turbo charger and
hence the failures of several turbo charger rotors since the power station was commissioned.
PROPOSED SOLUTION
The designed duct is to replace the original designed on cylinder nine in a way with which
can trap the debris from the cylinders and the exhaust duct before they damage the rotor.
FUNDING
The proposed duct can be fabricated from local materials and within Kipevu facilities
assembled and installed at the cost of ksh.800.00, Or can be tendered to the moulding factory
at an approxiamately ksh.1.8million per duct.

3. EXPERTISE
The proposed exhaust duct will save the damaging of turbo charger rotary parts which the
cost of a new one is approaximately ksh.35million. The duct designed with an off cut and
near the main flange to turbo charger bellow and inclined to enable debris fall in and later
removed by opening the bottom flange.
TABLE OF CONTENTS
a. 1 pc of 260mm dia.x 12mm thickmildsteel elbow
b. Two pcs mildsteel l flangesmachinedanddrilledtosize
c. Weldingrodslowhydrogen
d. Otherpreparationtoolse.g.weldingmachine,grindingetc.
ORIGINAL DUCT
SHOWING THE FACE WHICH IS IN CONTANT CYLINDER

4. PROPOSED DESIGN

5. 10"
INCLINATION
TO
FALL
BACK
DEBRIS
COLLECTION TRAP
FLA
N
G
E
TO
A
B
U
TT
C
LY
LIN
D
E
R
DIRECTION OF FLOW
EXHAUST
GASES
DEBRIS
TURBOCHARGERBELLOW
FROMCYLINDERNO8
INTIAL FABRICATION

6. .

7. PHOTO SHOWS TRAPPING GAP AND MACHINING OF THE FLANGE FACES