Production, Optimization and Quality Control of Fuel Injectors Manufacturing

Production, Optimization and Quality Control of Fuel Injectors Manufacturing.

MMAE-557

Personal Consulting Project

Acknowledgement

Several people should be mentioned for their contributions to the paper. I am grateful to the following: Prof. J. Cesar one of the Illinois Institute of Technology, Chicago, USA, for his thoughtful reviews of Chapters 13 to 23 in Automation Production, Systems and Computer Integrated Manufacturing Book.

Abstract

The project gives an outline for Fuel Injector production, its Manning Level estimation and quality aspects to be improved to achieve better production. Fuel Injectors are the main components of Diesel Engines. DSLA is a convential type injector. It has two main components- body and needle. In our project we discussed about the soft stage of injector body. The production line is semi automated, with raw material coming from the vendor, and the production starts with inscription rolling, where batch number is assigned to Kanban batch. Then onwards the production in every machine is done on the according to batches. Process control is done using SPC charts. And one worker is engaged for control and quality supervision of final product.

Table of Contents

Section No Description Page No

1 Client Description 5

2 Analysis of production line 13

3 Cycle time Calculations 14

4 Optimization 18

5 Automation 24

6 Quality Assurance 25

7 Results 26

8 Literature Sited

27

9 List of Figures 28

Section 1

Client Description

CLIENT: MICO BOSCH (FUEL INJECTOR MANUFACTURERS)

Soft stage of DSLA nozzle body is taken.

Low Productivity, Manning Level is high, Automation is required.

Production Line: Containing 9 stations.

Production rate required is 12000 parts/day.

Number of Workers: 9 or more

Work Schedule: 3, 8hr shifts per day, 7 days per week, 52 weeks per year.

Classification: III H, S

Process Description:

This is semi automated production line with nine station and each station operates separately. The operations done on the line are Inscription rolling, Guide bore drilling, operation on spinner, collar grinding, Inlet and dowel hole drilling, high pressure cleaning, ECM, piscal cleaning, ball turning. All the operations are independently. All the machines can have multiple machines except for ECM, because it is costly and machine takes a large place with all its storage tanks. So the ECM becomes bottleneck for the line.

Workstation 1(Inscription rolling):

Kanban production system is followed on the line, so the parts are divided in to batch of fifty number each. Every batch has batch number, which would be same for all the fifty parts in a batch. The batch number is in scripted on the part at this station. The machine consists of eccentric wheel, with numbers embossed on it.

Fig 1: Inscription Rolling

Workstation 2(Guide bore drilling)

This is done Widma Gun drilling machine. The guide bore is the hole in which the needle vibrates. The length of the drill would be around 35mm. Four parts are loaded at a time on the machine and four different gun drilling spindles drill the four parts simultaneously. The worker has to load the the parts on the holders and start the cycle, the operation is done and the parts are unloaded automatically. The machine is having high frequency of breakdown. Which makes it very critical operation.

Fig 2: Guide bore Drilling

Workstation 3 (Spinner)

This is CNC machine. The operations done on this machine are sink seat drilling, counter bore drilling, sack hole drilling, top face facing. All the operations are done sequentially, The seat is the place, where the other part of the fuel injector that is the needle rests on. The sack hole is the place a small portion where the oil is pressurized. The facing of the top face is very important as it decides the stroke of the injector. One part is done at time. Batch of fifty parts are dropped in the vibratory bowl feeder, the parts are from the feeder are passed though a fool proofed passage in to the machine. The part is hold in automatic chuck. The spindle speed varies for each operation. The finished part is dropped in to the basket underneath the machine. The worker collects the batch parts and goes to the next machine.

Fig3:Spinner

Workstation 4(Collar grinding)

The collar of the part is grounded here. The parts are grounded so that the parts are having exact fit in the machine. This is a center less grinding. The parts are passed through two grinding wheels. The parts are loaded on conveyor belt which operates by motor, the parts are passed through the wheels and is collected in the basket after the machine. This is continuous process which takes place with out any manual intervention.

Workstation 5( Inlet and Dowel hole drilling)

This is done on widma machine. The inlet hole is the one from which the compressed oil is passed in