Information Technology Reference
In-Depth Information
Lathe
CNC
SPM
Interest costs
Annual amount subject
to interest (
A
)
A
=
U
$251,300
$249,600
$264,678
Interest per year
(
i
)
$17,591
$17,472
$18,527.46
i
=
A
r
Interest per part
(
I
)
I
=
i
/
D
$0.0117
$0.0116
$0.0124
Overhead costs
Annual overhead costs
(trans., rent, etc.) (
v
)
$30,000
$20,000
$15,000
Overhead cost per part (
O
)
O
=
v
/
D
$0.02
$0.0133
$0.01
Total production cost
per part
(excluding the cost
of material)
$4.7423
$0.5211
$0.2138
Table 3. Machining costs for traditional lathe, CNC, and SPM
6. Conclusions
Production quality and low production cost are essential for the success of manufacturers in
today's competitive market. SPMs are very useful for producing large quantities of high
quality products at low costs. These machines can also be altered to produce similar
components when necessary. High accuracy, uniform quality, and large production
quantities are important characteristics of SPMs. However, the inadequate knowledge of
machining specialists with this technology has resulted in its low utilization in
manufacturing firms. In this article a detailed discussion of SPMs, their capabilities and
accessories have been described. It also explained the development of a KBES to assist SPM
users in deciding whether or not to make use of SPMs for a given production task. An
analysis was made on the basis of technical and economical considerations. The case study
presented clarified the method of analysis between three methods for producing a typical
part. After a detailed discussion and extensive computations it has been concluded that for
the given production task SPM would result in a significant 59% reduction of costs when
compared to CNC, and an unbelievable 95.5% cost reduction was achieved when compared
to traditional lathe. The system described in this work significantly reduces the time and
effort needed for decision making on utilization of SPMs and determination of machine
layout. In addition, the system developed minimizes the level of expertise required to
perform the analysis and eliminates possible human errors.
The current system focuses on drilling and drilling-related operations. More work is
needed to cover other machining operations including milling. Also the KBES developed
currently works on a standalone basis. Work is in progress to integrate it with the 3D
CAD modelling system such that the information could be directly extracted from the
CAD system, eliminating the need for manual data input by user. A database of standard
