Abstract:
This research is a study of engineering economics for investment in Metal parts of
T8 steel lamp. Initially, the company hired outsource company to produce all metal
parts. When assembling the lamp, the company found a lot of NG parts that could not
be assembled. It affected the assembly line, customer's orders that the company could
not deliver goods on time and lack of competition in the industry market. When
calculating the present value (PW) of the 4 metal parts of the T8 steel lamp : Body cover (PW = 7,063,165.27), Top cover (PW = 6,197,084.58), Head cover (PW = 3,589,708.31)
and Clip lock metal (PW = 972,017.14), all 4 metal parts have a PW > 0. Thus, this
project is considered to invest. The IRR rate of 4 metal parts were higher than MARR
(9%): Body cover IRR = 256.78%, Top cover IRR = 340.29%, Head cover IRR = 325.05%, and
Clip lock metal IRR = 68.37%, showing that the production of metal parts of T8 steel box are suitable for own investment. The researcher evaluated the risk by comparing
between two projects : outsource hire and own investment. In conclusion, the company decides not to hire outsource for producing products due to the uncontrollable risk. The payback period (PB) of the 4 metal parts investment are at 0.22 years or 2.5 months.