Optimization of machine downtime in the plastic manufacturing

Figures & data

Table 1. Cycle time (s) per type of plastic product

Product	Cycle (s)
Boss chair	100
View chair	90
Honour chair	90
Dine leg	45
Dine top	120

Table 2. Compute OEE (%) for boss chair at different shift periods

Shift (h)	Availability	Downtime (min)	Performance	Quality rate	OEE (%)
8	0.75	120	0.88	0.99	65
16	0.86	134	0.94	0.99	80
24	0.89	158	0.92	0.99	81
32	0.86	269	0.91	0.99	77
40	0.88	288	0.93	0.99	81
48	0.88	322	0.93	0.99	81
56	0.87	437	0.92	0.99	76
64	0.87	499	0.91	0.99	78
72	0.87	561	0.92	0.99	79

Figure 1. Illustration of the products pit stops for the first shift of 8 h.

Table 3. Increment in production time due to weekly pit-stop

Product	Pit-stop every 24 h	Production rate 24 h	Pit-stop weekly	Production rate weekly	Differences
Boss chair	5,908	251	6,030	391	140
View chair	6,580	281	6,700	401	120
Honour chair	6,580	281	6,700	401	120
Dine leg	13,160	546	13,400	786	240
Dine top	4,935	205	5,025	290	90

Table 4. Multiple regression results for 16 h

Subhead		Unstandardized coefficients		Standardized coefficients	Significance
		B	Std. error	
1	Uptime	−0.290	0.007	−3.635	0.015
	Weight	0.840	0.065	2.317	0.049
	Cycle time	0.001	0.002	0.103	0.674
	Quantity/shift	0.004	0.000	2.578	0.019

Note: R² = 1 (p < 0.05).