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Technical Articles
Simple Sheeter ROI
Assumptions:
| Sheets per shift 50,000 |
Roll diameter 72-inches |
| Average sheet length 40-inches |
Lineal feet per roll 15,700 ft |
| Lineal feet per Shift 166,666 |
Roll change time 15 minutes |
| Caliper 21 pt or 0.021-inches |
Skid change time 5 minutes |
| Sheets per skid 55/0.021=2,619 |
|
Labor Savings with dual position rollstand
| Production per shift (lineal ft): |
|
166,666 |
|
| Lineal per roll (72” dia and 21 pt) |
|
15,700 |
|
| Number of roll changes per shift |
|
10.6 |
|
| Time to change rolls (hrs) |
|
15/60 |
|
| Number of shifts per day |
|
3 |
|
| Production days per year |
|
246 |
|
| Total roll change time per year (hrs) |
|
1955 |
|
| Dollar cost to operate Sheeter per hour |
|
$45 |
|
| Labor savings due to quick roll change |
= |
|
$88,000 |
| Percent increase in production (1955/5904) |
= |
%33 |
|
Labor savings with continuous skid delivery
| Production per shift (sheets): |
|
50,000 |
|
| Sheets per skid (55” ht and 21 pt) |
/ |
2,619 |
|
| Number of skid changes per shift |
= |
19 |
|
| Time to do skid change (hrs) |
X |
5/60 |
|
| Number of shifts per day |
X |
3 |
|
| Production days per year |
X |
246 |
|
| Total roll change time per year (hrs) |
= |
1168 |
|
| Dollar cost to operate Sheeter per hour |
X |
$45 |
|
| Labor saving due to non-stop skid delivery |
= |
|
$52,582 |
| Percent increase in production (1168/5904) |
= |
19% |
|
Savings due to reduction in trip or jams on press with improved decurling
(Assumes 3 trips per shifts will be eliminated with improve decurling)
| Number of trips reduced per shift |
|
3 |
|
| Time down per trip on press (hrs) |
X |
15/60 |
|
| Number of shifts per day |
X |
3 |
|
| Production days per year |
X |
246 |
|
| Total time down caused by trips |
= |
553.50 |
|
| Dollar cost to operate press per hour |
X |
$120 |
|
| Savings per year due to reduction in trips on press |
= |
|
$66,420 |
| Number of sheets wasted per trip |
|
20 |
|
| Number of trips reduced per shift |
X |
3 |
|
| Number of shifts per day |
X |
3 |
|
| Production days per year |
X |
246 |
|
| Total sheets wasted per year |
= |
44,280 |
|
| Average sheet size (ft2) |
X |
5.2 (25” x 30”) |
|
| Ft2 of wasted board per year |
= |
230,625 |
|
| Actual cost of board per ft2 (70 lbs/1000 ft2) |
X |
$0.0175 |
|
| Savings due to waste reduction |
= |
|
$4,036 |
| |
+ |
|
$66,420 |
| Total savings due to reduction in trips |
= |
|
$70,456 |
Summary of Savings in first year:
| 1. Rollstand and Splicer savings |
$88,000.00 |
| 2. Continuous Skid Delivery savings |
$52,582.00 |
| 3. Total saving due to reduced trips |
$70,456.00 |
Total Savings with Upgrades |
$211,083.00 |
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