Quick comparison
Description of comparison | C.O.D. | Conventional Method | ||
---|---|---|---|---|
Outer Duct | Inner ducts | Outer Duct | Inner ducts | |
Raw material | H.D.P.E | H.D.P.E | P.V.C. | H.D.P.E |
Length | No limit | No limit | 6 meters(At maximum) | No limit |
(Up to 500m or 1,000m) | ||||
Connection | No need (saves materials and accessories) |
In every 6 m | ||
Insertion of inner ducts | No need | To insert | ||
Intermediate Manhole | No need to build | To build in turning point | ||
Horizontal alignment of inner duct |
Straight | Straight | Straight | Straight |
Saves optic cable about 3 to 5% | ||||
Trench Dimension (Volume) (28mm inner ducts in 112mm outer duct) (Dimension) |
(No need man-working space: vertical cut) Up to 5 inner ducts 0.3m(W) x 0.6m(H) |
(Slope cut to secure man-working space) 3 inner ducts only 0.5m(W) x 0.81m(H) |
||
Trench Bedding | Rough bedding (passes over/by hurdles) |
Fine bedding |
Physical characteristics
1. Work Flow2. Trench Dimension
Physical characteristics
Physical Testing Items | Unit | HDPE | PVC | Remarks (HDPE) |
---|---|---|---|---|
Gravity | g/㎤ | 0.95 | 1.43 | Lighter |
Tensile Strength | Kg/㎠ | 260~260 | 350~600 | More strength |
Tensile Modulus | Kg/㎠ | 10,000~12,000 | 25,000~35,000 | Less Modulus |
Curvature Strength | Kg/㎠ | 350 | 860~1,000 | Easier bending |
Curvature Modulus | Kg/㎠ | 8,500 | 23,000 | Easier bending |
Impact Strength | Kg.Cm/㎠ | <13.8 | 5~6 | More strong |
Hardness | Shore-D | 64 | 70~90 | Less hard |
Specific Heat | Kg.Cm/㎠ | 0.55 | 0.24 | More resistance |
Softening Point | ℃ | 121 | 80~90 | More endurance |
Limit of usage temperaure | ℃ | From -60~60 | From -5~60 | Much less limit |
Withstand Voltage | Kv/mm, 1 minute | 48 | 28~32 | More reistance |
Cost comparison
Comparison of Economy of COD-5B vs PVC for
500 meters of COD 110mm(O.D.) with 90mm(I.D.) : 5 subducts of 28/33mm
500 meters of PVD 100mm(O.D.) with 90mm(I.D.) : 3 subducts of 28/33mm
US$1=\1,140Unit : US$
Work Description | Calculation/ Job description |
Unit | Qty man/day |
Unit Cost |
Amount | Remarks |
---|---|---|---|---|---|---|
1.Matrial: A. PVC Ducting System 1)Outer Duct 2)Inner Duct 3)Coupler |
PVC(100/90mm) HDPE tube(28/33) Or coupling material |
6m m Piece |
84 1,500 84 |
18.018 0.67 . |
1513.474 998.6842 0 |
. |
Total | 2512.158 | |||||
B. COD-5B . |
Outer Duct:90/110mm Inner Duct:28/33mm |
m . |
500 . |
6.14 . |
3070.175 . |
Readily built-in |
2. Installation A. PVC 1)PVC Laying 2)Connection of Outer Duct 3 Insertion of 5Inner Ducts 4)Cleaning of Outer Duct |
For 500m of PVC 145mm Duct & 5*42.4mm Inner Ducts. |
0.10M/D Per 6m 0.26M/D Per 6m 0.083M/D Per 6m 0.04M/D Per 6m 0.48M/D Per 100m 0.53M/D Per 100m 0.44M/D Per 100m (0.6+0.34) Per 100m |
||||
Pipe Layer General Labor Pipe Layer General Labor Pipe Layer General Labor Pipe Layer General Labor |
(500m) (500m) (500m) (500m) (2,500m) (2,500m) (2,500m) (2,500m) |
8.40 21.84 0 0 0.02 0.02 0.00 0.00 |
||||
Total | Pipe Layer General Labor Sub-total |
8.42 21.86 30.28 |
64.48 45.94 |
542.9997 1004.45 1547.447 |
Inner Duct(3+2):440% |
|
Total Conventional System | 4059.605 | |||||
Unit Cost of per linear meter of Inner Duct | 2.706 | US$/meter | ||||
B. COD (for 5 Inner ducts: 2,500n) |
Pipe Layer General Labor |
(500m) (500m) |
28.50 9.00 |
64.48 45.94 |
1837.70 413.48 |
0.018M/D Per 100m 0.057M/D Per 100m |
Sub-total | 37.50 | 2251.18 | Practically:50% applicable | |||
Total COD | 5321.35 | |||||
Unit Cost of per linear meter of Inner Duct | 2.129 | US$/meter |
Comparison of Economy of COD-5B vs PVC for
500 meters of COD 110mm(O.D.) with 90mm(I.D.) : 5 subducts of 28/33mm
500 meters of PVD 145mm(O.D.) with 135mm(I.D.) : 5 subducts of 36.4/42.4mm
US$1=\1,140Unit : US$
Work Description | Calculation/ Job description |
Unit | Qty man/day |
Unit Cost |
Amount | Remarks |
---|---|---|---|---|---|---|
1.Matrial: A. PVC Ducting System 1)Outer Duct 2)Inner Duct 3)Coupler |
PVC(135/145mm) HDPE tube(35.4/42.4) Or coupling material |
6m m Piece |
84 2,500 84 |
58.772 0.921 . |
4936.842 2302.632 0 |
Estimate only |
Total | 7239.474 | |||||
B. COD-5B . |
Outer Duct:90/110mm Inner Duct:28/33mm |
m . |
500 . |
7.35 . |
3676.21 . |
Readily built-in |
2. Installation A. PVC 1)PVC Laying 2)Connection of Outer Duct 3 Insertion of 5Inner Ducts 4)Cleaning of Outer Duct |
For 500m of PVC 145mm Duct & 5*42.4mm Inner Ducts. |
0.12M/D Per 6m 0.32M/D Per 6m 0.083M/D Per 6m 0.04M/D Per 6m 0.48M/D Per 100m 0.53M/D Per 100m 0.44M/D Per 100m (0.6+0.34) Per 100m |
||||
Pipe Layer General Labor Pipe Layer General Labor Pipe Layer General Labor Pipe Layer General Labor |
(500m) (500m) (500m) (500m) (2,500m) (2,500m) (2,500m) (2,500m) |
10.08 26.88 0 0 0.021 0.023 0.00 0.00 |
||||
Total | Pipe Layer General Labor Sub-total |
10.10 26.90 37.00 |
64.48 45.94 |
651.3273 1236.00 1887.322 |
Inner Duct(3+2):440% |
|
Total Conventional System | 9126.796 | |||||
Unit Cost of per linear meter of Inner Duct | 3.651 | US$/meter | ||||
B. COD (for 5 Inner ducts: 2,500n) |
Pipe Layer General Labor |
(500m) (500m) |
28.50 9.00 |
64.48 45.94 |
1837.70 413.48 |
0.018M/D Per 100m 0.057M/D Per 100m |
Sub-total | 37.50 | 2251.18 | Practically:50% applicable | |||
Total COD | 5927.39 | Material+Installation | ||||
Unit Cost of per linear meter of Inner Duct | 2.371 | US$/meter |
Quick comparison
Description of comparison | C.O.D. | Conventional Method | ||
---|---|---|---|---|
Outer Duct | Inner ducts | Outer Duct | Inner ducts | |
Raw material | H.D.P.E | H.D.P.E | P.V.C. | H.D.P.E |
Length | No limit | No limit | 6 meters(At maximum) | No limit |
(Up to 500m or 1,000m) | ||||
Connection | No need (saves materials and accessories) |
In every 6 m | ||
Insertion of inner ducts | No need | To insert | ||
Intermediate Manhole | No need to build | To build in turning point | ||
Horizontal alignment of inner duct |
Straight | Straight | Straight | Straight |
Saves optic cable about 3 to 5% | ||||
Trench Dimension (Volume) (28mm inner ducts in 112mm outer duct) (Dimension) |
(No need man-working space: vertical cut) Up to 5 inner ducts 0.3m(W) x 0.6m(H) |
(Slope cut to secure man-working space) 3 inner ducts only 0.5m(W) x 0.81m(H) |
||
Trench Bedding | Rough bedding (passes over/by hurdles) |
Fine bedding |
General Comparison
Category | Conventional P.V.C. Duct | C.O.D. (Corrugated Optic Duct) |
---|---|---|
Material & Strength |
- PVC: vulnerable to impaction damage - Disconnection: Possibility of dis-connection of connected points of outer duct due to ground compressive load. - Thermal expansion & contraction during the installation period and in service |
- Stand good against impaction damage and no damage risk from freezing temperature. - Strong Concavo-convex shape provides good strength and stays same shape against ground compressive load. - Stays stable from thermal expansion & contraction of duct during or after installation |
Installation |
- Many individual connections: maximum length is 6 meters. - To construct manhole to diverse direction of the line. - Complicated installation work as the insertion of inner ducts is in the second stage after the installation of outer duct. - Causes traffic troubles (jamming) in case of urban installation. - Inner duct may twist in the course of insertion. - Maximum number of inner duct is limited to 3 ducts. |
- No duct connections in-between two manholes up to 500 meters or more. - Single installation process: No need to go through complicated inner duct insertion process owing to readily built-in both outer and inner ducts. - To by-pass minor hurdles and skips un-necessary construction of manhole to diverse direction of line within the radiation of curbing angle. - Increase of duct efficiency by increase of numbers of inner ducts to be inserted up to 5 ducts at approx. same price. - Light weight allows easy handling and transportation. |
Economy | - High construction cost. | - Economic construction cost and time saving |