Contents
1. What a PE Corrugated Pipe Extrusion Line Is and Who Buys One
Two extruders feeding a single corrugator
A PE corrugated pipe extrusion line pairs two single screw extruders with one co-extrusion die and one corrugator, so that a smooth inner wall and a ribbed outer wall are formed together and welded into one double wall tube. The inner extruder lays down the liner that the cable will slide against, the outer extruder fills the mold blocks that create the ring profile, and the corrugator decides the pitch, the wall thickness and the production speed.
Three buyer profiles and what each one needs
A telecom contractor or a cable installation company often buys a line to secure duct supply for its own fiber projects, and that buyer cares about coil length, delivery reliability and a duct that pulls cable without abrasion. A pipe converter serving several carriers buys on cost per meter and on the ability to change diameter quickly, because a single tender may call for 40, 63 and 110 millimeter duct in the same month.
An infrastructure supplier that already extrudes solid wall conduit or water pipe is the third profile, adding a corrugated line to reach the telecommunications and drainage markets with one machine. That buyer already owns resin handling, a laboratory and a truck fleet, so the incremental project is smaller than it looks and the payback is usually the fastest of the three.
Why a double wall duct displaces solid wall conduit
A double wall corrugated duct delivers the same ring stiffness as a solid wall pipe at 35 to 55 percent of the weight, because the ribbed outer wall puts material where it resists bending and leaves the inner wall thin and smooth. Lower weight means longer coils, fewer joints per kilometer and a smaller carbon footprint per meter, and it also means the duct can deform slightly under settlement without cracking.
Polyethylene adds flexibility that polyvinyl chloride cannot match, since a PE duct survives a ground movement or a frost heave that would crack a rigid conduit, and it keeps impact strength at minus 20 degrees C. The trade is a lower stiffness per millimeter of wall and a need for proper bedding, which is why the ring class and the installation depth must be decided before the wall profile is fixed.
2. Telecom Duct Requirements That Shape the Line
The diameter range that sets the line
Telecommunication duct is sold in a small family of outside diameters, and 32, 40, 50, 63, 75, 90 and 110 millimeters cover almost every fiber and copper route from a building entry to a trunk duct bank. Diameters up to 63 millimeters are normally coiled in lengths of 200 to 500 meters, while 75 and 110 millimeter duct ships as 6 meter straight lengths or as large coils wound on a heavy frame.
Ring stiffness and impact requirements
Buried duct is specified by ring stiffness rather than by wall thickness, and the common classes are SN4 at 4 kilonewtons per square meter and SN8 at 8 kilonewtons per square meter of pipe surface. A duct under a sidewalk at 0.8 meter of cover usually needs SN4, while the same duct under a roadway at 1.2 meters with traffic loading needs SN8 or a concrete surround.
Impact is the second gate, because a coil that is dropped from a truck in winter must not shatter, and a falling weight test at minus 20 degrees C is the usual release check. A duct that passes ring stiffness but fails impact almost always has too high a melt flow index or too little comonomer, and no amount of corrugator tuning will correct a resin that is fundamentally brittle.
Inner wall smoothness and cable pulling
The inner liner determines how hard the cable is to install, and a smooth PE surface with a friction coefficient near 0.2 to 0.35 lets a puller move a fiber bundle several hundred meters without exceeding its tension limit. A liner with die lines, gels or a wavy surface raises that friction sharply, and the installation crew discovers it only when the cable stops moving halfway through a 500 meter pull.
3. HDPE Resin Grades and Raw Material Cost
Grades for a duct that must last fifty years
A pipe grade high density polyethylene with a density of 0.945 to 0.960 grams per cubic centimeter and a melt flow index of 0.3 to 1.0 grams per 10 minutes is the normal choice, because a low melt index gives the molecular weight that resists slow crack growth. A higher flow grade runs faster on the corrugator but fails a long term pressure or environmental stress test far sooner, which matters when the duct is expected to serve for fifty years underground.
A bimodal grade with a broad molecular weight distribution holds both stiffness and slow crack resistance, and it costs 40 to 110 US dollars per metric ton more than a standard grade. That premium is small against the cost of a field failure, and it also lets the outer wall run thinner at the same ring class, which recovers most of the difference in material.
Recycled content and regrind limits
Post industrial clean regrind at 10 to 25 percent is workable in the outer wall of a drainage duct, but telecommunication duct is usually specified as virgin material because the buyer cannot accept a variance in slow crack resistance over a fifty year life. A plant that wants to use regrind should confine it to the outer layer, keep the inner liner fully virgin, and prove the ring stiffness and impact results batch by batch.
Material cost per meter
A 110 millimeter SN8 duct weighs roughly 0.75 to 1.00 kilogram per meter, so at a resin price of 1,050 to 1,300 US dollars per metric ton the material in one meter costs 0.79 to 1.30 US dollars. A 63 millimeter SN4 duct weighs 0.28 to 0.38 kilogram per meter and carries 0.29 to 0.49 US dollars of resin, which is why the small diameters are sold on volume and the large ones on stiffness.
4. Complete Line Architecture and Equipment Price List
The sixteen item equipment list
The table below gives realistic budget ranges for a line producing 32 to 110 millimeter telecommunication duct at 250 to 450 kilograms per hour. All figures are in US dollars and exclude civil works, the overhead crane and the first stock of resin.
| Equipment item | Main function on the line | Typical price in US dollars |
|---|---|---|
| Inner wall single screw extruder, 65 millimeter | Produces the smooth liner that the cable slides on | 45,000 to 95,000 |
| Outer wall single screw extruder, 75 millimeter | Feeds the ribbed wall at 1.8 to 2.2 times liner output | 65,000 to 130,000 |
| Co-extrusion die with two flow channels | Joins both melts into one concentric tube before the mold | 28,000 to 68,000 |
| Corrugator with mold blocks and vacuum chamber | Forms the rib profile and sets the production speed | 180,000 to 380,000 |
| Spare mold block sets for three diameters | Allows a diameter change without stopping the plant | 45,000 to 120,000 |
| Vacuum pump set and internal air unit | Pulls the outer wall into the block and holds the liner round | 14,000 to 32,000 |
| Spray cooling tank and water circuit | Removes the remaining heat after the mold blocks | 22,000 to 48,000 |
| Caterpillar haul off with servo drive | Pulls the tube at constant speed without marking the rib | 26,000 to 58,000 |
| Planetary cutting unit | Cuts a square end while the tube keeps moving | 32,000 to 72,000 |
| Twin station coiler for small diameters | Winds 200 to 500 meter coils without ovalizing the tube | 38,000 to 85,000 |
| Straight length stacking table | Collects six meter duct for the 75 and 110 millimeter sizes | 15,000 to 35,000 |
| Chiller and temperature control unit | Holds mold block and tank water within 1 degree C | 18,000 to 42,000 |
| Granulator for startup scrap | Returns clean startup tube to the outer extruder | 11,000 to 28,000 |
| Color masterbatch dosing unit | Meters 2 to 4 percent of the orange or gray color | 4,200 to 11,000 |
| Online diameter and wall thickness gauge | Corrects the liner and wall before the coil is wound | 22,000 to 55,000 |
| Control system with recipe storage | Repeats a proven diameter setting and logs each batch | 18,000 to 42,000 |
Reading the midpoint total against a project budget
Adding the midpoints of these sixteen items gives roughly 0.94 million US dollars, and a realistic project then adds 80,000 to 200,000 US dollars for installation, commissioning, operator training and initial spare parts, plus 60,000 to 150,000 US dollars for a first stock of resin and masterbatch. Wanplas supplies one consolidated schedule so that the extruders, the corrugator, the coiler and the working capital appear on the same timeline, which is the document most lenders ask to see before releasing funds.
Capacity tiers and the items a quote leaves out
A compact line for 32 to 63 millimeter duct at 120 to 250 kilograms per hour costs 0.45 to 0.75 million US dollars and suits a converter serving one carrier, while a line for 160 to 315 millimeter duct at 600 to 1,200 kilograms per hour reaches 1.10 to 2.20 million US dollars. Quotations frequently omit the overhead crane, the cooling tower, an air compressor, a small test laboratory and a second set of mold blocks, which together add 0.15 to 0.40 million US dollars.
5. Twin Extruders, Co-extrusion Die and Layer Ratio
Inner and outer extruder sizing
The inner extruder is deliberately smaller than the outer one, because the liner is 30 to 40 percent of the wall weight and it must run at a lower output to stay smooth. A 65 millimeter barrel with a length to diameter ratio of 30 handles 80 to 150 kilograms per hour of liner, while a 75 millimeter barrel at the same ratio delivers 150 to 300 kilograms per hour for the ribbed wall.
The co-extrusion die and layer ratio
The die carries two concentric flow channels that merge just before the exit, so that the liner and the outer wall are still separate melts at the moment they meet the first mold block. A layer ratio of 35 to 65 is typical, with the liner at 35 percent of wall weight for a standard duct and up to 45 percent when the specification calls for a thicker liner to resist cable abrasion.
Matching melt pressure and temperature
Both melts should arrive at the die within 10 degrees C of each other and within 30 bar of each other in pressure, or the interface between them becomes a weak line that opens in a flattening test. High density polyethylene runs at 195 to 215 degrees C on this line, and anything above 225 degrees C begins to oxidize the surface and produces the smell that a buyer notices as soon as the coil is opened.
6. Corrugator, Mold Blocks and Vacuum Forming
How the mold blocks form the rib
The corrugator carries two continuous chains of matched mold blocks, and each pair closes around the tube to form one corrugation before opening again at the end of the cooling run. The blocks travel at the same speed as the extrudate, so the rib is formed without stretching the melt, and the number of block pairs multiplied by the pitch gives the cooling length that limits line speed.
Vacuum, air pressure and cooling length
Vacuum of minus 0.04 to minus 0.08 megapascals pulls the outer wall into the block cavity, while internal air at 0.05 to 0.15 megapascals holds the liner round against that pull. If the vacuum is too weak the rib stays shallow and the ring stiffness falls, and if the internal air is too high the liner balloons and the wall thins at the crest of each corrugation.
Cooling length is the limit on output, because a 110 millimeter duct needs 1.5 to 2.5 meters of cooled blocks before the rib is stiff enough to leave the mold without deforming. That is why line speed for large duct sits at 4 to 7 meters per minute while a 50 millimeter duct runs at 8 to 14 meters per minute on the same corrugator.
Diameter changeover
A diameter change means new blocks, a new die and a new sizing setup, and the work takes two to four hours with two people and a block trolley. The cost of that stop is 300 to 900 US dollars in lost output plus the startup scrap, so a plant selling several diameters should schedule changes in campaigns rather than on demand.
7. Cooling, Haul Off, Cutting and Coiling
Cooling tank and water temperature
A spray cooling tank of 3 to 6 meters follows the corrugator, and it removes the heat that the mold blocks could not take out before the tube left the last block pair. Water at 12 to 18 degrees C is sprayed from rings around the tube, and the outlet temperature should stay below 35 degrees C so that the coil is wound at a temperature where the rib will not flatten under its own weight.
Haul off and cutting
Two caterpillar belts pull the tube at a speed that must track the corrugator within 0.5 percent, because any slip shows as a stretched rib or a liner that separates from the outer wall. Belt pressure is set just high enough to grip the rib crest without crushing it, and a pressure gauge on each belt is the simplest way to catch a drift before it becomes a rejected coil.
A planetary cutter travels with the tube and rotates a blade around it, which gives a square end and a length tolerance of plus or minus 5 millimeters at full line speed. A stationary saw cannot hold that tolerance on a moving tube, and the rework it creates costs 0.15 to 0.35 US dollars per length in labor and lost material.
Coiling small diameters
A twin station coiler winds 200 to 500 meter coils of 32 to 63 millimeter duct on a frame 1.2 to 2.0 meters in diameter, and the tension must stay between 50 and 150 newtons to build a coil that unwinds without tangling. Too much tension ovalizes the tube and raises the pulling force on site, while too little produces a loose coil that collapses in the truck.
8. Sixteen Process Parameters and the Cost of Deviation
Sixteen settings that decide a good coil
The table below lists the settings that a corrugated duct line must control and the practical cost of running outside them. The values assume a 110 millimeter SN8 duct at 0.85 kilogram per meter running at 5 meters per minute.
| Parameter | Target value | What deviation costs |
|---|---|---|
| Liner melt temperature | 195 to 210 degrees C | Below 190 C leaves unmelted particles and die lines |
| Outer wall melt temperature | 195 to 215 degrees C | Above 225 C oxidizes the surface and creates odor |
| Die body temperature | 200 to 220 degrees C | A gap above 10 C between layers weakens the interface |
| Die pressure | 150 to 300 bar | Below 120 bar leaves the rib crest unfilled |
| Liner share of wall weight | 30 to 40 percent | Below 25 percent cuts ring stiffness by 8 to 12 percent |
| Mold vacuum | Minus 0.04 to minus 0.08 megapascals | A weak vacuum rounds the crest and loses stiffness |
| Internal air pressure | 0.05 to 0.15 megapascals | Above 0.20 megapascals balloons the liner and thins it |
| Mold block temperature | 15 to 25 degrees C | Above 35 C distorts the rib as the blocks open |
| Cooling water temperature | 12 to 18 degrees C | Above 25 C forces a 15 percent cut in line speed |
| Line speed | 4 to 7 meters per minute | Above 8 meters per minute stretches the crest thin |
| Haul off tension | 200 to 800 newtons | Excess tension pushes ovality above 2 percent |
| Corrugation pitch | 20 to 40 millimeters | A 1 millimeter pitch error moves stiffness by 5 percent |
| Liner thickness | 1.0 to 2.0 millimeters | A liner 0.2 millimeters thin raises pulling friction |
| Outer wall thickness | 0.8 to 1.5 millimeters | 0.1 millimeter thin drops ring stiffness by 6 to 9 percent |
| Cut length tolerance | Plus or minus 5 millimeters | Outside that band needs a second trim at 0.15 US dollars per length |
| Coiler tension | 50 to 150 newtons | High tension flattens the coil, low tension makes it collapse |
The cost of drifting outside the window
A single setting outside its band rarely ruins a coil, but a drifting vacuum combined with a rising block temperature produces a duct whose ring stiffness falls just below the class limit on the third day of a run. That failure is expensive because the whole coil is rejected rather than the affected meters, and at 0.95 US dollars per meter a 500 meter coil represents 475 US dollars of cost plus the freight both ways.
Recipe discipline across diameters
Each diameter and ring class needs its own stored recipe covering melt temperature, vacuum, air pressure, block temperature and line speed, because a setting that makes a good 63 millimeter SN4 duct will produce a soft rib on a 110 millimeter SN8. Automatic recipe download prevents the operator from dialing in a new size from memory, which is the single most common cause of a bad first coil after a changeover.
9. Ring Stiffness and How the Wall Profile Delivers It
The stiffness equation in plain terms
Ring stiffness is the material modulus multiplied by the second moment of area of the wall profile and divided by the cube of the diameter, so the diameter term dominates everything else. Doubling the diameter cuts stiffness by a factor of eight at the same wall, which is why a 110 millimeter duct needs a much deeper rib than a 50 millimeter duct to reach the same class.
Profile geometry that earns SN8
The three levers on the profile are rib height, pitch and outer wall thickness, and moving from SN4 to SN8 typically needs 30 to 40 percent more outer wall thickness or a 15 to 20 percent deeper rib at a shorter pitch. A deeper rib at the same pitch adds material without much extra stiffness once the rib passes a certain aspect ratio, so the efficient route is usually a shorter pitch combined with a modest thickness increase.
Burial depth and installation class
Duct under a footpath at 0.8 meter of cover normally calls for SN4, while the same duct under a roadway at 1.2 meters with traffic loading calls for SN8 or a concrete surround. The soil type matters as much as the depth, because a well compacted granular bedding shares load with the pipe and a soft clay trench does not.
A duct that is over specified wastes money on every meter, and one that is under specified fails at the first heavy vehicle, so the class should be fixed from the route survey rather than from a default. Wanplas asks for the burial depth, the soil type and the traffic category before recommending a profile, and those three answers usually settle the class in one conversation.
10. Quality Control and Testing Cost
The tests a telecom duct must pass
A buried duct is a structural product, so the release tests are stiffness, impact and geometry rather than appearance alone. The table below lists the checks that a serious plant runs and the realistic cost of each, in US dollars.
| Check | Frequency | Typical cost in US dollars |
|---|---|---|
| Ring stiffness at 3 percent deflection | Every batch | 180 to 450 |
| Flattening test to 40 percent of diameter | Every batch | 90 to 220 |
| Falling weight impact at minus 20 degrees C | Weekly | 150 to 380 |
| Oven test at 150 degrees C for one hour | Weekly | 120 to 300 |
| Longitudinal reversion after heating | Monthly | 80 to 200 |
| Density on incoming resin | Every delivery | 60 to 150 |
| Melt flow index on incoming resin | Every delivery | 85 to 220 |
| Carbon black content and dispersion | Quarterly | 220 to 560 |
| Outside diameter and ovality | Every two hours | 10 to 30 |
| Liner and outer wall thickness | Hourly | 8 to 25 |
| Liner surface roughness | Every batch | 40 to 110 |
| Coil length and coil diameter | Every coil | 5 to 15 |
| Socket seal pressure test | Every batch | 90 to 240 |
| Laboratory instruments and fixtures | One time setup | 35,000 to 90,000 total |
In process checks and the cost of a laboratory
The two checks that catch most problems are liner thickness and ovality, and both can be done at the line in under three minutes with an ultrasonic gauge and a pair of calipers. A full laboratory at 35,000 to 90,000 US dollars adds a ring stiffness frame, a falling weight rig, an oven and a melt flow instrument, and it pays for itself the first time a carrier audits the plant and asks for three years of batch data.
Batch records and traceability
A carrier buying duct for a fifty year asset will ask for the resin lot, the melt flow index, the ring stiffness result and the line settings behind every coil, and a plant without that record cannot bid on the framework contract. Logging the coil number, the meter count and the test result against the recipe costs nothing once the control system stores it, and it turns a field complaint into a five minute lookup instead of a renegotiation.
11. Socketing, Joints and Coil Handling
Socket forming and the rubber seal
A socket is formed either inline by a heated expanding head or offline on a separate machine, and the socket depth runs 40 to 80 millimeters depending on the diameter. A rubber ring seated in a groove inside the socket compresses 25 to 35 percent when the spigot enters, and that compression is what keeps ground water out of a duct that may sit below the water table.
Joint strength and coupler choice
A socketed joint should carry at least 80 percent of the pipe wall strength in tension, because the duct is often pulled into place rather than laid, and a joint that separates mid pull costs a full re-excavation. For diameters above 75 millimeters some contractors prefer a separate coupler with two seals, which is slower to install but far more tolerant of a misaligned trench.
Coil handling and storage
A 500 meter coil of 63 millimeter duct weighs about 180 kilograms, so it can be moved with a small forklift or a coil trailer, and it should be stored flat rather than stood on edge. Ultraviolet exposure degrades an unstabilized surface within a season, which is why the carbon black loading matters and why outdoor storage should be limited to a few months.
12. Output, Energy and Labor
Building the output number
Output equals line speed multiplied by 60 and divided by the weight per meter, so a 110 millimeter duct at 5 meters per minute and 0.85 kilogram per meter produces 255 kilograms an hour. Over 6,000 productive hours at 85 percent effectiveness that is roughly 1,300 metric tons, or 1,530 kilometers of duct, from one line.
Energy per metric ton
Extrusion of high density polyethylene consumes 0.35 to 0.55 kilowatt hours per kilogram including the corrugator drives, the vacuum pumps, the chiller and the haul off, so a metric ton of duct carries 350 to 550 kilowatt hours and 32 to 50 US dollars of electricity. A line that runs the chiller at a fixed set point all year spends 8 to 14 percent more than one that tracks the wet bulb temperature.
Overall equipment effectiveness
A well run corrugated line holds 82 to 88 percent effectiveness, with the loss split between diameter changeover, startup scrap and unplanned stops on the vacuum or block chain. Raising effectiveness from 80 to 88 percent on a 1,300 metric ton line is worth 120,000 to 180,000 US dollars a year in contribution, which is more than the annual spare parts budget by a wide margin.
13. Cost per Meter and Market Price Benchmarks
Building the cost per meter
The table below builds a full cost for a 110 millimeter SN8 duct at 0.85 kilogram per meter on a single line running 1,500 kilometers a year, with all figures in US dollars per meter. It separates cash cost from depreciation so a buyer can see which lines respond to better operation and which are fixed by the investment.
| Cost element | Basis | US dollars per meter |
|---|---|---|
| HDPE resin | 0.85 kilogram at 1,050 to 1,300 per metric ton | 0.89 to 1.11 |
| Color and carbon black | 2 to 4 percent masterbatch loading | 0.02 to 0.05 |
| Electricity | 0.38 kilowatt hours at 0.08 to 0.10 | 0.03 to 0.04 |
| Direct labor | Two to three people per shift | 0.03 to 0.06 |
| Line and block depreciation | 0.94 million over five years | 0.10 to 0.16 |
| Block maintenance and spares | Annual allowance per line | 0.02 to 0.05 |
| Building and utility depreciation | 350,000 over ten years | 0.02 to 0.04 |
| Scrap handling and regrind | 4 to 7 percent of output | 0.04 to 0.09 |
| Quality and laboratory program | Annual testing and calibration | 0.01 to 0.03 |
| Packaging, coiling and end caps | Per coil delivered | 0.03 to 0.07 |
| Freight and handling allowance | Delivered basis to site | 0.05 to 0.12 |
| Total cost before margin | Sum of the eleven lines above | 1.20 to 1.80 |
The three levers that move the number
Resin accounts for 72 to 78 percent of the total, so a 100 US dollar per metric ton move in polyethylene shifts the meter cost by 0.085 US dollars, which is larger than every other saving combined. Utilization is the second lever, because the depreciation line doubles when a line drops from 1,500 kilometers a year to 750, and scrap is the third, since 7 percent instead of 4 percent adds 0.02 to 0.04 US dollars to every meter.
Market price and where a plant sits
A 110 millimeter SN8 telecom duct sells for 1.60 to 3.20 US dollars per meter depending on the market, the color requirement and whether a socket is included, and a duct made with a thinner SN4 profile sells at the lower half of that range. A plant landing at 1.20 to 1.45 US dollars of cost against a 2.20 US dollar selling price carries a gross margin near 40 percent, which is healthy for this product but only when the line stays above 70 percent utilization.
14. Investment, Payback and Wanplas Equipment Recommendations
Three configurations and their payback
An entry configuration pairs a 65 and a 75 millimeter extruder with a short corrugator and a coiler for 32 to 63 millimeter duct, reaching 800 to 1,200 kilometers a year for 0.60 to 0.95 million US dollars of funded project. A standard configuration at 0.94 million US dollars of equipment and 1.10 to 1.40 million funded covers 32 to 110 millimeters at 1,500 kilometers a year and repays in 2.2 to 3.4 years, while a large line for 160 to 315 millimeter duct at 1.35 to 2.60 million reaches 2,500 to 4,000 kilometers and repays in 2.0 to 3.0 years when half of its output is contracted before shipment.
What Wanplas supplies and how to specify it
Wanplas supplies both extruders, the co-extrusion die, the corrugator with a first set of blocks, the cooling tank, the haul off, the cutter, the coiler and the controls as one line, with a trial run on the buyer’s own resin before shipment and a written acceptance at 85 to 100 percent of rated output over four continuous hours. The scope also covers layout and utility drawings, installation and commissioning, operator and maintenance training, remote diagnostics and a recommended spare parts list, and a spares budget of 18,000 to 42,000 US dollars a year keeps unplanned downtime below 4 percent.
Frequently Asked Questions
What does a complete PE corrugated duct line cost?
A line covering 32 to 110 millimeter duct at 250 to 450 kilograms per hour costs 0.94 million US dollars for the equipment, including both extruders, the die, the corrugator, one set of blocks, the coiler and the controls. A funded project with installation, a spare block set, resin and working capital runs 1.10 to 1.40 million US dollars.
What ring stiffness does telecom duct need?
SN4 at 4 kilonewtons per square meter suits duct under a footpath at 0.8 meter of cover, while SN8 at 8 kilonewtons per square meter is normal under a roadway at 1.2 meters with traffic loading. Both classes are met by changing the rib profile rather than the liner thickness.
Can one line make both telecom duct and drainage pipe?
Yes, because the machine does not know what the duct will carry, and a drainage profile is simply a larger diameter with a different ring class. The practical constraint is block sets, since each diameter needs its own, and a plant running four sizes needs four sets at 15,000 to 40,000 US dollars each.
Why does my duct fail the falling weight test?
A failure at minus 20 degrees C almost always points to a resin with too high a melt flow index, too little comonomer or an excessive regrind share in the outer wall. Raising the melt index headroom and keeping the outer layer fully virgin usually restores impact without touching the corrugator settings.
How long can a coil be?
Coils of 200 to 500 meters are normal for 32 to 63 millimeter duct, and the upper limit is set by coil weight and by the towing equipment on site rather than by the machine. A 500 meter coil of 63 millimeter duct weighs about 180 kilograms, which one small forklift can handle.
Is recycled resin acceptable in telecom duct?
Telecommunication duct is usually specified as virgin material because the buyer must rely on slow crack resistance for fifty years, and a regrind share makes that property hard to guarantee. Clean post industrial regrind at 10 to 25 percent is workable in the outer wall of a drainage duct where the duty is lighter.
What is the difference between SN4 and SN8?
SN8 delivers twice the ring stiffness of SN4, and reaching it needs 30 to 40 percent more outer wall thickness or a 15 to 20 percent deeper rib at a shorter pitch. The cost difference is 12 to 20 percent per meter, which is why the class should follow the burial survey.
How long does installation and commissioning take?
From arrival to a stable production run takes three to six weeks for a single line, including foundation work, utility connection, block trials and operator training. Allow another four to eight weeks before the crew reaches steady yield, because startup scrap typically runs 12 to 25 percent in the first two months.
Conclusion
A PE corrugated pipe extrusion line for telecommunication cable protection conduit is best understood as a matched pair of extruders feeding one corrugator, because the liner controls how easily the cable pulls and the rib profile controls whether the duct survives the ground. Neither half can compensate for the other, and a line bought on extruder size alone will disappoint at both ends.
The economics are driven by resin at 72 to 78 percent of cost, so the purchasing conversation and the wall profile matter more than the machine price, and the second lever is utilization rather than automation. A line running 1,500 kilometers a year spreads 0.94 million US dollars of equipment over enough meters to reach a 1.20 to 1.80 US dollar cost, while the same line at half that volume cannot compete on price at any margin.
Wanplas recommends starting with one diameter family, one ring class and one resin grade, funding the block sets and the working capital together with the machine, and requiring a four hour acceptance run on the buyer’s own compound before shipment. A line configured that way can later add a second block set, a larger corrugator or a straight length stacker without replacing its extruders.
