CS-410 is a self-contained coiled-tubing micro-bore plant: a coil reel, a hydraulic straightener, a clamp-and-push stroke drive and an entry guide, pushing a fibre-guided steerable head into ground with no line, no map and no signal.
CS-410 is not a machine that rides into the hole. It stays where the crew is and pushes one continuous tube, and one head on the end of it, into the ground ahead.
Coiled tubing in the ~38–60 mm (1.5–2.375 in) class, wound on a drum and paid out under tension as the bore advances. The only thing aboard that is consumed.
A roller station that takes the reel-set curvature out of the tube before the drive sees it. That work is charged against the tube's life.
A clamp grips the straightened tube, a stroke advances it a fixed increment, the clamp releases and resets. No connection is made between strokes.
It sets the initial heading and bridges the open span between drive and ground. Past it there is a head on the string, and nothing else.
Everything that decides a bore sits on the surface, in reach of the two or three operators who are the whole crew. The power pack is diesel-hydraulic, with an electric-hydraulic option, and the plant works from −40 °C to +40 °C. The bore is in the ~50–150 mm (2–6 in) class, and on the conduit mission the tubing that followed the head in is the delivered product: conduit, left in the bore.
Hard engineering concentrates in a machine a crew can stand beside and repair; the part that goes into unknown ground is a length of tube and a head.
CS-410 names two arrangements. Type A is the micro-bore plant this page describes; Type B is the direct pipe boring system. They are different drive architectures at different scales, not variants of one drive.
Type A, the micro-bore plant. A clamp grips the tubing, a stroke advances it a fixed increment, the clamp releases and resets. It takes tube in the ~38 mm to 60 mm class, sets its heading at an entry guide, and displaces the face rather than cutting it.
Type B, the direct pipe boring system. Dual hydraulic pinch and high thrust push rams on an HDD-style top drive layout, taking 2 inch to 4 inch tube off a level-wound reel and launching through a reinforced kelly tube on a hinge. It is 11,800 mm long over the bed and stands the launch tube at 12°.
| Type B | What the arrangement carries |
|---|---|
| Overall | 11,800 mm long, 2,650 mm high, 2,550 mm wide |
| Launch | A reinforced kelly tube, heavy wall and wear lined, hinged at 12° and set hydraulically through 0°–20° |
| Reel | 2 inch to 4 inch coiled tubing, hydraulic level-wind, powered pay-off and tension control |
| Feed | Top feed from the reel over low-friction rollers, maintaining centreline into a multi-roll straightener |
| Drive | Dual hydraulic pinch and high thrust push rams, HDD-style top drive layout, full length support |
| In the tube | The launch tube, a wear liner, the coiled tubing and centralizers |
| Head | Steering capable, all-formation, replaceable cutters, and a through-bore that carries the tubing |
The Type B arrangement as it is drawn: the envelope, the launch tube, the reel, the feed, the drive and the head.
What the two arrangements share is the family's shape: a plant that stays on the surface, one continuous tube, and a head on the end of it. What they do not share is a number. A push, a bore class or a reach quoted for one is not a figure for the other. Everything below is Type A.
CS-410 and CS-411 are the same machine sent to two different jobs. One plant, one clamp-and-push stroke drive, one coil reel, one fibre-guided steerable head; what differs is the ground and the configuration.
What does not change. The drive family is one body of engineering rather than two. The soft-string mechanics that march load from the head back to the surface, the relations that decide when a pushed tube goes sinusoidal and then helical, the first-yield-inside-the-helix cap on push and the reel bend-strain lever that sets tube life all carry across unchanged — properties of a coil tube in a hole, not of a mission.
What the application changes. The head, the ground and the fluid duty. Here the head displaces the face and the soil goes into the wall; on the civil application it cuts, and the cuttings come back. Here the cover is shallow, five metres nominal; there it is deep. Here the fluid lubricates; there it carries cuttings. Those three move the numbers further than the physics does, so a figure belonging to one application is never carried onto the other.
A buyer is not choosing between two products with two spare-parts lists; they are choosing which job to put one machine to. Aquifer CS-411 is the second application, with its own figures.
The tube is the drive member, the guide path and the umbilical at once. Lube, fibre and payload travel down the one bore, and that is what lets the plant work with no radio and nothing downhole that needs charging.
Fed down the tube to relieve the face and lubricate the tube in its own bore — the analogue of drilling-fluid delivery, and what buys the ground envelope.
Downhole attitude out, the operator's steering in, and the breadcrumb back out. On the conduit mission it is part of the product left in the bore.
Mission hardware travels down the tube rather than in a body cavity. Beside a centralized fibre unit the largest rigid article is a Ø13–18 mm slug.
At the working end is a steerable compaction head carrying a directional-drilling bit face, tricone or polycrystalline-diamond to suit the formation, larger in diameter than the tube behind it — and the overcut is what gives the tube its annular clearance and the lube its path. Steering is the directional-drilling inheritance at this scale: an asymmetric face, oriented at the head, so pushing without orientation deviates and pushing with it steers.
The seam between tube and head carries thrust, bending, retrieval tension and all three services at once, and it is defined once so a new head is a module change.
The method is displacement boring. Soil is compacted and displaced radially to form the bore as the head advances, and there is no spoil return, no cuttings to manage and no trench.
Almost everything else follows from that one choice. There is no mucking out, because nothing was cut loose to be carried back, and no cuttings-transport duty, so the fluid system aboard is a lubrication and annulus-fill system, not a mud plant. There is no spoil pile at the entry and no open cut across whatever the bore passes under.
It sets the head's shape too: the head comes back out through the bore it made, so its profile is retrievable by construction, with no back-facing shoulders to anchor it in the wall. And it sets the ground envelope — push alone suits soft to firm ground, and denser ground is bought at the face rather than at the drive. The drive was never the bottleneck. The face always is.
Mechanically the drive advances one metre per twenty-five-second cycle, 144 m/h; the face is always slower, at ~3–8 m/h, formation-dependent. A continuous tube has no connection to make between strokes.
Hydraulics make thrust cheap. A Ø100 mm cylinder at 200 bar delivers 157.1 kN and the tube yields in pure axial compression at 193.0 kN, so neither obvious limit governs.
A ring of wall thickness t squeezed between two opposed line loads forms four plastic hinges. Virtual work gives a collapse line load of Fyt²/R per unit of gripped length — the squeeze a flat jaw can apply before it flattens the tube it is holding. Multiply by die friction for the push it can transmit, and that is the lowest of the three.
| Coiled tubing | Squeeze limit, 0.40 m die | Grip at die friction 0.30 | Half the yield-in-helix cap | Governs |
|---|---|---|---|---|
| 31.75 × 2.77 mm | 106 kN | 31.9 kN | 36.3 kN | The clamp |
| 38.10 × 3.18 mm — short and medium load | 117 kN | 35.0 kN | 54.6 kN | The clamp |
| 50.80 × 3.96 mm — long load | 136 kN | 40.7 kN | 102.4 kN | The clamp |
Flat dies, on the tube classes the plant draws from.
So the adopted surface push takes the lower branch: 35.0 kN on the 38.10 mm tube and 40.7 kN on the 50.80 mm one. A bigger tube buys stiffness, weight and reel size and no push at all, because Fyt²/R barely moves across standard coiled-tubing geometries — grip sits between 32 and 41 kN across the whole board.
Which makes the die the cheapest engineering on the platform. A matched-radius die spreads the squeeze as pressure rather than as a line load and lifts the bound directly, and it saturates: past a conformity factor of about two the helix cap takes over.
Inside the bore the wall supports the tube laterally. Between the drive and the ground it supports nothing, and a thin-walled tube in compression over an unsupported span is a column.
Euler on a pinned-pinned span is the right relation, and it is unforgiving because critical load falls with the square of the length. The span decides whether the drive's thrust survives the last metre before the ground.
| Unsupported span | Critical load | Read |
|---|---|---|
| 0.5 m | ~425 kN | Above the tube's own yield |
| 1.0 m | ~106 kN | Above the working class |
| 1.5 m | ~47 kN | Inside the working range |
| 2.0 m | ~27 kN | Limits the whole plant |
The illustrative 38.1 × 3.2 mm tube. Every free span on the board runs at a slenderness of 140 to 168, deep in the long-column range.
Worked against the adopted push, the free span limit is 1.74 m on the 38.10 mm tube and 2.79 m on the 50.80 mm one. On a skid the entry guide sits flush with the frame's own end and the ground, so the span stays short by construction. On a trailer it oversails the tailboard and the span is set by ride height plus deck overhang, checked for that configuration rather than inherited.
That is why the entry guide and its conductor are a costed structural item — 194 kg on the short frame, 258 kg on the long one.
The plant pushes the ground and the ground pushes back, into the frame and out through whatever holds it down. Self-weight is not what holds it down.
At a ground friction of 0.40 the plant's own operating weight reacts 79 per cent of the push at the short load and 105 per cent at the long one, which looks comfortable and is not: friction on a real pad is not a constant, and a wet clay pad sits at the bottom of a credible band with frozen or gravelled ground at the top.
| Tube load | Surface push | Self-weight at friction 0.40 | Across friction 0.20 to 0.55 | With the onboard anchors |
|---|---|---|---|---|
| Short, 380 m | 35.0 kN | 27.6 kN — 79% | 39% to 108% | 2.22× |
| Medium, 630 m | 35.0 kN | 30.6 kN — 87% | 44% to 120% | 2.30× |
| Long, 880 m | 40.7 kN | 42.6 kN — 105% | 52% to 144% | 2.28× |
Self-weight is taken at operating mass, the mass present while the bore is running.
Two reaction anchors at 25 kN each travel with the plant in every configuration, costed into the package at 190 kg with their beam, and they are what closes it — to a consistent 2.22 to 2.30 times. Anchor, between deploy and bore, is a structural verb.
It is also what makes the carrier formats equivalent at the entry guide. Jacked rigid on its drop legs, a trailer becomes a ground-bearing structure for the duration of the bore; wheels, suspension and coupler are not in the reaction path in either format.
Core radius is set by the strain the tube takes every time it crosses the drum, and fatigue is a property of the tube rather than of the mission. Capacity is bought in layers.
Bending strain across the drum is the tube's outside diameter over twice the core radius, and the tube sees half of that as a strain amplitude on each pass. The core that delivers fifty round trips, at 1.147 per cent of amplitude and so 2.30 per cent of bend strain, is 0.83 m on the 38.10 mm tube and 1.11 m on the 50.80 mm one. Length beyond that goes into layers.
| Tube load | Tube on the drum | Core radius | Reel outside diameter | Tube, share of dry mass | Life on a shared drum |
|---|---|---|---|---|---|
| Short | 380 m of 38.10 × 3.18 mm | 0.83 m | 1.97 m | 27% | 93 round trips |
| Medium | 630 m of 38.10 × 3.18 mm | 0.83 m | 2.12 m | 37% | 83 round trips |
| Long | 880 m of 50.80 × 3.96 mm | 1.11 m | 3.13 m | 52% | 73 round trips |
Reel structure is 14–15% of dry mass at every load. Each load reaches 50 round trips on a core of its own.
Tripling the stored length grows the reel outside diameter by ten per cent and the reel structure by fourteen, while the tube mass grows by 132 per cent. The reel is not the heavy part of the plant. The tube is, and it is consumed by handling rather than by service load: a drum is wound core outward, so a long bore unwinds to the core, where strain is worst.
Two operating rules follow. Keep the tube depressurized while it spools, because internal pressure during bending is the steepest published effect on coiled-tubing life. And where the mission allows it, leave the tube in the bore as the conduit product: that deletes the retrieval leg, 27 per cent of the total at the long load, and halves the fatigue spend per bore.
Optical loss over the longest tube load is under 1.2 dB including two connectors, on a technology that runs metro links at forty kilometres. The length was never the difficulty.
A fibre carried inside the tube goes over the drum with it and takes the tube's bend. Strain at a radial offset from the tube axis is that offset divided by the core radius, so where the fibre sits decides whether it survives its first spooling — and telecom fibre proof-tests near one per cent and is designed to about a fifth of one per cent for long life.
A fibre strapped to, bonded into or resting against the wall sees more strain on the drum than any commercial excess fibre length covers. It does not survive the first spooling.
Better by a factor of three and still short. The requirement is a tolerance, held by hardware rather than by intention.
Centralised within a few millimetres of the axis, with at least 0.40 % excess fibre length so the fibre can migrate: a fibre-in-metal-tube unit on centralizers.
One thing here gets easier with length: the long tube load needs a bigger core for its own fatigue life anyway, and a bigger core is a gentler bend for the fibre inside it.
Centralising the fibre also sets the payload envelope. A rigid article has to pass beside a unit sitting on the axis, so the envelope is a Ø13–18 mm slug: a slim sensor node fits, and anything with a body is carried by the head.
Nothing in the package is an allowance where a calculation was possible: the straightener from the roller force that applies the tube's plastic moment, the clamp from the squeeze the push demands, the frame and anchors from the push they react.
| Item | Short load | Long load | What sizes it |
|---|---|---|---|
| Coiled tubing — consumable | 1,041 kg | 4,027 kg | 380 m and 880 m on the drum |
| Reel flanges, ribbed | 286 kg | 725 kg | Stiffness; solid discs would be 477 and 1,208 kg |
| Reel core drum, 6 mm shell | 172 kg | 229 kg | Wrap pressure, external buckling |
| Hydraulic straightener | 234 kg | 375 kg | 29 kN and 64 kN roller force |
| Clamp assembly | 292 kg | 340 kg | 117 kN and 136 kN squeeze |
| Drive frame and stroke cylinder | 360 kg | 394 kg | Reacts 35 kN and 41 kN |
| Entry guide and conductor | 194 kg | 258 kg | Free span, 1.74 m and 2.79 m |
| Reaction anchors | 190 kg | 190 kg | Two at 25 kN, with the beam |
| Hydraulic power unit | 321 kg | 326 kg | 6 kW: push, pump, clamp |
| Package dry | 3,894 kg | 7,709 kg | — |
| Lube in the tank | 3,150 kg | 3,150 kg | 3.0 m³ at every load |
| Package operating | 7,044 kg | 10,859 kg | What travels the road |
| Package less tube | 2,853 kg | 3,683 kg | What the frame is built around |
The medium load sits between the columns: 4,636 kg dry, 7,786 kg operating.
Read the last row against the one above it. The frame is built around 2,853 to 3,683 kg across the family while the operating package spans 7,044 to 10,859 kg, so a frame that takes the reel and the drive takes any of these loads with a tube change.
Which exposes something worth saying. The short and the medium loads are the same machine: same tube, same bore, same clamp, same push limit, same reel core, differing only in 685 kg of consumable and 0.15 m of reel outside diameter. The real break falls at the long load, where the tube changes from 38.10 to 50.80 mm and drags a bigger straightener, clamp, core and frame with it.
The plant is built in three carrier formats — skid, trailer and air-deployable frame. They are three ways of bringing the same machine to the entry line, not three products.
The skid is the tolerant one, and the reason is the load path: no suspension, no tyre sidewall and no coupler between the anchor bolts and the entry guide, and no legal weight or height ceiling of its own. What it needs instead is a crane, 6.0 t at the short load and 11.8 t at the long, planned dry. The pick is not an even four-way split either, because the reel end carries most of the weight.
The trailer is a working platform as well as a way of arriving: the drive is mounted to the deck rather than craned off it, drop-leg jacks bridge the suspension for the bore, and at this gross weight the coupler is a pintle ring rather than a ball.
The air-deployable format wraps the same plant in a shell, a frame, a sacrificial crush stage and a canopy under a printed gross-mass cap of 7,500 kg. One doctrine rule shapes all of it: no pyrotechnics anywhere in the deployment chain, which leaves a mechanical crush stage as the only attenuation available.
The long tube load is not stopped by the ground. It is stopped by a load height and a payload rating, both found by asking how the machine gets to the job.
880 m of the 50.80 mm tube on a 0.70 m drum at a 1.11 m core is nine layers and a 3.13 m reel outside diameter — 4.13 m of load height on a one-metre deck, against a 4.15 m limit. Two centimetres is not a margin. The fix is width rather than height, because a narrower core would cost tube fatigue: a 1.30 m drum gives five layers, a 2.72 m outside diameter and 3.72 m of load height, with 0.43 m of margin inside the 2.55 m width limit.
| Tube load | Skid | Trailer | Air-deployable |
|---|---|---|---|
| Short, 380 m | Closes | 94.6% of payload at operating mass | 4,505 kg gross, 60.1% of the cap |
| Medium, 630 m | Closes | 62.3% dry; 4.6% over once filled | 5,326 kg gross, 71.0% of the cap |
| Long, 880 m | Closes | Over payload even dry, at 103.5% | 209 kg over the cap, bare plant |
Against a single-tire tri-axle at 7,447 kg payload capacity and an air-deployable frame at a 7,500 kg cap. Road limits, no permit: 2.60 m wide, 4.15 m high, 12.5 m long.
The trailer drawn under this plant runs six tyres, one per hub, so it does not reach the tridem highway allowance, which needs twelve or more; the ceiling is the rating of a light single-wheel tri-axle, and the medium load misses it by 339 kg. By air the long load is decided before a crate is drawn, because the bare plant is over the cap dry. One rule follows in every format: the plant travels dry, and 3.0 m³ of lube, 3,150 kg, goes in on site.
Underground the fleet's no-radio, no-GPS doctrine stops being a design choice and becomes a physical fact: rock and soil kill radio outright.
Inclination, toolface and azimuth ride the fibre to the operator continuously, and steering goes back down it. Tier 2 of the fleet's ladder: human in the loop by construction.
The drive counts its own strokes, so distance along the bore falls out of the machine and costs no emission at all — an input a continuous injector does not give.
Inclination and toolface behind the head ride the same thread that steers it, so the operator reads the bore's attitude continuously and nothing is broadcast to get it.
Nothing in the fleet transmits by radio and nothing guides on a link. Human safety runs ahead of everything: the crew is two or three people and all of them stay on the surface; on uncertain ground or a lost attitude read the drive stops and holds; and if a run ends early the string is exactly where it stopped, holding and silent, waiting for a person.
The trade behind the plant is the group's own: three decades of horizontal-directional-drilling practice in-house, on mobile rigs to 1,000,000 lb pull; a baseline of 200–400 m per pull extended past 1,400 m in displaceable soils; and a trenchless record of 149 segments over 31,267 m, averaging 420 m with a longest single segment of 1,032 m. Those are the group's own trenchless bores rather than this plant's.
What a bore reaches is decided by the ground it is in, not by the reel it came off, so reach is discussed against a ground condition rather than as a bare length. The guidance ladder is on the technology page; the rules the fleet is held to are on doctrine. Every design in the family is patent pending, the coil-tube drive machine among them.
It suits a buyer with something to get under and no way over it. A buyer looking for a weapon is at the wrong door.
If you have a crossing that cannot be opened, a conduit to place under something, or ground to reach without a person going into it, the conversation starts with what lies between the two ends.
A conversation starts with a screened enquiry rather than a quotation. Bring the crossing, the cover, what the ground investigation says and what has to be at the far end; we bring the plant, the tube load and the carrier format that suit them. Enquiries are screened, counsel comes first on any international transfer, and permits are taken per shipment.
The Underground family is the whole set, and Aquifer CS-411 is this same machine in its civil application. Who it is for is the buyer's view.
All Underground family designs are patent pending; international transfer is export-controlled and subject to Canadian government permits taken per shipment, and nothing on this page is an offer.
