Construction Machinery Seats
Two mechanical construction machinery seats for excavators, loaders, dozers and rollers. KL02 is a high back with full-body and head support, built for heavy plant. YS2-8 folds forward at 27.5 degrees and publishes 80 mm of suspension travel. Send three measurements of your operator station and the weight range of the people who run the machine, and within 48 hours you get which of the two goes on — a pedestal or a slew console is a different order from a plain floor plate.
What the cab and the ground ask for
The roof line, the ground and the length of the shift are imposed by the machine. Each one rules in something a general-purpose machine seat would not offer.
Inside a cab the height above the seat is set by the roof line and the door aperture, not by a guard a few hundred millimetres above the head. That is what makes a genuine high back possible: KL02 carries full-body and head support as a structural specification, not a trim upgrade — which is why the roof clearance measurement comes before the model.
On earthmoving, loading and compaction the seat answers the ground continuously:
There is no flat floor phase to recover in, so published suspension travel is a figure to read: YS2-8 publishes 80 mm, and what that number protects has its own section.
A plant operator is in the seat for the shift, turning to watch an attachment for much of it, with the load path running through the lumbar region into the frame. A low back with soft damping does not become uncomfortable at hour eight — it becomes a back complaint at month eight, a cost that never appears on the purchase order that caused it.
The two models
One is chosen for support across a long shift, the other for travel, adjustment range and getting into a tight cab. A dash below means the figure is not published for that model.
Mechanical suspension, high back with full-body and head support, specified for heavy plant. The model to start from where the operator is in the cab for the whole shift and the roof line allows a tall backrest.
Mechanical suspension. The backrest folds forward at 27.5 degrees, which lets the seat come out of the way in a cab with a low door aperture or a windscreen that has to be reached.
A dash means the figure is not published for that model, not that the model lacks the item. Suspension travel and mounting dimensions are assembly-critical, so they are answered against your three measurements rather than estimated here.
Publish a number that turns out to be wrong and the seat arrives, the batch does not go on, and the machine waits.
A seat chosen for the first hour of the shift is judged in the ninth, by the person who has to climb back into it tomorrow.
What only you can measure
Bolt spacing decides whether a seat can be attached at all. These three decide whether it can be used once it is, and only you can take them.
Send the three below plus the weight range of the people who run the machine; what a fitment answer contains is set out once, for every machine family.
"Too tall for the cab" and "wrong mounting interface" are different problems, and only one of them is solved by taking the other model.
On plant the seat rarely sits on a plain flat deck. It may be any of three, and they are not interchangeable:
A console moves the armrest-mounted controls with the seat, so a replacement has to respect the console interface, not just the floor. Photograph it with something in frame for scale.
Measure from the seat mounting surface to the cab roof lining, and note the door aperture height separately. Those two decide whether the KL02 high back is usable or ends up against the lining. The aperture matters as much as the roof: a seat that fits the cab but will not pass the opening has to be dismantled to install — once per unit, across the batch.
Both models are mechanical, so on a 24 V machine the seat is a passive assembly. The only thing that puts it on the circuit is operator presence sensing — what the presence circuit changes is settled before the order, not at goods-in.
Eighty millimetres
Suspension travel is the distance the mechanism can absorb before the operator starts taking the input directly. On broken ground that distance does structural work — and only if the weight adjuster has been set.
Inside the travel, the mechanism takes the input.
Beyond it the frame takes it and passes it on — a suspension at the end of its stroke transmits more than no suspension would, because what arrives is an impact rather than a movement. So the figure is read against duty cycle, not comfort: spoil, a rutted yard and a roller drum are three different demands on the same 80 mm.
The 50–130 kg band exists because spring rate has to match the person in the seat. Set light, the suspension bottoms out on inputs it should have absorbed; set heavy, it barely moves and the travel is decorative. On a machine handed between shifts that is a two-second task at handover which belongs to somebody, and usually belongs to nobody.
Travel is assembly-critical: it decides how much clearance the seat uses at the top of its stroke. A seat that clears the lining at rest can still meet it under load, which is why the roof clearance measurement is taken with the door shut and answered against your cab rather than against a general rule.
Settled before the order
The one item on a construction machinery seat with a safety function, and the one most often handled as an assumption instead of a question.
Nothing electrical is expected from the seat, and a seat delivered with a harness on it is a seat with a loom nobody will connect. This is the simpler case and it is the more common one on mechanical plant seating.
The circuit runs through a sensor in the seat and a connector at the base, and the machine will not enable travel or the hydraulics without it. Here the connector type and the harness slack are part of the specification, not accessories added afterwards.
Neither error shows at goods-in:
Both are found by an operator at the start of a shift, and across the entire batch at once, because a batch is ordered to a single specification. That is why the connector type and the harness slack are asked for before the order.
Order of failure
A construction machinery seat does not fail all at once, and it does not fail where the operator is looking. The sequence is predictable enough to stock against.
All four are built on the same lines as the complete construction machinery seats.
Model against model
Suspension type is not an axis here — both models are mechanical. These five are where a real difference exists.
| Axis | KL02 | YS2-8 |
|---|---|---|
| Backrest | High back, full-body and head support | Folds forward, 27.5 degrees |
| Operator weight adjustment | — | 50–130 kg |
| Suspension travel | — | 80 mm |
| Fore-and-aft adjustment | — | 150 mm |
| Cab access | Fixed high back — needs roof and door-aperture clearance | Backrest folds clear of a low door aperture; height adjustment 60 mm |
Excavator cabs have their own page: excavator seats.
Three of fourteen
The test centre runs fourteen machines on site. These three report on what actually happens to a seat in a plant cab; the other eleven are on the same floor and photograph on request during qualification.
The frame under somebody who is not sitting still.
Abrasion under repeated low load.
Where the operator ends up after the suspension has moved.
On plant the operator is bracing, turning and being moved by the machine for the whole shift. That is a structural load case, not a static one, and it lands in the frame, the backrest mount and — on a high back — the section carrying the head support.
Grit carried into the cab abrades the cover at the same places thousands of times. This bench measures the failure that comes first in the wear sequence.
The seat index point is the reference the cab geometry is measured from. With real travel that point moves through the stroke, and where it ends up connects a seat dimension to the clearance and the sightline the operator gets — which is what makes the roof clearance measurement answerable.
Every bench sits on our own floor and photographs. Ask during qualification and the pictures come by email, one machine at a time — a bench you can look at is more useful than a paragraph claiming strict quality control.
Four site conditions
The site condition does not only pick a cover. It reaches the rail and the belt retractor as well, and those two are the ones nobody asks about until something stops moving.
| Condition | Cover | Rail and suspension | Belt |
|---|---|---|---|
| Open site, no cab door shut | Weather between shifts and UV on the same panel every day | Grit reaches the moving joints in normal use | Retractor exposed to rain as well as dust |
| Dust and aggregate | Abrasion at the seat edges from clothing and boots on every entry | Fines pack into the rail and turn travel notchy | Webbing has to retract cleanly once it is dusty |
| Wash-down and mud | Direct water at the seams rather than on the face | Mechanism hosed with the machine, and how often | Webbing left wet in the retractor |
| Heat and long exposure | Surface temperature at the start of a shift, and what a season does to the material | Lubricant behaviour at cab temperature | Mechanism where the belt anchors |
Give the condition alongside the three measurements and the answer names the model we would put forward for it — or says that the condition sits outside what a standard model is intended for, before quotation rather than after.
The belt column is left out of almost every enquiry, and on YS2-8 the belt is a retractable mechanism rather than a static strap. A retractor that has stopped retracting is the kind of item a site works around instead of reporting, which is how a safety part becomes a habit.
Vibration is not something an operator notices at the end of a shift. It is something an operator has been absorbing since the start of it.
Factory or middleman
Each has an answer that can be given or refused, and the refusal tells you as much as the answer. Ours are below each question. Ask the same three of whoever else is quoting.
Ours is ours. Suspension units are built on the same site as the complete seats, alongside armrests, belts, rails, covers and switches. A supplier who buys the suspension in can quote you a seat and cannot change what is inside it — and on this category the suspension is the part your duty cycle is buying.
It is held, and traced back to the operation or the component batch that caused it before anything moves. Releasing it with a note and watching what comes back is a real policy some suppliers run; know which one you are buying from before a batch goes wrong.
The plant this range does not cover is listed above, and the fitment answer names what fits and what does not, including which measurement ruled a model out. A supplier who has never told you what they cannot do has not yet had the conversation that tells you what they can.
Plant size, the six assembly lines and the four operations under one roof — stamping, welding, foaming and assembly — are set out once, for the whole range.
Held, and sent on request
Both scans travel with the sample quotation for a plant order, and nothing is added to the list between website and quote. What each one covers.
How to start
Bolt a single seat into the specific cab before a batch is built: the interface it stands on, the height above the backrest and the door aperture are proven the first shift somebody runs in it.
Plant specific
Four that are specific to plant. Order quantities are answered under how orders are shaped, export documents under packing and documents, suspension types in suspension seat selection.
Room. On YS2-8 the backrest folds forward, which gets the seat out of the way for access through a low door aperture, for reaching a windscreen or a service point behind the station, and for shipping. It is a cab-access specification, not a recline feature.
Send the three measurements and the operator weight range instead. The reply names which of the two goes on your station and, where one does not, which measurement ruled it out.
It can be. Travel consumes clearance at the top of the stroke, so a seat that clears the lining at rest can still meet it under load. Send the height above the backrest with the door shut and it is answered against your cab rather than against a general rule.
Often. Send what the seat is standing on, the height left above the backrest and the operator weight range. Replacement where the original part has been discontinued is a large share of this category, and it is answered by measurement rather than by a cross-reference table.
Send your mounting measurements
Floor plate, pedestal or slew console; the height left above the backrest with the door shut; whether the machine expects a presence circuit; and who sits in it, lightest to heaviest. Four lines, and the reply names the model.
Lead with the measurement you are least sure of — on plant that is usually the height left above the backrest with the door shut.
24 business hours to a first reply; the named fitment answer follows within 48 hours of your measurements.