Sorting and gripping

Clamshell bucket

Two shells that close vertically.
It is the tool for what has to be taken from above:
where a bucket cannot tip, it can go down.

Other names for this tool: hydraulic clamshell bucket, two-shell grab, shell bucket, bivalve bucket, grab bucket, clamshell grab, rope grab (for the suspended version).

The essentials

Family: Sorting and gripping
Classes (t): 1 to 100 t
Coupler: We calculate it with you for your machine
Power source: Hydraulic — flow and pressure: we calculate it with you for your machine
Functions: Closing, often + rotation
Use: Narrow excavation, shaft

Compare with the grapple →

01 Use

What it is for

**Left:** the clamshell bucket goes straight down the shaft and comes back up closed.
**Right:** in a narrow shaft, the bucket hits the walls and can no longer scrape.
What sets it apart:
the movement is vertical from start to finish — it goes down, closes, and comes back up.
Computer-generated image.

A bucket takes material by scraping:
it attacks at an angle, then tips.
That movement calls for room and for something to bear on.
In a shaft, a chamber, a narrow foundation excavation or a hopper, that room does not exist.

The clamshell bucket, for its part, goes straight down, closes on the material and comes back up. The movement is vertical from start to finish — that is what makes it usable where the tool can neither tilt nor bear on anything.

Narrow deep excavations, shafts and chambers, cleaning out hoppers and silos, taking up heaps from above, work under a slab or between two walls:
everywhere the constraint is verticality, not power.

Not to be confused with the scrap grapple. The grapple has four or five open tines:
it is made to catch a volume that holds together — scrap, stumps, bulky waste.
The clamshell bucket has two solid shells that meet:
it is made for loose material that flows — soil, rubble, sand, mud. Taking one for the other means either letting everything slip between the tines, or not being able to grasp anything at all.

02 What we check with you

On which machine?

A clamshell bucket fits excavators from 1 to 100 t.
The coupler and the exact excavator class: we calculate them with you for your machine.

What the tool does

It is used for narrow excavations and shafts.
Its shells close to grip, and it often rotates too.
The volume, the permitted load, the width, the opening and the weight: we calculate them with you for your machine.

What is needed on the hydraulic side

It needs a hydraulic connection.
The circuit, the flow and the pressure, for opening, closing and rotation: we calculate them with you for your machine.

Figures taken from our models on the market.
Your study sets the exact value for your machine.

Don't have these figures?
A photo of the machine is enough to start.

03 Your study

Have your machine checked.

Give us your excavator model, the number of auxiliary lines already fitted, the depth to be reached and the material to be taken up.
Tell us too whether you are working between walls:
that is what separates the rigid bucket from the suspended one.

What we need to answer you

Your machine Its make and its tonnage.
The auxiliary circuit Its flow in l/min, its pressure in bar, single- or double-acting.
The coupler in place Its system and its class.
The work The use, and the material.

Without these details, the study still begins: we will ask you for them.

Send my photos

or describe your need

Book an appointment with the specialist

Or call 01 84 16 55 49 · our lines are open 7 days a week, from 7h to 22h.

Written study within 3 working days, once the file is complete.

04 Choice

What determines the choice

01 — Rigid or suspended This is the first question, and it decides all the rest.
Mounted rigidly on the end of the dipper arm, the bucket is positioned to the centimetre and you can press on it to penetrate firm ground. Suspended from a chain or a rope, it gains a great deal in depth but you lose the push and the precision:
it now only goes down and takes what is there.
02 — The volume and the shape of the shells The volume is read in litres, like a bucket.
The shape counts as much:
toothed shells attack firm soil, smooth and close-fitting shells hold back fines and liquid.
A toothed bucket that closes badly lets the sand escape.
03 — The rotation In a narrow excavation, the machine cannot be moved to orient the grab:
it is the tool that has to turn.
Continuous hydraulic rotation is what makes the bucket really usable in an excavation — but it adds one more function to feed.
04 — The number of functions to feed Closing alone:
one line.
Closing and rotation:
two, or one line and a switching block. This is the point that most often makes the fitting fail, long before a question of size or weight.

05 Check

What is checked before ordering

What your machine can feed Number of auxiliary lines actually fitted, flow and pressure available.
A second function is not added afterwards without work being done.
The depth you have to reach It is read on the machine's working range, arm and tool included — not on the data sheet of the tool alone.
It is the figure we are given least often, and the one that decides.
Working over a drop A full bucket, arm extended above a void, is the most unfavourable position for stability.
The permissible load is read on the machine's load chart, at the real reach.
What you are taking Soil, rubble, sand, mud, waste:
the material sets the shape of the shells and the usable volume.
A heavy loose material rarely fills the bucket to the brim.
The interface Coupler type and size, or pin dimensions.
The tool is supplied with the matching plate — see the couplers.

Neighbouring tools

Before taking

For which trade

To go further

Family: Sorting and gripping
Compatibility: The seven criteria in detail →