SINGLE-ROPE / RELEASE SEQUENCE

Single-Rope Clamshell Grab Bucket

A single lifting rope simplifies the crane connection, but the bucket's opening sequence becomes the key selection question. Some mechanisms need the grab to be set down on the material or floor before they release; do not assume it can empty while suspended. Show us the actual pickup and discharge positions so the right release mechanism can be checked.

Red two-jaw clamshell grab bucket shown complete on a plain background — Two-jaw clamshell grab, overall form01 / 02

ROPE INTERFACE: One lifting rope
MODEL EXAMPLES: XZ5 / U82
DISCHARGE: Mechanism-dependent
ORDER BASIS: Checked release cycle

Simple rope interfaceDischarge method reviewed

Request a configured quote View specifications

Send the lifting-hook or rope drawing, the point where the grab must open, cargo density, maximum mass, working height and required cycle frequency.

One-unit enquiries welcome

The selected attachment's minimum order and supply scope are confirmed in the written offer.

Crane and attachment checked together

Review the loaded attachment, connection, operating cycle and site clearances before approval.

Clear delivery and support scope

Agree inspection, documents, packing, schedule, site support and warranty before order placement.

01 / SPECIFICATIONS

Check model scale and release sequence together.

The two example configurations serve very different crane sizes. Check the actual opening mechanism, grab self-weight and discharge point on the selected unit.

Swipe to compare the complete selected-unit parameters →

Model	Crane rating	Bucket volume	Material density	Listed material per grab	Rope / reeving
XZ5, toothed	3 t	0.5 m³	≤1.2 t/m³	0.6 t	Ø15 mm / ratio 2
U82	25 t	15 m³	≤1 t/m³	15 t	Ø28 mm / ratio 3

Listed material mass is not grab self-weight. The model examples do not establish that every single-rope grab can release while hanging. Confirm the selected mechanism and total loaded mass in the approved drawing.

Rope and outline data for these configurations

Model	Rope / sheave arrangement	Outline dimensions
XZ5	Ratio 2; Ø160 mm sheave	H 2,169 / D 1,470 mm
U82	Ratio 3; Ø460 mm sheave	H 8,000 / D 5,800 mm

H and D are outline labels. Use the approved unit drawing for installation clearances, opening width and building work.

Must the bucket touch down before it opens?

That depends on the release mechanism. Some single-rope grabs require the bucket to land or slacken before releasing. Tell us whether discharge must occur over an open hopper without landing, so this can be specified correctly.

Review the configuration

Red and black clamshell grab bucket photographed in a factory — Clamshell grab in the factory

02 / APPLICATIONS

Use only where the release path is workable.

Small bulk stations

A compact toothed grab can handle loose material where the lifting arrangement and discharge point permit its release sequence.

Large open stockpiles

A higher-volume design can suit a larger crane, but cargo density, bucket mass and operating clearance govern usable capacity.

Existing crane retrofit

A single rope may reduce the need for a separate closing drum. The hook, lifting height and release action still need engineering review.

If you need powered opening over a hopper while the bucket remains suspended, compare a suitably engineered powered or multi-rope grab before ordering. Compare the matching crane system.

03 / CONFIGURATION

Choose the attachment around the actual lift.

Define the complete pickup and discharge sequence before selecting a single-rope mechanism. The chosen bucket must fit the crane hook and rope, available headroom, cargo load and the way the operator will release material at the discharge point.

01 / RELEASE METHOD

Define exactly how the bucket opens

Write down whether the bucket may land at discharge or must open in the air; test the selected mechanism against that sequence.

Landing surface
Hopper height
Operator control

02 / LOAD SELECTION

Include bucket mass

Check maximum filled cargo against the selected grab self-weight and the crane rating at the actual operating condition.

Density and filling
Total suspended load
Crane capacity

03 / ROPE AND HOOK

Match the lifting connection

Confirm rope size, reeving, hook eye, swivel and headroom against the existing crane arrangement.

Rope diameter
Hook connection
Lift travel

04 / SHELL GEOMETRY

Reach the material and discharge

The shell opening, digging profile and closed height should clear obstacles at both ends of the cycle.

Toothed or plain edge
Open width
Closed height

Ask each supplier to quote the same material, crane interface, operating cycle and delivery boundary for a meaningful comparison.

Request a matched offer

04 / QUOTATION SCOPE

Compare a complete attachment package.

Equipment price, crane modifications and site services should be separated so your team knows what is supplied and what remains to be done locally.

Grab mechanism

Identify the shell, single-rope head, latches, rope fittings and any required reset or release components.

Crane connection

Confirm lifting rope, hook, swivel, headroom and the allowable loaded mass.

Operating proof

Agree a demonstration of the specified pickup and discharge sequence, documents, packing and service parts.

05 / ORDERING & DELIVERY

Approve the selected unit before manufacture.

The offer should connect your load data to one drawing, one equipment schedule and a clear inspection and handover plan. Production and freight dates are confirmed for that selected configuration.

Request these documents with the offer

Selected grab drawing and release sequence
Self-weight and maximum material load
Rope, hook and reeving information
Open and closed dimensions
Factory demonstration or agreed test procedure
Operating and maintenance instructions

List the destination standards and customer witness points before finalising the acceptance plan.

01
Application review
Confirm load, crane interface, environment, operating sequence and buyer requirements.
02
Drawing approval
Approve dimensions, self-weight, selected components, controls and site responsibilities.
03
Build and inspect
Complete the agreed functional and load-case checks, records and packing.
04
Deliver and commission
Coordinate transport, unloading, installation checks, operator instruction and handover.

MINIMUM ORDER

Ask for one configured unit

Single-unit enquiries are welcome. The written offer confirms the selected design's minimum order and exactly what is supplied.

CERTIFICATION & TESTS

Specify the destination

State applicable market and customer requirements. The offer lists the documents, inspections and tests available for the selected unit.

LEAD TIME

A project schedule in writing

Drawing approval, production, inspection and shipping are separate milestones. A dated delivery programme follows the selected configuration.

WARRANTY & AFTER-SALES

Know the support terms before shipment.

Agree the warranty period and start date, covered components, replacement parts, installation guidance and any on-site service in the signed offer.

Ask for support terms

01 / INSTALLATION

Match the crane interface

Assign who supplies power, rope, hook connection, controls, rigging and commissioning equipment.

02 / ACCEPTANCE

Test the stated load case

Agree inspection and functional checks around the material and lift the attachment was selected for.

03 / SPARES

Maintain the installed unit

Record the final model, serial number and wear parts so replacement components fit the supplied configuration.

06 / RELATED EQUIPMENT

Compare the attachments that fit your load.

View the full attachment range

07 / BUYER QUESTIONS

Questions to settle before buying.

Use these answers to prepare one technical and commercial brief for the selected unit.

Discuss this attachment

Can any single-rope grab empty above a hopper?

No. Some mechanisms rely on landing or slack rope. The required discharge position must be stated before the opening system is chosen.

Is the U82 suitable for my 25 t crane?

The U82 example is paired with a 25 t crane and 15 t of material, but the selected grab self-weight, connection, duty and geometry must still be confirmed.

Does one rope mean no control changes?

Not necessarily. The release sequence, travel limits and operator method may still require changes. Review the existing crane and the selected grab together.

What material information is needed?

Give bulk density, moisture, particle size, abrasiveness, target mass per lift and any mixed-material operating cases.

What is included in one-unit supply?

The quotation should identify the grab mechanism, rope fittings, drawings, tests, spares, packing, delivery and written support terms.

YOUR EQUIPMENT BRIEF

Request a Single-rope grab technical offer.

Send the lifting-hook or rope drawing, the point where the grab must open, cargo density, maximum mass, working height and required cycle frequency. The selected drawing and commercial offer can then identify the attachment, crane interface, documents, delivery and support.

Send my attachment enquiry ↗

Include these project details

01 Cargo, density and largest lumps
02 Crane rated load and hook/rope drawing
03 Pickup depth and discharge height
04 Whether the bucket may land at release
05 Lift frequency and operating environment
06 Destination and required tests

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Single-rope grabSelected for your load

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