NCCCO Counterweight and Ballast Configuration 4

Question 1

What is the purpose of a 'superlift' or 'Mega Wing Lift' counterweight system used on very large crawler cranes?

Accepted Answer

It positions an auxiliary counterweight on an extended mast or ring to dramatically increase lift capacity

Answer

Superlift systems use an extended mast or large radius ring to position additional counterweight far behind the crane, maximizing the counterbalancing moment for ultra-heavy lifts.

Question 2

When assembling counterweight slabs on a large crawler crane at a job site, who is ultimately responsible for verifying that the correct configuration has been installed?

Accepted Answer

The crane operator and the designated person directing assembly

Answer

Under ASME B30.5 and manufacturer requirements, the operator and the qualified/designated person overseeing assembly share responsibility for verifying the correct counterweight configuration before operations.

Question 3

A hydraulic truck crane is configured with full counterweight for a heavy lift. Before traveling to the next pick point on a sloped road, what counterweight action may be required?

Accepted Answer

Remove some or all counterweight per the manufacturer's travel-with-load guidelines to prevent rear tipover on the grade

Answer

On a downhill grade with full counterweight and no load, the crane's rearward weight bias can cause backward tipover; manufacturers often specify reduced or removed counterweight for sloped travel.

Question 4

What information must be confirmed on the counterweight identification plate or marking before accepting slabs from a rental yard for use on a specific crane?

Accepted Answer

The slab weight, part number, and compatibility with the specific crane model and serial number

Answer

Counterweight slabs must match the crane's specified part number and weight to ensure load chart validity; using incorrect slabs voids the manufacturer's ratings.

Question 5

During a ring crane lift, the ballast ring rotates with the superstructure. What is a primary ground-bearing concern unique to ring cranes compared to conventional crawler cranes?

Accepted Answer

The rotating ballast ring applies concentrated moving loads around a large circumferential path that must be verified for ground bearing capacity

Answer

As the ballast ring rotates, it applies heavy moving loads around the entire ring circumference, requiring ground bearing capacity verification along the full ring path.

NCCCO (National Commission for the Certification of Crane Operators) Practice Test

NCCCO (National Commission for the Certification of Crane Operators) Practice Test

NCCCO Counterweight and Ballast Configuration 4