FREE NCCCO Tower Crane Erection, Climbing, and Dismantling Questions and Answers

Question 1

When erecting a tower crane, what is the most important reference for determining the correct torque values for structural bolts?

Accepted Answer

The manufacturer's erection manual

Answer

The manufacturer's erection manual provides the specific, engineered torque requirements for all structural connections. Relying on any other source could lead to improper assembly and catastrophic failure, as these values are calculated based on the bolt grade, size, and the forces they will endure.

Question 2

According to most manufacturers, at what wind speed should tower crane erection or dismantling operations typically be suspended?

Accepted Answer

As specified by the manufacturer, but generally not exceeding 20-25 mph

Answer

Wind imposes significant dynamic loads on crane components during assembly. Manufacturers specify a maximum wind speed for these operations, which is often around 20-25 mph, to ensure the safety of the crew and the stability of the partially assembled structure. Always consult the specific crane's manual as this is the governing document.

Question 3

During a tower crane climbing operation, what is the correct sequence after the climbing frame has lifted the upper part of the crane?

Accepted Answer

Insert the new tower section, install and torque all connecting bolts, then lower the crane onto the new section

Answer

The proper sequence is critical for stability. After the crane is jacked up, the new mast section is slid into place. Then, all structural bolts must be installed and torqued to the manufacturer's specification before the weight of the upperworks is transferred onto the new section.

Question 4

Who is ultimately responsible for verifying that the tower crane's foundation has reached the required compressive strength before erection begins?

Accepted Answer

The Erection Director / Lift Director

Answer

The Erection Director is responsible for the entire erection process, which includes confirming all prerequisites are met. This involves obtaining and reviewing documentation, such as concrete test reports, to ensure the foundation meets or exceeds the manufacturer's specifications before any crane components are placed on it.

Question 5

When dismantling a tower crane, what is generally the first major component to be removed after the crane is prepared?

Accepted Answer

The counterweights

Answer

The dismantling sequence is designed to maintain stability at all times and is often the reverse of erection. Removing the counterweights first is a critical step to balance the crane properly for the subsequent removal of the jib and other major components, preventing a nose-heavy condition.

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

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

FREE NCCCO Tower Crane Erection, Climbing, and Dismantling Questions and Answers