Final answer:
Multiple lift rigging, or Christmas treeing, refers to a construction method for lifting multiple objects simultaneously, which saves time and improves efficiency on construction sites. It is a specialized rigging setup requiring balance and secure attachment of loads using a crane with multiple hooks or attachment points.
Step-by-step explanation:
Multiple lift rigging, also known as Christmas treeing, is a method used in construction to lift and place multiple objects simultaneously. This process helps in saving time and improving efficiency by allowing for multiple loads to be moved in a single lift cycle. It's commonly used in scenarios where various materials, like beams, pipes, or other components, need to be hoisted to various heights or locations on a construction site.
In practice, multiple lift rigging requires a special setup that includes a lifting device, such as a crane, equipped with multiple hooks or attachment points. These attachment points connect to slings or other rigging devices that hold the objects being lifted. It is essential for the rigging to be properly balanced and for each load to be securely attached to ensure safety during the lifting process.
The term should not be confused with the similar-sounding practice in the oil and gas industry, where a 'Christmas tree' refers to the arrangement of valves, spools, and fittings installed on top of the wellhead after drilling has been completed, which control the flow of oil and gas.