It’s 8:00AM, you stand donned in a full body clean-suit, mask covering your face, bonnet and hood constantly threatening to work their way into your eyes.
The task of the day?
Safely lifting a multi-billion-dollar suite of one-of-a-kind science instruments and carefully placing it on a fragile carbon fiber structure for fastener installation so that the newly integrated module can be then lifted and relocated; new center of gravity and all.
As you survey the clean room, various other priceless pieces of hardware lie in various states of assembly, engineers and technicians busily moving between electrostatic discharge protected operating tables. You are about to perform a very critical lift.
Over months of planning, the engineering team has considered every challenge, every risk, and prepared for every eventuality. With a detailed plan in hand spanning dozens of pages; a trained and prepped team with you, and Safety & Quality Assurance watching over your shoulder, you’re ready to perform a lift that can impact the fate of an entire mission.
Lucky for you, in addition to proper training and personnel, you now have an ace up your sleeve in the form of AXIS, the world’s most capable and reliable below-the-hook (BTH) device.
But before we get ahead of ourselves,
A critical lift refers to any lifting operation that involves significant risk. And when a lift is critical, it requires sufficient planning, appropriate safety measures, and potentially critical rigging.
Although terms like “significant” and “critical” can be subjective, there are some criteria and guidelines established by OSHA, ASME, and industry specific standards (such as NASA-STD-8719.9) to accurately assess lift criticality. In the most general terms, a lift becomes critical when particular challenges of the planned operation introduce significant risk to cost, schedule, or safety.
Critical lifts require additional detailed planning and controls to ensure the safety and success of the operation. In order to better understand what we mean by risks, let’s briefly explore some key and common challenges associated with critical lifts:
a. Personnel Safety
Human safety is paramount during any lift. Any crane operations involving lifting of personnel, or in which personnel are required to be exposed to danger as a consequence of lifting operations will classify a lift as critical.
Image courtesy of NASA.
b. Approaching the load rating
Perhaps the most common consideration when identifying a lift as critical is when payload weight approaches equipment limitations.
Per OSHA, lifts exceeding 75% of the rated capacity of the crane or derrick are considered critical. More generally, it is useful to assess risk associated with operations which may strain the capabilities of the crane, hoist, BTH equipment, or rigging when planning a lift.
c. Environmental challenges
Lifts that will be performed in proximity to potential hazards should always be assessed for criticality. Some examples include lifting in close proximity to power lines, steam pipes, pressurized vessels, fuel lines, etc.
Additionally, environmental hazards which seem more benign also have the potential to impose risk to the operation, such as lifting over operational areas, sensitive areas, or in tightly enclosed spaces. Although the risks are less obvious in these cases, a minor equipment or operator error could still have major consequences for hardware or personnel.
d. High value or mission-critical payloads
Any time the lifted load is extremely valuable (see personnel safety above), a lift’s criticality must be assessed. And in many industries and sectors, payload safety is mission critical.
Whether lifting a highly volatile pressurized container, nuclear fueling, or life-saving medical equipment, the margin of error and consequences to follow demand the utmost care. This includes not only careful planning and a well-prepared team, but also superior equipment capability and precision to maintain complete control.In the aerospace industry, for example, lifts of spaceflight hardware are almost invariably unique, mission critical, and complex.
Often, custom made lifting hoists, slings, and structured apparatuses are required to safely perform necessary lift operations. And each custom BTH device will often take months of engineering, analysis, and development, introducing significant expense and risk to schedule should there be an issue at any of these steps.
Image courtesy of NASA.
At NEWTON, we recognize the risks and challenges associated with critical lift operations and understand their potential impact for multiple areas like Safety; Engineering, Development, or Production Planning; Budgeting, Quality Management and Assurance, and more.
Our experience with critical lifts in-house or on-site at GSFC (Goddard Space Flight Center), JSC (Johnson Space Center), and other mission locations provides key insight into the nature of these challenges. And our solution is AXIS: the most capable critical lift rig ever made.
AXIS with transport legs deployed.
AXIS is a heavy-duty, remote-controlled Below-The-Hook structured sling lift developed from NASA heritage (including the JWST mission) in accordance with ASME B30 that has been engineered for unparalleled capability, repeatable precision, safety, and reliability.
To provide a new standard for critical lifts, AXIS solves:
a. Personnel Safety Concerns
AXIS employs multiple redundant fail-safe mechanisms and heavy-duty hardware to reduce critical lift risks while protecting both personnel and payloads.
As a remote-controlled unit, lifts with AXIS also require less personnel exposure in the vicinity of the operation and the lifted subject. And because AXIS controls its orientation with unprecedented levels of precision even while mid-lift, it further limits personnel exposure by reducing the amount of set-up rigging and de-rigging required for critical lifts.
b. Load Rating Limits
With a large Safe Working Load (SWL) of up to 25,000 lb (11,340 kg), AXIS allows for operations without typical concerns of approaching equipment capacity.
With its heavy-duty rollers, trolleys, dual motors, and other features coming together to deliver full performance under load even while lifting weights up to 2x that of the JWST, or 5x that of the Roman Space Telescope; AXIS is ready to handle the largest next-gen spacecraft, instruments, and more.
Image courtesy of NASA.
c. Environmental Challenges
Safety and reliability are at the core of AXIS’s DNA.
Reliability analysis-driven design includes safety features ranging from redundant sensors and electrical systems to redundant back-drive failsafe mechanisms. Lifted loads are redundantly protected against back-drive or other loss of control via the implementation of worm gears and electronic toothed brakes.
Remote operation via a custom GUI packaged in our mobile control cart offers operational flexibility, allowing control up to 100 ft away from the action. Remote control is performed with full confidence of payload control thanks to redundant live readouts of angular position down to one-one hundredth of a degree. And even AXIS’s contamination shield supports the safety of the lifted load, acting as a last line of defense even in the case of an oil leak or other contaminant risk imposed by the lift equipment itself.
d. Complete Control for Mission-Critical, High-Value Payloads
AXIS provides a minimum ± 5° range of angular adjustment under load for a first-of-its-kind mid-lift level of control that delivers critical lifts with unparalleled precision and operational efficiency.
AXIS also achieves an extreme level of accuracy down to ± 0.01° degrees via redundant readouts, and offers additional back-drive prevention that is not reliant on friction to ensure that even the most critical payloads will remain under complete control throughout any operation.
Many individual factors can combine to impact the criticality of a particular crane operation including the payload’s weight, dimensions, location; personnel exposure, and/or environmental conditions. Each of these factors, and any operation-specific risks must be properly assessed in preparation for a critical lift. Any one or combination of these or other factors which influence the risk associated with a lift operation can be sufficient designate a lift as critical.
Critical lifts require additional planning, oversight, and safety measures to prevent accidents, equipment damage, or operational failures. Proper risk assessment, detailed planning, situational awareness and the right hardware for the job are essential levers to move your payloads and your business forward.
AXIS represents a new standard for under-the-hook device control and versatility, significantly decreasing risk in critical lifts. It provides the capabilities and levels of control that development and production operations in multiple sectors need to solve the challenges posed by overhead lifts. If you’d like to learn more, please contact us, and visit our AXIS product page here.
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