ASME B30.20:2010 pdf free download

ASME B30.20:2010 pdf free download.Below-the-Hook Lifting Devices.
operation of vacuum lifting devices, such as excessively high or low ambient temperatures, exposure to adverse weather corrosive fumes, dust-laden or moisture-laden atmospheres, and hazardous locations.
four-pad powered vacuum lifter: see Fig. 20-0.4-1, illustration (d).
four—pad powered vacuum lifter manipulator: see Fig. 20-0.4-1, illustration (e).
horizontal surface lift: a condition where the surface to rhich the vacuum pad (or pads) is attached is in a
horizontal plane.
ni ii ltiple-pad mecha ii ical vacu ii in lifter: see Fig. 20-0.4-1, illustration (c).
nonporous material: a material that is not permeable by fluid.
porous material: a material that is permeable by fluid. seal ring (seal): that part of the vacuum pad which forms the seal of the vacuum chamber between the vacuum pad body or vacuum lifting device and the attached material.
service, heavy: service that involves operation within the rated load limit that exceeds the limits of normal service.
service, normal
Design Category A lifters (for ASME BTH-1): service that involves operation with various weights within the rated load limit with not more than four operations above 65% of the rated load limit per 24-hr period.
Design Category B lifters (for ASME BTH-1): service that involves operation with various weights within the rated load limit, averaging less than 65% of rated load limit.
service, severe: service that involves normal or heavy service with abnormal operating conditions.
service, special or infrequent: service that involves operation other than normal, heavy, or severe.
single-pad mechanical vacuum lifter: see Fig. 20-0.4-1, illustration (b).
two-pad mechanical vacuum lifter: see Fig. 20-0.4—1, illustration (a).
vacuum: pressure less than ambient atmospheric pressure.
vacuum Ifter: a below-the-hook lifting device for lifting and transporting loads using a holding force by means of vacuum (see Fig. 20-0.4-1).
vacuum manipulator: a vacuum lifter capable of repositioning the load while suspended.
vacuum pad: a device that applies a holding force on the load by means of vacuum.
vacuum reservoir: the evacuated portion of the vacuum system that functions to compensate for leakage into the vacuum system or to provide a vacuum reserve in the event of vacuum generator failure.
Chapter 20-3 applies to the marking, construction, installation, inspection, testing, maintenance, and operation of all lifting magnets when used for single or multiple steel piece handling operations in which the operator of the lifting magnet is required to manually position the lifting magnet on the load and manually guide the load during its movement, or in remotely operated lifting magnets when operated in close proximity to people. For multi-magnet systems where individual lifting magnets are suspended from a spreader beam or its equivalent, this section applies only to the individual lifting magnet, excluding the spreader beam or its equivalent and the associated control equipment. This Chapter does not apply to remotely operated lifting magnets in areas where people are excluded during normal operation.
SECTION 20-3.2: MARKING, CONSTRUCTION, AND INSTALLATION
20-3.2.1 Marking
(a) Rated Load (Capacity)
(1) General Application Lifting Magnets. The rated load (capacity) of the lifting magnet shall be legibly marked on the lifting magnet or on a tag attached to the lifting magnet where it is visible. This marking shall refer to the instruction manual for information relating to decreases in rating due to the load surface condition, thickness, percentage of contact with the lifting magnet, temperature, metallurgical composition, and deflection.
(2) Specified Application Lifting Magnets. The rated load (capacity) of the lifting magnet shall be legibly marked on the lifting magnet or on a tag attached to the lifting magnet where it is visible. This marking shall refer to the specific loads for which this rating applies.
(b) Controls. The position of the control switch or handle of a lifting magnet shall be marked with “Lift,”“Off,” and “Drop,” or equivalents to indicate the mode of operation of the lifting magnet.
(c) Identification. All new close proximity operated lifting magnets shall be provided with identification displaying, but not limited to, the following information:
(1) manufacturer’s name and address
(2) manufacturer’s model and lifting magnet unit identification number
(3) weight of lifting magnet.