ASME B30.2 pdf download.Overhead and Gantry Cranes.
SECTION 2-0.1: SCOPE OF B30.2
Volume B30.2 includes provisions that apply to the construction, installation, operation, inspection, and maintenance of hand-operated and power-driven overhead and gantry cranes that have a top-running single- girder or multiple-girder bridge, with one or more top- running trolley hoists used for vertical lifting and lowering of freely suspended, unguided loads consisting of equipment and materials (see Figs. 2-0.2-1 through 2-0.2-5). The requirements included in this Volume also apply to cranes having the same fundamental characteristics such as cantilever gantry cranes, semi-gantry cranes, and wall cranes.
Requirements for a crane used for a special purpose such as, but not limited to, non-vertical lilting service, lifting a guided load, or lifting personnel are not included in this Volume.
(16) SECTiON 2-0.2: DEFINITIONS
alrnorrual opcrutrn writhEnms: environmental condi Lions that are unfavorable, harmful, or detrimental to or for the operation of a crane, such as excessively high or low ambient temperatures, exposure to adverse weather, corrosive fumes, dust-laden or moisture-laden atmospheres, and hazardous locations.
accessor: a secondary part or assembly of parts that contributes to the overall function and usefulness of a crane.
auxiliary hoist: supplemental hoisting unit usually of lower load rating and higher speed than the main hoist.
brake: a device, other than a motor, used for retarding or stopping motion by friction or power means,
brake, holding: a friction brake for a hoist that is automatically applied and prevents motion when power to the brake is off,
SECTION 2-1.10: GUARDS FOR MOVING PARTS
(a) Exposed moving parts, such as gears, set screws, projecting keys, and drive chain and sprockets, which constitute a hazard under normal operating conditions, shall be guarded.
(b) Each guard shall be capable of supporting, without permanent deformation, the weight of a 200 lb (90 kg) person, unless the guard is located where it is not probable that a person will step on it (see
ASME B15.l).
SECTION 2-1.11: TRUCK FRAME DROP
Means shall be provided to limit the drop of bridge and trolley truck frames to I in. (25 mm) in case of wheel, axle, or bearing breakage.
SECTION 2-1.12: BRAKES AND BRAKING MEANS
2-1.12.1 HoIst Holding Brakes
(a) Each hoisting unit of the crane shall be equipped with at least one holding brake. The holding brake shall be applied to the motor shaft or a gear reducer shaft and shall have a torque rating not less than the percentage of rated load hoisting torque at the point where the brake is applied as follows:
(1) 125% of rated load hoisting torque when used with a control braking means other than mechanical
(2) 100% of rated load hoisting torque when used with a mechanical control braking means
(3) 100% of rated load hoisting torque for each brake if two holding brakes are provided
(b) For a crane that handles molten material, each hoisting unit that handles or tips molten material shall be equipped with one of the following arrangements:
(1) Two holding brakes shall be provided, one of which is applied to a gear reducer shaft, plus control braking means. Each holding brake shall have a torque rating not less than 100% of rated load hoisting torque at the point where the brake is applied.
(2) One holding brake shall be provided if the hoisting unit has a mechanical load brake or a control braking means that provides controlled lowering of the load upon loss of power. The holding brake shall have a torque rating not less than 150% of rated load hoisting torque at the point where the brake is applied.
(C) When an auxiliary hoist is not to be used to handle or tip molten material, one hoist brake may be used as per (a)
(d) Each hoist holding brake shall have thermal capacity for the frequency of operation required by the service.
(e) Hoist holding brakes shall be applied automatically when power to the brake is removed.
(f) Hoistholdingbrakesshallbeprovided with means to adjust for lining wear.
ASME B30.2 pdf download
