Fail-safe

General

A provision designed to automatically stop or safely Bridge Crane Control any motion in which a malfunction occurs. (CMAA Spec. 70)

Field wiring

General

The wiring required after erection of the crane. (CMAA Spec. 70)

Fixed axle

Bridge Crane

An axle which is fixed in the truck and on which the wheel revolves. (CMAA Spec. 70)

Fixed Transfer Section

See Crossover. (ANSI MH 27.1-1981)

Fixed transfer section (also known as crossover)

Monorail

A connecting track with an interlock mechanism on both ends, mounted between two interlocking cranes, used to transfer a carrier from one bridge to the other.  (ASME  B30.11-1993)

Fleet angle

Hoist

The angle formed by the wire rope and the drum groove or sheave groove in the plane which contains the wire rope and is parallel to the drum or sheave axis. (WCH)

Floor Bridge Crane Controlled

Bridge Crane Control

Motor propelled units which are Bridge Crane Controlled by an operator on the floor by means of pushbutton station suspended from the overhead equipment. (ANSI MH 27.1-1981)

Foot walk

Bridge Crane

The full length walkway with handrail and toeboards, at­tached to the bridge or trolley for access purposes. Not to be confused with an access platform (usually a short  platform provided only to access endtruck).

Force, breakaway

Below hook device

— the force that must be applied to a magnet to remove it from a piece of ferromagnetic ma­terial to which it is magnetically attached.  (ASME B30.20-1985)

Fork

Below hook device

A mechanical device for use on interlocking transfer equipment to mechanically prevent passage.  (ANSI MH 27.1-1981)

Friction-type pressure gripping lifters

Below hook device

Lifters that grip the load without significant or harmful permanent de­formation of the load surface (see Figs. 17 through 21).  (ASME B30.20-1985)

Gantry crane

Bridge Crane

A crane similar to an overhead crane except that the bridge for carrying the trolley or trolleys is rigidly supported on two or more legs running on fixed rails or other  runway. (CMAA Spec. 70)

Gantry leg

Bridge Crane

The structural member which supports a bridge girder or end tie from the sill. (ASME B30-17)

Gauge

Bridge Crane

The center-to-center distance between the load carrying flanges of the two crane girders of a double girder crane. (ANSI MH 27.1-1981)

Girder, auxiliary (outrigger)

Bridge Crane

An additional girder, either solid or latticed, arranged parallel to the bridge girder(s) for supporting the foot-walk, Bridge Crane Control panels, operator’s cab, etc., to reduce the torsional forces such loads might otherwise impose. (WCH)

Girder, bridge

Bridge Crane

The principal horizontal beam(s) of the crane, which supports the trolley, is supported by the end trucks, and is perpendicular to the runway. (WCH)

Girder, drive (girder “a”)

Bridge Crane

The bridge girder to which the bridge motor and gearcase(s) are attached. For cranes having a drive on each girder, it is the girder to which the Bridge Crane Control panels and/or the  cab are attached. (WCH)

Girder, idler (girder “b”)

Bridge Crane

The bridge girder which does not have the bridge drive attached, but which usually carries the bridge conductors. (WCH)

Girder, runway

Bridge Crane

A horizontal beam attached to the building columns or wall, and supporting a runway rail on which the crane travels. (WCH)

Glide switch (sliding switch)

Monorail

A track switch with a movable end frame containing straight and/or curved sections of track. The inner frame can be slid to align these sections of track with other tracks for routing carriers from one track to another. (ANSI MH 27.1-1981)

Grip ratio

Below hook device

The ratio of the sum of the horizontal forces on one side of the load to the live weight of the load. For example, if the total horizontal force on one side of the load is  100,000 lb. and the live load is 50,000 lb. the grip ratio is 2. For purposes of this calculation, the weight of the load does not include the weight of the lifter (see Fig. I).  (ASME  B30.20-1985)

Gripping force

Below hook device

The force the lifting device exerts on the load.  (ASME B30.20-1985)

Ground fault

Bridge Crane Electrical

An accidental conducting connection between the electrical circuit or equipment and the earth or some conducting body that serves in place of the earth. (CMAA Spec. 70)

Guide, chain

Hoist

A means to guide the load chain at the load sprocket.  (ASME B30-16-1993)

Hand chain

Hoist

The chain provided to Bridge Crane Control move­ment of a hand chain operated trolley.  (ASME HST-4M-1991)

Hanger rod 

Monorail

A steel rod which, together with other fittings, is used to suspend the track from the support­ing structure.  (ASME B30.11-1993)

Hanger rod.

Bridge Crane & Monorail

Steel rods which, together with other fittings, are used to suspend the track from the supporting structure. (ANSI MH 27.1-1981)

Hazardous (classified) locations

Regulatory

Locations where fire or explosion hazards may exist. Locations are classified depending on the properties of the flammable vapors, liquids or gases. or combustible dusts or fibers which may be present and the likelihood that a flammable or combustible concentration or quantity is present. Refer to ANSI/NFPA 70.

—     Class I locations

—     Locations in which flammable gases or vapors are or may be present in the air in quan­tities sufficient to produce explosive or ignitable  mix­tures

—     Class 2 locations

—     Locations that are hazardous be­cause of the presence of combustible dust

—     Class 3 locations

—     Locations that are hazardous be­cause of the presence of easily ignitable fibers or filings, but in which such fibers or filings are not likely  to be in suspension in the air in quantities sufficient to pro­duce ignitable mixtures. (ASME B30-16-1993)

Headroom

Hoist

Headroom is measured with the load hook at its upper limit of travel and is the distance from the saddle of the load hook to the following locations (see Fig. 1)

—     (a)  centerline of the suspension holes on lug sus­pended hoists [see Fig. 1, sketch (a)];

—     (b)  saddle of the top hook on hook suspended hoists [see Fig. 1, sketch (b)];

—     (c)  bottom of the beam on trolley suspended hoists [see Fig. 1, sketch (c)];

—     (d)  supporting surface on base and deck mounted hoists [see Fig. 1, sketch (d)];

—     (e)  uppermost point of hoist on wall and ceiling mounted hoists [see Fig. 1, sketches (e) and (f)]. .  (ASME HST-4M-1991)

High temperature service

General

A condition where the sur­face to which the vacuum pad (or pads) is attached is above 250⁰F (120⁰C). (ASME B30.20-1985)

Hoist

Hoist

A suspended machinery unit which is used for lifting or lowering a freely suspended (unguided) load.  (ASME HST-4M-1991)

Hoist motion

Hoist

That motion which lifts or lowers a load.  (ASME B30-17)

Hoist speed

Hoist

Hoist speed is the rate of motion that the load hook attains while lifting rated load.

Hoist, auxiliary

Hoist

A supplemental hoisting unit, usually of lower load rating and higher speed than the main hoist.  (ASME B30-17)

Hoist, main

Hoist

The primary hoist mechanism provided for lifting and lowering the rated load of the crane. (WCH)

Holding brake

Hoist

A friction brake for a hoist which is automatically applied and prevents motion when power is off.  (ASME HST-4M-1991)

Hook approach

Bridge Crane & Hoist

The minimum horizontal distance between the center of the runway rail and the hook. (CMAA Spec. 70)

Hook approach, end

Bridge Crane & Hoist

The minimum horizontal distance, parallel to the runway, between the centerline of the hook(s) and the face of the wall (or columns) at the end of the building. (WCH)

Hook approach, side

Bridge Crane & Hoist

The minimum horizontal distance, perpendic­ular to the runway, between the centerline of a hook (main or auxiliary) and the centerline of the runway rail. (WCH)

Hook suspended

Hoist

Suspension of hoist from a trol­ley or rigid structure by means of a hook(s) at top of hoist.  (ASME HST-4M-1991)

Hook to hook approach

Bridge Crane

Hook; latch type

Hoist

A type of hook with a mechanical device to bridge the throat opening of the hook.  (ASME HST-4M-1991)

Horizontal lift

Below hook device

A condition where the surface to which the vacuum pad (or pads) is attached is in a horizontal plane.  (ASME B30.20-1985)

Idler sheave

Hoist

A sheave used to equalize tension in oppo­site parts of a rope. Because of its slight movement, it is not termed a running sheave. (CMAA Spec. 70)

Impact allowance

Bridge Crane

See Impact Factor.

Impact factor

Bridge Crane & Hoist

Additional hook load assumed to result from the dynamic effect of the live load. (CMAA Spec. 70)

Inch (inching)

Bridge Crane & Hoist

See “jog”. Often used incorrectly to refer to “creep speed”.  (WCH)

Indentation-type pressure gripping lifters

Below hook device

Lifters that carry the load by applying force to indent the sides of the load (see Figs. 15 and 16).  (ASME B30.20-1985)

Indicator, internal Bridge Crane Control function

Below hook device

An indicator which shows that the permanent magnet material in one type of electrically Bridge Crane Controlled permanent magnet has been positioned internally to provide full magnetic  at­traction.  (ASME B30.20-1985)

Inductive load

Below hook device

An electrical load which has a lagging power factor. (ANSI MH 27.1-1981)

Industrial duty crane

Bridge Crane & Hoist

Service classification covered by CMAA Specification No. 70, ‘Specifications for Electric Overhead Traveling Cranes’. (CMAA Spec. 70)

Ingot turnover grab

Below hook device

A manipulating lifter (see Fig).  (ASME B30.20-1985)

Insulation class

Bridge Crane & Hoist

Motor winding insulation rating which indicates its ability to withstand heat and moisture. (CMAA Spec. 70)

Interlock mechanism.

Bridge Crane & Monorail

A mechanical device to lock together the adjacent ends of two cranes or a crane to a crossover or spur track to permit the transfer of carriers from one crane or track to the  other.

Interlocking crane

Bridge Crane & Monorail

A crane with an interlock mechanism on one or both ends enabling it to be mechanically locked to another crane, crossover, or spur track for the purpose of transferring a carrier from one to another. (ANSI MH 27.1-1981)

Interlocking mechanism 

Monorail

A mechanical device to lock together the adjacent ends of two cranes, or a crane to a fixed transfer section or spur track, to per­mit the transfer of carriers from one crane or track to the other.  (ASME B30.11-1993)

Inverter (variable frequency drive)

Bridge Crane Control

A method of Bridge Crane Control by which the fixed line voltage and frequency is changed to a three-phase system with infinitely variable voltage and frequency. (CMAA Spec. 70)

Jib boom 

Bridge Crane

A horizontal cantilever track for support­ing the carrier.  (ASME B30.11-1993)

Jog (inch)

Bridge Crane & Hoist

To move the hook, trolley, or bridge in a series of short, discontinuous, increments by momentary operation of a Bridge Crane Controller. (WCH)