FSG 31 Bearings

Question 1

What is Federal Supply Group 31?

Accepted Answer

FSG 31 is the Federal Supply Group (formally known as NATO Supply Classification Group NSG 31) in the USA for supply items codified in the category of Bearings.

Question 2

What is NATO Supply Classification Group 31?

Accepted Answer

NSG 31 is the NATO Supply Classification Group (also known as Federal Supply Group FSG 31 in the USA) for supply items codified in the category of Bearings.

Question 3

Which Federal Supply Classes are in FSG 31?

Accepted Answer

FSG 31 contains the following Federal Supply Classes (FSC) (formally known as NATO Supply Classification Class [NSC]): 3120,3130,3110

Question 4

Which NATO Supply Classification Classes are in NSG 31?

Accepted Answer

NSG 31 contains the following NATO Supply Classification Classes (NSC) (also known as Federal Supply Class [FSC] in the USA): 3120,3130,3110

Question 5

When did the transition from Federal Supply Groups (FSG) to NATO Supply Groups (NSG) occur?

Accepted Answer

The transition from Federal Supply Groups (FSG) to NATO Supply Groups (NSG) occurred on January 1, 1997. This change was implemented to align the classification and coding systems used by NATO member countries for military supplies and equipment. Federal Supply Groups (FSG) are now obsolete.

Question 6

What is a Spherical Plain Bearing?

Accepted Answer

A Spherical Plain Bearing (BEARING,PLAIN,SPHERICAL) is a detachable part in or on which a journal, gudgeon, pivot, or the like moves. It is used to carry a load and to reduce sliding friction. It does not employ rolling elements. It may be divided into two or more segments of 180 degrees (3.141 radians) or less. The item has a cylindrical bore and is basically spherical in its exterior design to allow for shaft misalignment. Excludes BEARING, PLAIN, SELF-ALIGNING.

Question 7

What is a Sleeve Bearing?

Accepted Answer

A Sleeve Bearing (BEARING,SLEEVE) is a tubular shaped item with or without flange(s) designed to reduce friction and carry a kinetic load on the surface(s) parallel to the axis of the bore.  It must have a visible or detectable means of lubrication or be self-lubricated.  The over all length must exceed 25 percent of the outside diameter or the shortest distance between peripheral flats of the body, except for straight tubular (without flange or shoulder) items having a bearing surface(s) parallel to the axis of the bore only.  Includes items which are divided into two or more segments which include 180 degrees (3.141 radians) or less of the bearing periphery.  See also BUSHING, SLEEVE; SPACER, SLEEVE; and WASHER (as modified).  Excludes PIN, HOLLOW.

Question 8

What is a Sleeve Bushing?

Accepted Answer

A Sleeve Bushing (BUSHING,SLEEVE) is a tubular shaped unthreaded item with or without a flange at one end designed to be inserted into a hole to reduce the inside diameter of the hole and to protect the surrounding body structure from damage resulting from stress, strain, and/or vibration. The overall length must exceed 25 percent of the outside diameter or the shortest distance between peripheral flats of the body. Includes items which are divided into two or more segments which includes 180 degrees (3.141 radians) or less of the bearing periphery. For items made of rubber, see BUSHING, NONMETALLIC. See also BEARING, SLEEVE; BUSHING, TAPERED; SPACER, SLEEVE; INSULATOR, BUSHING; and BUSHING, ELECTRICAL CONDUCTOR. Excludes BUSHING, DRILL, JIG.

Question 9

What is a Self-Aligning Plain Bearing?

Accepted Answer

A Self-Aligning Plain Bearing (BEARING,PLAIN,SELF-ALIGNING) is a detachable assembly in or on which a journal, gudgeon, pivot, or the like moves. It is used to carry a load and to reduce sliding friction. It does not employ rolling elements. The item consists of a bored precision ground ball (or spherical plain bearing) around which an outer ring is fitted. The assembly may be either separable or nonseparable. Excludes BEARING, PLAIN, ROD END and BEARING, PLAIN, SPHERICAL.

Question 10

What is a Rod End Plain Bearing?

Accepted Answer

A Rod End Plain Bearing (BEARING,PLAIN,ROD END) is a detachable assembly in or on which a journal, gudgeon, pivot, or the like moves. It is used to carry a load and to reduce sliding friction. It does not employ rolling elements. The outer member of the assembly is modified to provide a shank. The inner member may be either a plain spherical bearing or a sleeve bearing. Excludes BEARING, PLAIN, SPHERICAL and BEARING, PLAIN, SELF-ALIGNING.

Question 11

What is a Railway Axle Plain Bearing?

Accepted Answer

A Railway Axle Plain Bearing (BEARING,PLAIN,RAILWAY AXLE) is a block of brass or bronze lined with antifriction metal, which serves as a bearing surface, carrying the weight of the railway car and resting on the axle journal.

Question 12

What is a Thrust Washer Bearing?

Accepted Answer

A Thrust Washer Bearing (BEARING,WASHER,THRUST) is an item of any peripheral shape usually having one flat or spherical surface and a centrally located hole. It is designed for applications involving moving (kinetic) loads. Except for items fabricated from bearing quality synthetic (plastic) or composed of multilayer material, one bearing surface must either have a specific surface finish designation of 32 microinch (0.8 micrometre) or less, arithmetical average (aa) (arithmetic mean deviation) or one of the following conditions: be lapped or ground; have visible or detectable means of lubrication; grooves, indentations; or self-lubrication. The thickness must not exceed 25 percent of the outside diameter of the shortest distance between peripheral flats (when thickness and/or outside diameter is designated as a tolerance dimension, the maximum dimension will be used to determine compliance). Excludes straight, tubular (without flange) items having a bearing surface(s) parallel to the axis of the bore only. See also WASHER, FLAT and SPACER, SLEEVE.

Question 13

What is a V Bearing?

Accepted Answer

A V Bearing (BEARING,V) is a cylindrical device, primarily designed to furnish a bearing surface for a low-speed oscillating shaft. The item consists of a precision machined or inclosed V or modified V groove and may include a drilled hole for spring loading.

Question 14

What is a Sleeve Bearing Blank?

Accepted Answer

A Sleeve Bearing Blank (BEARING BLANK,SLEEVE) is an item usually cylindrically shaped with or without a flange. It is designed to be drilled after installation and used as a BEARING, SLEEVE. Excludes items in bulk form. See also BUSHING BLANK.

Question 15

What is a Sleeve Bearing Half Set?

Accepted Answer

A Sleeve Bearing Half Set (BEARING HALF SET,SLEEVE) is two or more identical or different sizes or types of BEARING HALF, SLEEVE packaged or grouped together for single issue as a unit, for replacement of worn and/or damaged bearings. See BEARING HALF, SLEEVE. Excludes BEARING SET, SLEEVE.

Question 16

What is a Sleeve Bearing Set?

Accepted Answer

A Sleeve Bearing Set (BEARING SET,SLEEVE) is two or more identical or different sizes or types of BEARING, SLEEVE packaged or grouped together for single issue as a unit, for replacement of worn and/or damaged bearings. See BEARING, SLEEVE. Excludes BEARING HALF SET, SLEEVE.

Question 17

What is a Sleeve Bearing Half?

Accepted Answer

A Sleeve Bearing Half (BEARING HALF,SLEEVE) is a half of a two-piece split type BEARING, SLEEVE.

Question 18

What is a Linear-Rotary Motion Roller?

Accepted Answer

A Linear-Rotary Motion Roller (ROLLER,LINEAR-ROTARY MOTION) is a cylindrical body having a centrally located hole to accommodate a pin or shaft for attachment to a push rod guide, yoke, rocker arm, turntable, or rail. The item provides a rolling contact with the face of a valve stem, or the lobes of a cam ring or camshaft on engines, fuel injection pumps, latches, turntables, parallel bearing surfaces requiring a roller support, and the like. Excludes BEARING, ROLLER, CYLINDRICAL; ROLLER, ELECTRICAL SWITCH; and friction bearings. See also CAM FOLLOWER, NEEDLE BEARING.

Question 19

What is a Mechanical Equipment Bearing Replacement Parts Kit?

Accepted Answer

A Mechanical Equipment Bearing Replacement Parts Kit (PARTS KIT,BEARING REPLACEMENT,MECHANICAL EQUIPMENT) is a parts kit consisting of one or more bearings or bearing assemblies, which are issued as a unit for repair/replacement. It may include gasket(s), O-ring(s), race(s), seal(s), spacer(s), washer(s), or the like.

Question 20

What is a Track Roller Plain Bearing?

Accepted Answer

A Track Roller Plain Bearing (BEARING,PLAIN,TRACK ROLLER) is a detachable assembly consisting of an outer and inner ring, designed for use in a track roller or similar application. It is used to carry a load and reduce sliding friction. It does not employ rolling elements, but may incorporate non-metallic liners or sleeves to aid in reducing friction and/or providing lubrication. See also BEARING, BALL, TRACK ROLLER; and BEARING, ROLLER, TRACK ROLLER. Excludes BEARING, PLAIN, SPHERICAL and BEARING, PLAIN, SELF-ALIGNING.

Question 21

What is a Cam Follower Plain Bearing?

Accepted Answer

A Cam Follower Plain Bearing (BEARING,PLAIN,CAM FOLLOWER) is a detachable assembly, which provides rolling contact with a cam or similar device, and converts reciprocating or oscillating motion to linear motion. The assembly consists of an outer ring and and integral stud. It does not employ rolling elements but may incorporate nonmetallic liners or sleeves to aid in reducing friction and/or providing lubrication. See also CAM FOLLOWER, NEEDLE BEARING.

Question 22

What is a Jewel Bearing?

Accepted Answer

A Jewel Bearing (BEARING,JEWEL) is an item generally round in shape and usually having a centrally located hole. It has at least one flat bearing surface. It is made of precious or semi-precious gem (ruby, sapphire and the like), natural or synthetic. It is intended for use in precision instruments, meters, timing devices, clocks, and the like.

Question 23

What is a Thrust Washer Bearing Half?

Accepted Answer

A Thrust Washer Bearing Half (BEARING HALF,WASHER,THRUST) is a half of a two-piece BEARING, WASHER, THRUST.

Question 24

What is a Thrust Pad?

Accepted Answer

A Thrust Pad (PAD,THRUST) is a rigid, replaceable metal item, designed for assembly with a component to resist wear caused by direct thrust exerted by an associated part. The bearing surface must have a specified surface finish designation of 16 micro-inches centreline average (arithmetical average) or less.

Question 25

What is a Thrust Washer Bearing Set?

Accepted Answer

A Thrust Washer Bearing Set (BEARING SET,WASHER,THRUST) is a collection of identical or similar BEARING, WASHER, THRUST designed to be used for replacement of worn and/or damaged washers.  Excludes WASHER ASSORTMENT.

Question 26

What is a Stern Tube Bearing Assembly?

Accepted Answer

A Stern Tube Bearing Assembly (BEARING ASSEMBLY,STERN TUBE) is an assembly consisting of staves, anode, bearing, housing and the like.  It supports a rotating propulsion shaft.

Question 27

What is a Sleeve Bushing Half?

Accepted Answer

A Sleeve Bushing Half (BUSHING HALF,SLEEVE) is a half of a two piece split type BUSHING, SLEEVE.

Question 28

What is a Pillow Block Cap?

Accepted Answer

A Pillow Block Cap (CAP,PILLOW BLOCK) is an item designed to be affixed to a base, forming a housing for a removable bearing or the bearing may be an integral part of the housing. It is used to prevent the admission of dirt and/or foreign matter, retain the lubricant and to position a shaft or the like.

Question 29

What is a Ball Bearing Unit?

Accepted Answer

A Ball Bearing Unit (BEARING UNIT,BALL) is an assembled unit, composed of a housing incorporating a single or multiple row ball bearing(s), designed to meet various or specific conditions of mounting.

Question 30

What is a Plain Bearing Unit?

Accepted Answer

A Plain Bearing Unit (BEARING UNIT,PLAIN) is an assembled unit, composed of a housing incorporating a plain bearing, or bearings, designed to meet various or specific conditions of mounting.

Question 31

What is a Roller Bearing Unit?

Accepted Answer

A Roller Bearing Unit (BEARING UNIT,ROLLER) is an assembled unit, composed of a housing incorporating a single or multiple row roller bearing(s), designed to meet various or specific conditions of mounting.

Question 32

What is a Bearing Unit Housing?

Accepted Answer

A Bearing Unit Housing (HOUSING,BEARING UNIT) is a single or multiple piece item without ball, plain or roller bearing(s). It is designed to meet various or specific conditions of mounting. For items with bearings, see BEARING UNIT, BALL; BEARING UNIT, PLAIN; and BEARING UNIT, ROLLER.

Question 33

What is a Strut Tube Bearing Assembly?

Accepted Answer

A Strut Tube Bearing Assembly is an assembly consisting of staves, anode, bearing, housing, and the like to support a rotating propulsion shaft in the aft part of the hull.

Question 34

What is a Bearing Housing Liner?

Accepted Answer

A Bearing Housing Liner (LINER,BEARING HOUSING) is a rigid tubular item which fits between a bearing and its housing, designed primarily as a replaceable wear surface within the inner wall of the housing.

Question 35

What is an Elastomeric Bearing?

Accepted Answer

An Elastomeric Bearing (BEARING,ELASTOMERIC) is a flexible and resilient composite laminated block which consist of a series of elastomer layers bonded and reinforced with metal plates.  It is the connection between a structure and its support and is designed to provide dampening and&#47;or movement in various axis within dynamic components.

Question 36

What is an Annular Ball Bearing?

Accepted Answer

An Annular Ball Bearing (BEARING,BALL,ANNULAR) is a cylindrical device in which the inner or outer ring turns upon a single or double row of hardened balls which roll easily between the two rings, thus minimizing friction. For items with faces specially ground for duplex mounting see BEARING, BALL, DUPLEX. Excludes BEARING, BALL, AIRFRAME.

Question 37

What is a Cylindrical Roller Bearing?

Accepted Answer

A Cylindrical Roller Bearing (BEARING,ROLLER,CYLINDRICAL) is a nonadjustable roller bearing consisting of a single or multiple-row of hardened cylindrical rollers and a retainer used with or without inner or oute r rings. Excludes BEARING, ROLLER, AIRFRAME.

Question 38

What is a Self-Aligning Roller Bearing?

Accepted Answer

A Self-Aligning Roller Bearing (BEARING,ROLLER,SELF-ALIGNING) is an antifriction bearing having a cylindrical rolling element and one spherical raceway which will adjust to varying degrees of shaft and/or support misalignment without damage to the raceways and permits the full rating of the bearing to be utilized.

Question 39

What is a Journal Roller Bearing?

Accepted Answer

A Journal Roller Bearing (BEARING,ROLLER,JOURNAL) is an item in which the shaft or revolving part turns upon hardened rollers usually contained in a cage. It must contain an inner or outer race, or both. For items without a race(s), see RETAINER AND ROLLER, BEARING.

Question 40

What is a Thrust Ball Bearing?

Accepted Answer

A Thrust Ball Bearing (BEARING,BALL,THRUST) is an antifriction bearing having a ball rolling element, designed to resist axial thrust, or to support an axial load. Excludes BEARING, BALL, PIVOT.

Question 41

What is a Thrust Roller Bearing?

Accepted Answer

A Thrust Roller Bearing (BEARING,ROLLER,THRUST) is an antifriction bearing having a roller rolling element, designed to resist axial thrust, or to support an axial load.

Question 42

What is a Tapered Roller Bearing?

Accepted Answer

A Tapered Roller Bearing (BEARING,ROLLER,TAPERED) is a cylindrical device in which the inner cone or outer cup turns upon a single or double row of tapered hardened rollers which roll easily in a race, thus minimizing friction and designed to carry a radial load and capable of sustaining axial thrust. Excludes BEARING, ROLLER, THRUST.

Question 43

What is a Tapered Roller Bearing Cone?

Accepted Answer

A Tapered Roller Bearing Cone (CONE,TAPERED ROLLER BEARING) is an inner component of a tapered roller bearing which provides a contact surface for the rolling elements of the bearing.

Question 44

What is a Tapered Roller Bearing Cone And Rollers?

Accepted Answer

A Tapered Roller Bearing Cone And Rollers (CONE AND ROLLERS,TAPERED ROLLER BEARING) is an assembled inner component of a tapered roller bearing, consisting of a cone (which provides a contact surface for the rolling elements of the bearing), a complement of tapered rollers (the rolling elements), and frequently a retainer (which spaces the rolling elements).

Question 45

What is a Tapered Roller Bearing Cup?

Accepted Answer

A Tapered Roller Bearing Cup (CUP,TAPERED ROLLER BEARING) is an outer component of a tapered roller bearing which provides a contact surface for the rolling elements of the bearing.

Question 46

What is a Bearing Adapter Sleeve?

Accepted Answer

A Bearing Adapter Sleeve (ADAPTER SLEEVE,BEARING) is an adapter sleeve used to mount and locate an antifriction bearing on a straight shaft permitting wide tolerances of shaft diameter and making it unnecessary to heat the bearing or use a press for mounting.

Question 47

What is an Inner Bearing Ring?

Accepted Answer

An Inner Bearing Ring (RING,BEARING,INNER) is the inner component of a ball or roller bearing which provides a contact surface for the rolling elements of an antifriction bearing.

Question 48

What is an Outer Bearing Ring?

Accepted Answer

An Outer Bearing Ring (RING,BEARING,OUTER) is the outer component of a ball or roller bearing which provides a contact surface for the rolling elements of an antifriction bearing.

Question 49

What is a Bearing Seat?

Accepted Answer

A Bearing Seat (SEAT,BEARING) is a rigid item usually circular in shape, designed to accommodate a bearing. It positions the bearing but does not encase it or restrain its motion.

Question 50

What is a Bearing Ball Retainer?

Accepted Answer

A Bearing Ball Retainer (RETAINER,BALL,BEARING) is a frame or inclosure which spaces and retains the rolling elements of a BEARING, BALL (as modified).

Question 51

What is a Bearing Roller Retainer?

Accepted Answer

A Bearing Roller Retainer (RETAINER,ROLLER,BEARING) is a frame or inclosure which spaces and retains the rolling elements of a BEARING, ROLLER (as modified).

Question 52

What is a Bearing Retainer And Balls?

Accepted Answer

A Bearing Retainer And Balls (RETAINER AND BALLS,BEARING) is an assembled inner component of a ball bearing, consisting of a frame or inclosure which spaces and fixes the position of the rolling elements of a BEARING, BALL (as modified) and the spherical bodies which are the rolling elements in a BEARING, BALL (as modified).

Question 53

What is a Bearing Retainer And Rollers?

Accepted Answer

A Bearing Retainer And Rollers (RETAINER AND ROLLERS,BEARING) is an assembled inner component of a roller bearing, consisting of a frame or inclosure which spaces and retains the rolling elements of a BEARING, ROLLER (as modified) and the rollers which are the rolling elements in a BEARING, ROLLER (as modified).

Question 54

What is a Bearing Ball?

Accepted Answer

A Bearing Ball (BALL,BEARING) is a homogenous spherical body, a series of which provides the rolling elements in a BEARING, BALL (as modified). The item is designed primarily to alleviate friction. It may have other usages such as the checking component in a ball-type check valve. Excludes BALL, CHECK; BALL, VALVE, PORTED.

Question 55

What is a Bearing Roller?

Accepted Answer

A Bearing Roller (ROLLER,BEARING) is a cylindrical body of either solid or hollow construction which provides the rolling elements in the roller bearing.

Question 56

What is a Needle Bearing Cam Follower?

Accepted Answer

A Needle Bearing Cam Follower (CAM FOLLOWER,NEEDLE BEARING) is an assembly consisting of a roller and stud used to effect a rolling contact with a cam, and convert the reciprocating or oscillating motion to linear motion.

Question 57

What is an Airframe Ball Bearing?

Accepted Answer

An Airframe Ball Bearing (BEARING,BALL,AIRFRAME) is a cylindrical item in which the inner or outer ring turns upon row(s) of hardened BALL, BEARING which roll on a raceway, thus minimizing friction. These items are characterized by their noncorrosive qualities, lightness of weight, inch dimensions rather than metric, inner rings generally projecting beyond the faces of the outer ring, or a very narrow width inner ring having an outside diameter slightly larger than the bore diameter. Designed primarily for use in aircraft assemblies, such as control systems and surfaces of aircraft. Excludes BEARING, BALL, ANNULAR.

Question 58

What is a Fairlead Ball Bearing?

Accepted Answer

A Fairlead Ball Bearing (BEARING,BALL,FAIRLEAD) is a special single or multiple-row ball bearing, rigid or self-aligning, and constructed with a fairlead at one end.

Question 59

What is a Track Roller Ball Bearing?

Accepted Answer

A Track Roller Ball Bearing (BEARING,BALL,TRACK ROLLER) is an antifriction bearing having spherical rolling elements designed for use in a track roller assembly.

Question 60

What is an Airframe Roller Bearing?

Accepted Answer

An Airframe Roller Bearing (BEARING,ROLLER,AIRFRAME) is a cylindrical item in which the inner or outer ring turns upon row(s) of hardened ROLLER, BEARING which roll on a raceway, thus minimizing friction. These items are characterized by their noncorrosive qualities, lightness of weight, inch dimensions rather than metric, inner rings generally projecting beyond the faces of the outer ring, or a very narrow width inner ring having an outside diameter slightly larger than the bore diameter. Designed primarily for use in aircraft assemblies, such as control systems and surfaces of aircraft. Excludes BEARING, ROLLER, CYLINDRICAL.

Question 61

What is a Track Roller Roller Bearing?

Accepted Answer

A Track Roller Roller Bearing (BEARING,ROLLER,TRACK ROLLER) is an antifriction bearing having cylindrical rolling elements designed for use in a track roller assembly.

Question 62

What is a Bell Crank Ball Bearing?

Accepted Answer

A Bell Crank Ball Bearing (BEARING,BALL,BELL CRANK) is a special double row ball bearing, retainer type, with integral flange.

Question 63

What is a Rod End Ball Bearing?

Accepted Answer

A Rod End Ball Bearing (BEARING,BALL,ROD END) is a special single or multiple-row ball bearing, rigid or self-aligning, and constructed with either a solid or hollow shank, internally or externally threaded.

Question 64

What is a Rod End Roller Bearing?

Accepted Answer

A Rod End Roller Bearing (BEARING,ROLLER,ROD END) is a special single or multiple-row roller bearing, rigid or self-aligning, and constructed with either inside threaded, plain hollow, maile threaded, or solid shank.

Bearings

Federal Supply Group (FSG): 31

NATO Supply Classification Group (NSG): 31

NSN Format for Bearings

Additional Information for Bearings

Bearings, Plain, Unmounted

Bearings, Mounted

Bearings, Antifriction, Unmounted

Frequently Asked Questions (FAQ) for Federal Supply Group 31

Top 20 Supply Items Included in Federal Supply Group 31

Stock Items for FSG 31 Page 69 of 1180