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Kopling Dari Wikipedia bahasa Indonesia, ensiklopedia bebas Belum Diperiksa Kopling dua buah poros yang berputar Tujuan utama dari kopling adalah menyatukan dua bagian yang dapat berputar. Dengan pemilihan, pemasangan, dan perawatan yang teliti, performa kopling bisa maksimal, kehilangan daya bisa minimum, dan biaya perawatan bisa diperkecil. Daftar isi 1 Manfaat 2 Jenis Kopling o 2.1 Kopling Kaku o 2.2 Kopling fleksibel 3 Pranala luar Manfaat Kopling digunakan dalam permesinan untuk berbagai tujuan: Untuk menghubungkan dua unit poros yang dibuat secara terpisah, seperti poros motor dengan roda atau poros generator dengan mesin. Kopling mampu memisahkan dan menyambung dua poros untuk kebutuhan perbaikan dan penggantian komponen. Untuk mendapatkan fleksibilitas mekanis, terutama pada dua poros yang tidak berada pada satu aksis. Untuk mengurangi beban kejut ( shock load ) dari satu poros ke poros yang lain. Untuk menghindari beban kerja berlebih. Untuk mengurangi karakteristik getaran dari dua poros yang berputar. Jenis Kopling Kopling Kaku Kopling kaku adalah unit kopling yang menyatukan dua jenis poros yang tidak mengizinkan terjadinya perubahan posisi kedua poros atau terlepas, disengaja atau tidak disengaja, ketika beroperasi. Kopling kaku merupakan pilihan yang tepat ketika kedua poros ingin dihubungkan dengan pengaturan posisi yang stabil dan presisi. Kopling ini merupakan
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Page 1: Dial indikator

Kopling

Dari Wikipedia bahasa Indonesia, ensiklopedia bebas

Belum Diperiksa

Kopling dua buah poros yang berputar

Tujuan utama dari kopling adalah menyatukan dua bagian yang dapat berputar. Dengan

pemilihan, pemasangan, dan perawatan yang teliti, performa kopling bisa maksimal,

kehilangan daya bisa minimum, dan biaya perawatan bisa diperkecil.

Daftar isi

1 Manfaat

2 Jenis Kopling

o 2.1 Kopling Kaku

o 2.2 Kopling fleksibel

3 Pranala luar

Manfaat

Kopling digunakan dalam permesinan untuk berbagai tujuan:

Untuk menghubungkan dua unit poros yang dibuat secara terpisah, seperti poros

motor dengan roda atau poros generator dengan mesin. Kopling mampu memisahkan

dan menyambung dua poros untuk kebutuhan perbaikan dan penggantian komponen.

Untuk mendapatkan fleksibilitas mekanis, terutama pada dua poros yang tidak berada

pada satu aksis.

Untuk mengurangi beban kejut ( shock load ) dari satu poros ke poros yang lain.

Untuk menghindari beban kerja berlebih.

Untuk mengurangi karakteristik getaran dari dua poros yang berputar.

Jenis Kopling

Kopling Kaku

Kopling kaku adalah unit kopling yang menyatukan dua jenis poros yang tidak mengizinkan

terjadinya perubahan posisi kedua poros atau terlepas, disengaja atau tidak disengaja, ketika

beroperasi. Kopling kaku merupakan pilihan yang tepat ketika kedua poros ingin

dihubungkan dengan pengaturan posisi yang stabil dan presisi. Kopling ini merupakan

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kopling dengan usia pakai yang paling tinggi selama batasan torsi, RPM, dan beban dari

poros dan kopling tidak dilampaui.

Kopling fleksibel

Kopling beam dengan bagian ulir heliksnya

Rzeppa joint dan...

... Double Cardan Joint yang merupakan contoh dari kopling CV

Kopling roda gigi

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Kopling Oldham

Universal joint

Kopling fleksibel digunakan ketika kedua poros ada sedikit perubahan posisi secara aksial,

radial, maupun angular ketika mesin beroperasi. Beberapa jenis kopling fleksibel yaitu:

Beam

Kopling CV (constant-velocity)

Diafragma

Disc coupling

Fluid coupling

Kopling roda gigi (gear coupling)

Hirth joint

Oldham

Rag joint

Universal joint

Kopling beam, atau bisa juga disebut dengan kopling heliks, adalah kopling yang

menghantarkan daya antara dua poros dengan memperbolehkan adanya perubahan posisi dari

poros secara angular, aksial, maupun paralel hingga batasan tertentu, ketika poros bekerja.

Desain dari kopling beam adalah sepotong kopling yang memiliki bagian yang kosong

sepanjang badan kopling berbentuk heliks atau spiral, sehingga menjadikannya fleksibel.

Kopling beam biasanya dibuat dari logam paduan aluminium, baja tahan karat, dan titanium.

Gear coupling adalah kopling yang mentransmisikan daya antara dua poros yang tidak berada

dalam satu garis. Kedua poros dihubungkan dengan poros ketiga di dalam kopling yang

disebut sebagai spindle.

Kopling CV adalah kopling yang memungkinkan untuk mentransmisikan daya pada sudut

yang bervariasi dan pada kecepatan putar yang konstan. Kopling jenis ini biasa digunakan

pada mobil front wheel drive dan all wheel drive.

Universal joint adalah jenis kopling dalam bentuk dua batangan kaku yang memungkinkan

terjadinya pembelokan arah transmisi daya dari sumber daya. Uniersal joint terdiri dari

sepasang hinge yang berdekatan dan dihubungkan dengan cross shaft. Universal joint, walau

dapat mentransmisikan daya yang tidak segaris, namun memiliki kekurangan, yaitu dapat

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memberikan output RPM yang tidak konstan walau input RPM konstan. Hal itu bisa

menyebabkan getaran dan keausan pada komponen mesin.

Pranala luar

Wikimedia Commons memiliki kategori mengenai Kopling

Wikidata: Clutches

Shaft Coupling Glossary

List of coupling types

Flash Animation of Oldham coupler

Biography of Oldham at Cornell University

Animation Video of a shaft coupling

Yutaka Nishiyama, From Oldham's Coupling to Air Conditioners

A coupling is a device used to connect two shafts together at their ends for the purpose of

transmitting power. Couplings do not normally allow disconnection of shafts during

operation, however there are torque limiting couplings which can slip or disconnect when

some torque limit is exceeded.

The primary purpose of couplings is to join two pieces of rotating equipment while

permitting some degree of misalignment or end movement or both. By careful selection,

installation and maintenance of couplings, substantial savings can be made in reduced

maintenance costs and downtime.

Contents

1 Uses 2 Types

o 2.1 Rigid 2.1.1 Sleeve coupling 2.1.2 Flange coupling 2.1.3 Clamp or split-muff coupling 2.1.4 Tapered shaft lock 2.1.5 Hirth

o 2.2 Flexible 2.2.1 Bush pin Type flange coupling 2.2.2 Beam 2.2.3 Constant velocity 2.2.4 Diaphragm 2.2.5 Disc 2.2.6 Fluid 2.2.7 Gear 2.2.8 Oldham

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2.2.9 Rag joint 2.2.10 Universal joint 2.2.11 Others

3 Requirements of good shaft alignment / good coupling setup 4 Coupling maintenance and failure 5 Checking the coupling balance 6 See also 7 References 8 External links

Uses

Shaft couplings are used in machinery for several purposes. The most common of which are

the following.[1]

To provide for the connection of shafts of units that are manufactured separately such as a motor and generator and to provide for disconnection for repairs or alterations.

To provide for misalignment of the shafts or to introduce mechanical flexibility. To reduce the transmission of shock loads from one shaft to another. To introduce protection against overloads. To alter the vibration characteristics of rotating units. To connect driving and the driven part

Types

Rigid

A rigid coupling is a unit of hardware used to join two shafts within a motor or mechanical

system. It may be used to connect two separate systems, such as a motor and a generator, or

to repair a connection within a single system. A rigid coupling may also be added between

shafts to reduce shock and wear at the point where the shafts meet.

When joining shafts within a machine, mechanics can choose between flexible and rigid

couplings. While flexible units offer some movement and give between the shafts, rigid

couplings are the most effective choice for precise alignment and secure hold. By precisely

aligning the two shafts and holding them firmly in place, rigid couplings help to maximize

performance and increase the expected life of the machine. These rigid couplings are

available in two basic designs to fit the needs of different applications. Sleeve-style couplings

are the most affordable and easiest to use. They consist of a single tube of material with an

inner diameter that's equal in size to the shafts. The sleeve slips over the shafts so they meet

in the middle of the coupling. A series of set screws can be tightened so they touch the top of

each shaft and hold them in place without passing all the way through the coupling.

Clamped or compression rigid couplings come in two parts and fit together around the shafts

to form a sleeve. They offer more flexibility than sleeved models, and can be used on shafts

that are fixed in place. They generally are large enough so that screws can pass all the way

through the coupling and into the second half to ensure a secure hold.Flanged rigid couplings

are designed for heavy loads or industrial equipment. They consist of short sleeves

surrounded by a perpendicular flange. One coupling is placed on each shaft so the two

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flanges line up face to face. A series of screws or bolts can then be installed in the flanges to

hold them together. Because of their size and durability, flanged units can be used to bring

shafts into alignment before they are joined together. Rigid couplings are used when precise

shaft alignment is required; shaft misalignment will affect the coupling's performance as well

as its life. Examples:

Sleeve coupling

A sleeve coupling consists of a pipe whose bore is finished to the required tolerance based on

the shaft size. Based on the usage of the coupling a keyway is made in the bore in order to

transmit the torque by means of the key. Two threaded holes are provided in order to lock the

coupling in position.

Sleeve couplings are also known as Box Couplings. In this case shaft ends are coupled

together and abutted against each other which are enveloped by muff or sleeve. A gib head

sunk keys hold the two shafts and sleeve together. in other words, this is the simplest type of

the coupling. It is made from the cast iron and very simple to design and manufacture. It

consists of a hollow pipe whose inner diameter is same as diameter of the shafts. The hollow

pipe is fitted over a two or more ends of the shafts with the help of the taper sunk key.a key

and sleeve are useful to transmit power from one shaft to another shaft.

Flange coupling

This coupling has two separate cast iron flanges. Each flange is mounted on the shaft end and

keyed to it. The two flanges are coupled together with the help of bolts and nuts. The

projected portion of one of the flanges and corresponding recess on the other flange help to

bring the shaft into line and to maintain alignment. A flange which is provided with a shroud

which shelters the bolts heads and nuts is called protected type flange coupling.

Clamp or split-muff coupling

In this coupling, the muff or sleeve is made into two halves parts of the cast iron and they are

join together by means of mild steel studs or bolts. The advantages of this coupling is that

assembling or disassembling of the coupling is possible without change the position of the

shaft. This coupling is used for heavy power transmission at moderate speed.

Tapered shaft lock

A tapered lock is a form of keyless shaft locking device[2] that does not require any material

to be removed from the shaft. The basic idea is similar to a clamp coupling but the moment of

rotation is closer to the center of the shaft.[3] An alternative coupling device to the traditional

parallel key, the tapered lock removes the possibility of play due to worn keyways.[4][5][6] It is

more robust than using a key because maintenance only requires one tool and the self-

centering balanced rotation means it lasts longer than a keyed joint would, but the downside

is that it costs more.[citation needed]

Hirth

Main article: Hirth joint

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Hirth joints use tapered teeth on two shaft ends meshed together to transmit torque.

Flexible

Flexible couplings are used to transmit torque from one shaft to another when the two shafts

are slightly misaligned. Flexible couplings can accommodate varying degrees of

misalignment up to 3° and some parallel misalignment. In addition, they can also be used for

vibration damping or noise reduction.This coupling is used to protect the driving and driven

shaft members against harmful effects produce due to misalignment of the shafts, sudden

shock loads, shaft expansion or vibrations etc.

Bush pin Type flange coupling

This is used for slightly imperfect alignment of the two shafts.

This is modified form of the protected type flange coupling. This type of coupling has pins

and it works with coupling bolts. The rubber or leather bushes are used over the pins. The

coupling has two halves dissimilar in construction. The pins are rigidly fastened by nuts to

one of the flange and kept loose on the other flange. This coupling is used to connect of

shafts which having a small parallel misalignment, angular misalignment or axial

misalignment. In this coupling the rubber bushing absorbs shocks and vibration during its

operations. This type of coupling is mostly used to couple electric motors and machines.

Beam

A beam coupling

A beam coupling, also known as helical coupling, is a flexible coupling for transmitting

torque between two shafts while allowing for angular misalignment, parallel offset and even

axial motion, of one shaft relative to the other. This design utilizes a single piece of material

and becomes flexible by removal of material along a spiral path resulting in a curved flexible

beam of helical shape. Since it is made from a single piece of material, the Beam Style

coupling does not exhibit the backlash found in some multi-piece couplings. Another

advantage of being an all machined coupling is the possibility to incorporate features into the

final product while still keep the single piece integrity.

Changes to the lead of the helical beam provide changes to misalignment capabilities as well

as other performance characteristics such as torque capacity and torsional stiffness. It is even

possible to have multiple starts within the same helix.

The material used to manufacture the beam coupling also affects its performance and

suitability for specific applications such as food, medical and aerospace. Materials are

typically aluminum alloy and stainless steel, but they can also be made in acetal, maraging

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steel and titanium. The most common applications are attaching encoders to shafts and

motion control for robotics.

A beam coupling with optional features machined into it

Increasing number of coils allows for greater angular misalignment

Constant velocity

Main article: Constant-velocity joint

There are various types of constant-velocity (CV) couplings: Rzeppa joint, Double cardan

joint, and Thompson coupling.

Diaphragm

Diaphragm couplings transmit torque from the outside diameter of a flexible plate to the

inside diameter, across the spool or spacer piece, and then from inside to outside diameter.

The deforming of a plate or series of plates from I.D. to O.D accomplishes the misalignment.

Disc

Main article: Disc coupling

Disc couplings transmit torque from a driving to a driven bolt tangentially on a common bolt

circle. Torque is transmitted between the bolts through a series of thin, stainless steel discs

assembled in a pack. Misalignment is accomplished by deforming of the material between the

bolts.

Fluid

Main article: Fluid coupling

Gear

A gear coupling

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A gear coupling is a mechanical device for transmitting torque between two shafts that are

not collinear. It consists of a flexible joint fixed to each shaft. The two joints are connected

by a third shaft, called the spindle.

Each joint consists of a 1:1 gear ratio internal/external gear pair. The tooth flanks and outer

diameter of the external gear are crowned to allow for angular displacement between the two

gears. Mechanically, the gears are equivalent to rotating splines with modified profiles. They

are called gears because of the relatively large size of the teeth.

Gear couplings and universal joints are used in similar applications. Gear couplings have

higher torque densities than universal joints designed to fit a given space while universal

joints induce lower vibrations. The limit on torque density in universal joints is due to the

limited cross sections of the cross and yoke. The gear teeth in a gear coupling have high

backlash to allow for angular misalignment. The excess backlash can contribute to vibration.

Gear couplings are generally limited to angular misalignments, i.e., the angle of the spindle

relative to the axes of the connected shafts, of 4-5°. Universal joints are capable of higher

misalignments.

Single joint gear couplings are also used to connected two nominally coaxial shafts. In this

application the device is called a gear-type flexible, or flexible coupling. The single joint

allows for minor misalignments such as installation errors and changes in shaft alignment due

to operating conditions. These types of gear couplings are generally limited to angular

misalignments of 1/4-1/2°.

Oldham

Animated Oldham coupler

An Oldham coupling has three discs, one coupled to the input, one coupled to the output, and

a middle disc that is joined to the first two by tongue and groove. The tongue and groove on

one side is perpendicular to the tongue and groove on the other. The middle disc rotates

around its center at the same speed as the input and output shafts. Its center traces a circular

orbit, twice per rotation, around the midpoint between input and output shafts. Often springs

are used to reduce backlash of the mechanism. An advantage to this type of coupling, as

compared to two universal joints, is its compact size. The coupler is named for John Oldham

who invented it in Ireland, in 1821, to solve a paddle placement problem in a paddle steamer

design.

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Oldham coupler, assembled

Oldham coupler, disassembled

Rag joint

Main article: Rag joint

Rag joints are commonly used on automotive steering linkages and drive trains. When used

on a drive train they are sometimes known as giubos.

Universal joint

Main article: Universal joint

Others

Bellows coupling — low backlash Elastomeric coupling

o Bushed pin coupling o Donut coupling o Spider or jaw coupling (or Lovejoy® coupling)

Geislinger coupling Resilient coupling Roller chain and sprocket coupling Schmidt coupling

Requirements of good shaft alignment / good coupling

setup

Main article: Shaft alignment

It should be easy to connect or disconnect the coupling. It does allow some misalignment between the two adjacent shaft rotation axes. Its goal should be to minimise the remaining misalignment in running operation so as to

maximise power transmission and to maximise machine runtime (coupling, bearing and sealing's lifetime).

It should have no projecting parts.

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It is recommended to use manufacturer's alignment target values to set up the machine train to a defined non-zero alignment, due to the fact that later, when the machine is at operation temperature, the alignment condition is perfect

Coupling maintenance and failure

Coupling maintenance is generally a simple matter, requiring a regularly scheduled

inspection of each coupling. It consists of:

Performing visual inspections, checking for signs of wear or fatigue, and cleaning couplings regularly.

Checking and changing lubricant regularly if the coupling is lubricated. This maintenance is required annually for most couplings and more frequently for couplings in adverse environments or in demanding operating conditions.

Documenting the maintenance performed on each coupling, along with the date.[7]

Even with proper maintenance, however, couplings can fail. Underlying reasons for failure,

other than maintenance, include:

Improper installation Poor coupling selection Operation beyond design capabilities.[7]

The only way to improve coupling life is to understand what caused the failure and to correct

it prior to installing a new coupling. Some external signs that indicate potential coupling

failure include:

Abnormal noise, such as screeching, squealing or chattering Excessive vibration or wobble Failed seals indicated by lubricant leakage or contamination.[7]

Checking the coupling balance

Couplings are normally balanced at the factory prior to being shipped, but they occasionally

go out of balance in operation. Balancing can be difficult and expensive, and is normally

done only when operating tolerances are such that the effort and the expense are justified.

The amount of coupling unbalance that can be tolerated by any system is dictated by the

characteristics of the specific connected machines and can be determined by detailed analysis

or experience.[7]

See also

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The clutch is a device used to connect two shafts at both ends for the

purpose of transmitting mechanical power . Clutch usually does not allow

the separation between the two shafts when operating , but currently there

is a clutch that has a limited torque so it can slip or disconnect when the

torque limit is skipped.

The main purpose of the clutch is to unite the two parts which can rotate .

With the selection , installation , and maintenance of a thorough , clutch

performance to the maximum , minimum power loss can , and maintenance costs

would be minimized .

Couplings used in machinery for a variety of purposes :

• To connect two shaft units are made separately , such as the motor shaft

to the wheel with the engine or generator shaft . Clutch is able to

separate and connect two shafts for the repair and replacement parts needs

.

• For mechanical flexibility , especially on the two shafts that are not

located on one axis .

• To reduce the shock loads ( shock load ) from one shaft to another shaft

.

• To avoid excessive workload .

• To reduce the vibration characteristics of two rotating shafts .

Rigid couplings

Rigid coupling is the coupling unit which brings together two types of

shaft which does not allow a change in the position of the shaft or

released , intentionally or unintentionally , when in operation. Rigid

coupling is the right choice when the shaft wants to be associated with a

stable position control and precision . This clutch is a clutch with the

highest service life limits for torque, RPM , and the weight of the shaft

and the clutch is not exceeded.

Coupling beam , or it could be called a helix clutch , is a clutch that

delivers power between two shafts to allow for the change in angular

position of the shaft , axial , and parallel to a limited extent , when the

shaft work . The design of the coupling beam is a clutch that has the

blanks along the body of a helical or spiral -shaped clutch , making it

flexible . Coupling beam is usually made of aluminum alloy , stainless

steel , and titanium .

Gear coupling is a coupling that transmits power between two shafts that

are not in one line . The two shafts are connected by a third shaft inside

the clutch are referred to as the spindle .

CV clutch is a clutch that allows it to transmit power at varying angles

and at a constant rotational speed . This type of coupling used on front

wheel drive cars and all-wheel drive .

Universal joint coupling is in the form of two types of rigid rod that

allows the deflection direction of transmitting power from the power source

. Uniersal hinge joint consisting of a pair of adjacent and connected by a

cross shaft . Universal joint , though not transmit power line , but has a

drawback, which can provide an output RPM is not constant even though the

input constant RPM . It can cause vibration and wear on engine components .