Name: friction torque in collar bearings
Uploaded: 2023-09-22T11:49:30.000Z
Duration: 1 min 23 s
Channel: JoVE

Yakalı rulmanlar, makinelerde dönen miller üzerindeki eksenel yükleri desteklemek için kullanılan bir rulman türüdür, tek veya çok yakalı olabilir.
Eksenel bir yüke maruz kalan tek yakalı bir rulman düşünün. Bileziğin dış ve iç yarıçapı arasındaki alan, toplam yatak temas alanıdır.
Rulman için eşit destek varsayarsak, düzgün normal basınç, yatak alanı üzerindeki kuvvetin oranı olarak ifade edilebilir.
Rulman üzerinde sonsuz küçük bir alan elemanı düşünün. Diferansiyel alana etki eden kuvvet, sürtünme katsayısı, basınç ve diferansiyel alanın bir ürünü olarak ifade edilebilir.
Milin yaklaşmakta olan dönüşüne neden olmak için gereken moment, dönme ekseni etrafındaki moment denge denkleminden belirlenir.
Daha sonra, tüm sürtünme kuvvetlerinin üstesinden gelmek için gereken uygulanan momenti belirlemek için entegrasyon kullanılır.
Son olarak, diferansiyel kuvvet ve diferansiyel alan değerlerini değiştirerek ve denklemi toplam yatak alanı üzerine entegre ederek, şaftın momenti tahmin edilebilir.

<ol>
	<li>Hibbeler, R.C. (2016). Mühendislik Mekaniği \u2012 Statik ve Dinamik. Hoboken, New Jersey: Pearson Prentice Salonu. Sayfa 447-448.</li>
</ol>

yaka rulmanlar

Yaka rulmanlar, dönen miller üzerinde aksiyel yükleri desteklemek için tasarlanmış çeşitli makinelerde önemlidir. Belirli uygulama ve gereksinimlere bağlı olarak tek veya çoklu yakalarla bulunabilirler.

<img alt="Figure 1" src="/files/ftp_upload/14325/14325_Figure_1v3.svg" style="text-align: center; height: 300px;" />

Tek bir yaka yüküne maruz kalan bir yaka rulmanı düşünün. Toplam rulman temas alanı, yakanın dış yarıçapı ve iç yarıçapı arasındaki bölgedir. Rulmanın hatta destek sağladığı varsayıldığında, tekilleştirilmiş normal basınç, yaka üzerine uygulanan kuvvetin toplam temas alanına bölünmesiyle hesaplanabilir. Bu değer, rulman yüzeyi boyunca ortalama basınç dağılımını temsil eder.

Yaka rulmanı üzerinde etki eden kuvvetleri daha da analiz etmek için, rulman yüzeyindeki küçük bir sonsuz küçük alan elemanını düşünün. Bu sonsuz küçük alana etki eden kuvvet, sürtünme katsayısı, basınç ve diferansiyel alana bağlı bir çarpımdır. Bu değişkenler arasındaki ilişkiyi anlamak, milin dönmesi için gereken momentin hesaplanmasında önemlidir.

Mildenin yaklaşan dönmesi, dönme ekseni etrafındaki moment denge denklemi analiz edilerek belirlenir. Bu denklem, yakalı rulman tarafından oluşturulan sürtünme kuvvetleri de dahil olmak üzere mil üzerinde etkili olan tüm kuvvetleri ve momentleri dikkate alır.

<img alt="Equation 1" src="/files/ftp_upload/14325/14325_Equation_1v2.svg" style="text-align: center; height: 39px;" />

Bu denklemi entegre ederek, tüm bu sürtünme kuvvetlerini aşacak şekilde uygulanan moment belirlenebilir ve milin dönmesini başlatır. Son olarak, milin momentini tahmin etmek için diferansiyel kuvvet ve alan değerlerini entegre denklemine yerleştirin.

<img alt="Equation 2" src="/files/ftp_upload/14325/14325_Equation_2v2.svg" style="text-align: center; height: 55px;" />

Bu denklemi toplam rulman alanı üzerine entegre ederek, yakalı rulman üzerinde etkilenen kuvvet ve momentlerin ve milin dönmesi için gereken momentin kapsamlı bir anlayışı elde edilebilir.

<img alt="Equation 3" src="/files/ftp_upload/14325/14325_Equation_3v2.svg" style="text-align: center; height: 39px;" />

Yaka Rulmanlar

Yaka yatakları, dönen miller üzerindeki eksenel yükleri desteklemek için tasarlanmış çeşitli makinelerde gereklidir. Özel uygulamaya bağlı olarak ve ...

Education

JoVE Core

Mechanical Engineering

Makine Mühendisliği

Unit 1

Ünite 1

Friction

Sürtünme

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

Collar Bearings

friction torque in collar bearings

Collar bearings support axial loads on rotating shafts, and their friction helps determine the torque needed to start motion. They are used in many machines and may have a single collar or multiple collars, depending on the application and load needs.

For a single collar bearing under an axial load, the contact area is the ring-shaped region between the external radius and the internal radius of the collar. If the bearing is assumed to support the load evenly, the uniform normal pressure is found by dividing the applied force by this total bearing contact area. This gives the average pressure across the bearing surface.

To study the forces more closely, a small infinitesimal area element is considered on the collar surface. The force on that tiny area equals the friction coefficient times the pressure times the differential area. Using this relationship is important for finding the moment required to rotate the shaft.

The impending rotation of the shaft is found by writing the moment equilibrium equation about the rotational axis. This equation includes the forces and moments on the shaft, along with the frictional forces from the collar bearing. When the equation is integrated over the full bearing area, the applied moment needed to overcome friction and begin rotation can be determined.

Friction Torque in Collar Bearings

dry friction

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collar bearings

Collar bearings support axial loads on rotating shafts, and their friction helps determine the torque needed to start motion. They are used in many machines and may have a single collar or multiple collars, depending on the application and load needs. For a single collar bearing under an axial load, the contact area is the ring-shaped region between the external radius and the internal radius of the collar. If the bearing is assumed to support the load evenly, the uniform normal pressure is...

journal bearings

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key terms and concepts

Learn how collar bearing contact area, pressure, and friction work together to set the torque needed to start shaft rotation in mechanical systems.

Friction Torque in Collar Bearings | JoVE K12

JoVE Core Makine Mühendisliği, denge, kuvvetler, kafes kiriş analizi ve yapısal mekanik gibi temel konuları kapsayan kısa, anlaşılması kolay animasyonlu videolar sunar. Gerçek dünyadaki uygulamalarını keşfedin ve bilim insanlarının önderlik ettiği deneylerle bu kavramların uygulanmasına tanık olun.

mechanical engineering

Friction Torque in Collar Bearings

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