Name: axial load support in pivot bearings
Uploaded: 2025-05-22T09:06:04.000Z
Duration: 1 min 23 s
Channel: JoVE

Rulman, makinelerdeki sürtünmeyi ve aşınmayı azaltırken iki parça arasında bağıl harekete izin veren mekanik bir elemandır.
Ayrıca radyal, eksenel veya her ikisinin bir kombinasyonu olabilen yüklerin dağıtılmasına da yardımcı olur.
Pivot rulmanlar, dönen bir şaft üzerindeki eksenel bir yükü destekler. Düz, konik veya kesik bir yüzeye sahip olabilirler.
Toplam yatak alanı πR2 olan eksenel bir yüke maruz kalan düz pivot bir rulman düşünün.
Yatak üzerindeki düzgün basınç, yükün yatak alanı üzerindeki oranı olarak ifade edilir.
Daha sonra, yatak alanı içinde sonsuz küçük bir yarıçap r ve kalınlık dr düşünün; halkaya iletilen yük tahmin edilebilir.
Şimdi, halkanın kaymasına direnen sürtünme kuvveti, r yarıçapında teğetsel olarak hareket eder.
Böylece, halkanın momentini hesaplayarak ve onu radyal sınırlar içine entegre ederek, sürtünme kuvvetlerinin üstesinden gelmek için gerekli olan milin momenti tahmin edilebilir.

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

pivot rulmanlar

Pivot Bearings

Mekanik sistemlerde, rulmanlar iki bileşen arasındaki göreceli hareketi kolaylaştırırken sürtünmeyi ve aşınmayı en aza indirmek için önemlidir. Makine parçaları üzerindeki çeşitli yükleri (radyal, eksenel veya her ikisinin kombinasyonu) dağıtarak düzgün ve verimli çalışmayı sağlarlar.

Bir pivot rulman, bir döner mil üzerindeki eksenel yükleri desteklemek için tasarlanmış özel bir rulman türüdür. Rulman yüzeyi veya pivot, eksenel itme kuvvetini desteklemek amacıyla milin sonunda konumlandırılır. Pivot, uygulamaya bağlı olarak düz, konik veya kısaltılmış bir yüzeye sahip olabilir.

Düz bir pivot rulmanda eksenel bir yüke maruz kaldığında, rulman üzerinde oluşan düzgün basınç, yükün rulman alanına oranı olarak hesaplanabilir. Bu basınç dağılımı, sürtünmeyi ve rulman yüzeyindeki aşınmayı en aza indirmeye yardımcı olarak daha verimli bir çalışma ve daha uzun bir servis ömrü sağlar.

Düz bir pivot rulmanda etkili olan kuvvetleri daha fazla analiz etmek için, rulman alanında bir sonsuz halkanın yarıçapı r ve kalınlığı dr olan bir halkayı inceleyebiliriz. Bu halkaya iletilen yük, rulman yüzeyi boyunca basınç dağılımına dayalı olarak tahmin edilebilir.

Mil döndükçe, sürtünme kuvvetleri halkanın kaymasına karşı direnir ve moment olarak r olarak tangele hareket eder. Halkanın momentini hesaplayarak ve radyal sınırlar içinde entegre ederek, miliş moment aşağıdaki gibi belirlenebilir:

<img alt="Equation 1" src="/files/ftp_upload/14324/14324_Equation_1v2.svg" style="text-align: center; height: 28px;" />

Denklem 1

Bu hesaplama, değişen yük koşulları altında rulmanın performansı ve verimliliği hakkında değerli bilgiler sağlar.

Pivot rulmanlar, dönen millerde eksel yükleri destekleme yetenekleri nedeniyle çeşitli sektörlerde ve mekanik sistemlerde kullanılmaktadır. Bu çok yönlü bileşenler, türbinler, jeneratörler, pompalar ve direksiyon sistemleri gibi otomotiv bileşenleri gibi dönen makinelerde bulunabilir. Ayrıca, iniş takımları ve uçuş kontrol yüzeyleri de dahil olmak üzere, hava ve uzay uygulamalarında pivot rulmanlar kritik öneme sahiptir. Vinçler, vinçler ve konveyörler gibi endüstriyel ekipmanlar da verimli çalışma ve güvenilir performans için pivot rulmanlara güvenmektedir. Sonuç olarak, pivot rulmanların çeşitli sektörlerde yaygın olarak kullanılması, düzgün ve etkili mekanik sistemlerin korunmasında önemlerini vurgulamaktadır.

Pivot Rulmanlar

Mekanik sistemlerde rulmanlar, sürtünme ve aşınmayı en aza indirirken iki bileşen arasındaki bağıl hareketi kolaylaştırmada çok önemlidir. Yardım ediyorlar ...

Education

JoVE Core

Mechanical Engineering

Makine Mühendisliği

Unit 1

Ünite 1

Friction

Sürtünme

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

axial load support in pivot bearings

Pivot bearings support axial loads on a rotating shaft. A bearing helps two parts move relative to each other while reducing friction and wear. In this design, the pivot is placed at the end of the shaft to carry the axial thrust.

The pivot surface can be flat, conical, or truncated, depending on the application. In a flat pivot bearing, the axial load is spread over the bearing area. The pressure is uniform and can be found by dividing the load by the area.

To study the forces more closely, engineers can look at a tiny ring inside the bearing surface. This ring has a radius r and a small thickness dr. The load on the ring depends on the pressure across the bearing area.

As the shaft turns, friction acts on the ring and resists sliding. This force acts tangentially at radius r. By finding the moment of the ring and integrating across the radial limits, the moment of the shaft can be determined. This helps explain how the bearing performs under different load conditions.

Pivot bearings are used in many machines and industries. They appear in turbines, generators, pumps, steering systems, and transmission assemblies. They are also important in aerospace parts such as landing gear and flight control surfaces, as well as in cranes, winches, and conveyors.

Axial Load Support in Pivot Bearings

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pivot bearings

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key terms and concepts

Learn how pivot bearings support axial loads on rotating shafts, reduce friction, and appear in turbines, generators, pumps, cars, aircraft, and industrial equipment.

Axial Load Support in Pivot 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

Axial Load Support in Pivot Bearings

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