hantu guli a.k.a ball bearing

wan_fizah

salam....sya nk tanya pendapat terutama nyer otai2 civil engineering pasal ball bearing...member sya tnya knaper rumah dia mlm2 ader bunyi rolling2 mcm guli...sb tu dia pgil hantu guli...sounds stupido lak if i ckp hantu masa bln pose nih..hehehe...dia tnya uncle google n kuar ler xplaination cam nih....~explanation which i'd rather believe is this....semasa bangunan tu dibina, ball bearing diletakkan pada lantai dan dinding...ni kira nak bagi balance sbb kenkadang tapak tanah yg dibangunkan tu akan soften dan bangunan boleh tenggelam sedikit demi sedikit. ball bearing ni kira sbg balancing act supaya bangunan tak roboh terus. besi selalunya akan mengecut bila waktu sejuk....so ball bearings ni akan 'berlari' ke arah curam bangunan tu. i think it makes sense but maybe anyone here who's in the construction industry can support or repel this logic?~

chewan

Types of Bearings        
There are many types of bearings, each used for different purposes. These include ball bearings, roller bearings, ball thrust bearings, roller thrust bearings and tapered roller thrust bearings.


Ball Bearings

Ball bearings, as shown below, are probably the most common type of bearing. They are found in everything from inline skates to hard drives. These bearings can handle both radial and thrust loads, and are usually found in applications where the load is relatively small.

Photo courtesy The Timken Company Cutaway view of a ball bearing

In a ball bearing, the load is transmitted from the outer race to the ball, and from the ball to the inner race. Since the ball is a sphere, it only contacts the inner and outer race at a very small point, which helps it spin very smoothly. But it also means that there is not very much contact area holding that load, so if the bearing is overloaded, the balls can deform or squish, ruining the bearing.


Roller Bearings

Roller bearings like the one illustrated below are used in applications like conveyer belt rollers, where they must hold heavy radial loads. In these bearings, the roller is a cylinder, so the contact between the inner and outer race is not a point but a line. This spreads the load out over a larger area, allowing the bearing to handle much greater loads than a ball bearing. However, this type of bearing is not designed to handle much thrust loading.


A variation of this type of bearing, called a needle bearing, uses cylinders with a very small diameter. This allows the bearing to fit into tight places.

Photo courtesy The Timken Company Cutaway view of a roller bearing

Ball Thrust Bearing
Ball thrust bearings like the one shown below are mostly used for low-speed applications and cannot handle much radial load. Barstools and Lazy Susan turntables use this type of bearing.

Photo courtesy The Timken Company Ball thrust bearing

Roller Thrust Bearing
Roller thrust bearings like the one illustrated below can support large thrust loads. They are often found in gearsets like car transmissions between gears, and between the housing and the rotating shafts. The helical gears used in most transmissions have angled teeth -- this causes a thrust load that must be supported by a bearing.

Photo courtesy The Timken Company Roller thrust bearing

Tapered Roller Bearings
Tapered roller bearings can support large radial and large thrust loads.

Photo courtesy The Timken Company Cutaway view of (left) a spherical roller thrust bearing and (right) a radial tapered roller bearing

Tapered roller bearings are used in car hubs, where they are usually mounted in pairs facing opposite directions so that they can handle thrust in both directions.


mungkin ini sedikit membantu......

sumber : http://science.howstuffworks.com/

animaniac

salam....sya nk tanya pendapat terutama nyer otai2 civil engineering pasal ball bearing...member sya ...
wan_fizah Post at 26-8-2010 02:25

hello ! ini rasanya dah masuk dalam bab earthquake engineering , i tak arif benda ni.. setakat bagi link boley lerr  

http://www.bearingstrade.com/articles/bearings-applications.html

wan_fizah

thank u to chewan n animaniac...tp ader gak my boss ckp ball beraing kt mesia ni slalu guna for highway construction jer sb nk allow movement..n slalu for slab stability....kt mesia ni kita wat soil treatment jerr...misteri nusantara tul umah kawan i nihhh

penyapu

so ball bearings ni akan 'berlari' ke arah curam bangunan tu. i think it makes sense but maybe anyone here who's in the construction industry can support or repel this logic?~

dari pengalaman aku ball bearing ni kurangkan rotation pada sesuatu bangunan..mcm yang animaniac cakap..contoh bila gempa bumi ke..ada vibration..bila vibration mesti ada friction..jadi nak kurangkan letak ball bearing..contohnya bila dah design,masuk dead ngan live loads,dan jugak load luar macam angin dan lain-lain..ball bearing ni konsepnya nak bagi stabil dari bangunan tu tersenget belah kiri atau kanan..konsep struktur yg momenlentur daya ricih sume tu..biasanya untuk enapan,factor of safety akan diambil kira awal-awal untuk jangkamasa enapan tertentu depends pada foundation yang kita gunakan..ball bearing pun banyak guna kat kilang-kilang yg ada letak heavy machines..sebab nak tampung berat mesin tu..

wan_fizah

dari pengalaman aku ball bearing ni kurangkan rotation pada sesuatu bangunan..mcm yang animaniac ...
penyapu Post at 2-9-2010 11:39

thanks penyapu...very informatif...love u!!! x sabaq nk bgatau my fren...misteri nusantara dia

penyapu

terima kasih kedit dauws

tp ader gak my boss ckp ball beraing kt mesia ni slalu guna for highway construction jer sb nk allow movement..n slalu for slab stability....kt mesia ni kita wat soil treatment jerr...misteri nusantara tul umah kawan i nihhh

antara fungsi ball bearing adalah sebagai anti-seismic punya device..kira mcm anti-sway...highway construction pun ada ball bearing..sama mcm bridge structure dan flyover..tujuan dia nak untuk self-alignment gak..mcm bridge lak..kalu design,mesti amik kira gak setiap aspek bagi joints kat bridge..terutamanya expansion joints...dan bridge biasanya ada bridge bearing (konsep lebih kurang sama mcm ball bearing) yang fungsinya untuk agihkan beban atas bridge untuk dibawa ke foundation bawah...

kalu tengok kat mesia,ada beberapa jalan di mesia ni yang guna reinforce bar kat lapisan bawah dia..contohnya mcm kat highway di kawasan ayer keroh kalu tak silap aku..kalu ko lalu,ko akan rasa perbezaan bila drive dan bunyinya agak bising..dia tak sama mcm construction yang boh premix layer biasa tu....tu aku tak sure pakai ball-bearing ke tak sebab aku tak penah design jalan...kena tanya pakar jalan..

semoga dpt menjawab misteri kawan anda

wan_fizah

terima kasih kedit dauws



antara fungsi ball bearing adalah sebagai anti-seismic punya d ...
penyapu Post at 2-9-2010 20:10

best2 dpt reply frm otai eng...penyapu...u civil eng ekkk??? sila beri tunjuk ajar

penyapu

Reply 8# wan_fizah

no hal punya...bersamalah kita