Kaca Tempered (Tempered Glass)

Why Tempered Glass is Safety Glass

The brittle nature of tempered glass causes it to shatter into small oval-shaped pebbles when broken. This eliminates the danger of sharp edges. Due to this property — along with its strength — tempered glass is often referred to as ‘safety glass.’

The thermal process that cures tempered glass also makes it heat-resistant. Tempered glass can be used in any situation where there is a danger of the glass breaking due to impact or extreme heat.

Kenapa Kaca Tempered disebut Kaca Yang Aman (Safety Glass)

Kaca Tempered sering digunakan ketika Kaca Biasa dapat menimbulkan potensi yang membahayakan ketika diaplikasikan.  Kaca Tempered memiliki kekuatan 4-5 kali lebih kuat dari kaca biasa dan tidak hancur/ pecah dalam pecahan besar.

Kaca Tempered diproduksi melalui proses pemanasan yang ekstrem dan pendinginan secara mendadak di kedua sisinya.  Secara signifikan Kaca Tempered sangat kuat dibandingkan dengan Kaca Biasa.

Karakteristik dari Kaca Tempered adalah ketika pecah berbentuk kecil-kecil seperti butiran jagung dan tumpul pada ujung-ujungnya.  Sehingga mengurangi tingkat bahaya dari pecahannya yang tajam.  Karena sifat inilah Kaca Tempered disebut 'Safety Glass'.

Proses pemanasan membuat Kaca Tempered tahan panas juga.  Kaca Tempered dapat digunakan pada berbagai situasi, dimana ada bahaya ketika kaca pecah yang atau panas yang ekstrim.

Disini di Jakarta Glass Works, Kami memiliki kapasitas untuk mengerjakan Kaca Tempered dengan berbagai ketebalan dan ukuran.

Apa yang dimaksud dengan Kaca Tempered (Tempered Glass)?

Kaca Tempered adalah kaca yang sangat kuat yang mengalami proses pemanasan sehingga menyebabkan kompresi tekanan di level 11000-20000 psi pada permukaan kacanya dan kompresi pada tepi kaca tidak lebih dari 9700 psi. 

Kaca yang sudah masuk mesin tempered tidak dapat dipotong, diubah, digosok bagian tepinya, dilobangi, dicowak, dll.  Semua proses itu dapat dilakukan sebelum kaca masuk ke dalam mesin tempered.

Process

Trutuf tempered glass is made on state-of-the-art, electrically heated horizontal furnaces, which heat the glass to an uniform temperature of approximately 700ºC. Ceramic rollers convey the glass through the furnace at speeds regulated to ensure temperature uniformity and minimal optical distortions. When the glass exits from the furnace, it is rapidly cooled by a series of air nozzles. This rapid cooling puts the glass surface into a state of compression, with the center core in tension. In the final stress distribution, the sum of the forces in compression equals the forces in tension.

Trutuf kaca tempered dibuat sebagai satu kesatuan, dimana aliran listrik mengalir pada tungku horisontal, yang memanaskan kaca pada suhu seragam 700 ° C.    Silider (rol) keramik memdorong kaca masuk ke dalam tungku panas pada kecepatan yang telah diatur untuk memastikan keseragaman suhu dan meminimalisirkan distorsi pada kaca.   Ketika kaca keluar dari tungku pemanasan, dengan segera didinginkan oleh serangkaian nozel/ pipa yang mengeluarkan angin pada kedua sisi kaca.   Proses pendinginan yang tiba-tiba ini menjadikan permukaan kaca dalam keadaan kompresi (termampatkan), dimana inti pusat kaca dalam keadaan tegang.   Pada akhir pendistribusian tekanan pada kaca, jumlah yang dimampatkan sama dengan pada tekanannya.

Tempered glass gains its added strength from these compressed surfaces. However, if the surface is penetrated by a scratch or an impact, the glass will break into a number of small particles. The heat treatment process for toughening glass requires that all fabrication be completed prior to toughening. Any attempt to cut, drill, grind or sand blast the glass after toughening may result in glass breakage. The surface hardness is not changed by the heat treatment process. The glass surface after heat treatment will have the same resistance to surface damage as annealed glass. Tempering process does not change in any way the light transmission and solar radiant heat properties of glass.

Kaca Tempered bertambah kuat karena permukaan kaca yang terkompresikan (termampatkan).  Namun, jika permukaan kaca tersebut terdapat penetrasi goresan (scratch) yang dalam, maka sewaktu-waktu kaca tersebut dapat pecah menjadi pecahan kecil-kecil (yang disebut pecahan jagung).   Semua proses untuk membuat Kaca Tempered harus dilakukan terlebih dahulu sebelum kaca dipanaskan.   Semua percobaan untuk memotong, melubangi, menggosok, ataupun sandblast ketika kaca sudah dipanaskan akan menyebabkan kaca tersebut pecah.   Permukaan kaca yang keras itu membuat kaca tidak dapat diproses lagi.   Permukaan kaca yang telah melewati proses pemanasan akan menghambat kerusakan kaca, tidak seperti kaca biasa.

Characteristics

• High Thermal Shock Strength : Can with stand temperature differentials upto 250ºC.
• Safety : Tempered Glass is very difficult to break but even on
  breakage, it will break into small, relatively harmless fragments. This
  substantially reduces the likelihood of injury to people as there are no
  jagged edges or sharp corners which are normal in the case of
  breakage of annealed glass. Due to the inherent superior features of
  Tempered Glass, like more strength, ability to withstand sudden impacts and breaking into small pieces, it is
  considered as a safety glazing and so in most countries, use of Architectural Toughened Glass is mandatory for
  entrances in public areas or where it is to be used by general public.
• Light and Heat transmission properties : Do not change due to tempering and remain the same as in unprocessed glass unless laminated or double glazed.
• Alterations : Tempered glass cannot be further cut,  ground, drilled or worked upon. All these processes are completed prior to its tempering, in accordance with the drawings, sizes or templates.
• Strength : Toughened (or Tempered Glass) is four to five times stronger
  than its equivalent thickness of normal annealed float or sheet glass.
• Others : The Tempering process on normal glass does not alter the light transmission and solar radiant heat
  properties of the glass. Tempered glass cannot be further cut, ground, drilled or worked upon. Tempered Glass
  is prepared by completing prior to its tempering, all such works in accordance with drawings, sizes or
  templates.

All applications, where strength and safety are the key requirements like -

• Curtain walls and structural glazing
• Bolted structural glazing
• Doors and Partitions
• Large windows
• Shower installations
• Squash courts
• Furniture
• Automobiles and Railways
• Kitchen appliances
• Lighting fixtures
• Ships and boats
• Fire knockout windows
• Solar Panels
• Fireplace Screens

Precautions

• Alteration : Tempered glass cannot be cut or drilled after tempering. Any field alterations, including edge grinding, sand blasting or acid etching can cause premature failure.
• Strain Pattern : A common characteristics of all tempered glass is a strain pattern sometimes referred to as “iridescence”. This strain pattern is visible under certain lighting conditions and when the tempered glass is viewed at sharp angles. The strain pattern is inherent in the tempering process and is not considered a defect.
• Spontaneous Breakage : Tempered glass is more prone to spontaneous breakage than annealed or heat strengthened glass. Spontaneous breakage can result from impact damage, weld splatter, windblown debris and internal inclusions.
• Distortions : As can be expected with any heat treated glass, bow, warp and roller waves are inherent characteristics of the tempering process. These are maintained and guaranteed to be within the limits set by ASTM Standard C-1048 or DIN 1249
• Critical Applications : Tempered glass as monolithic or single glass should not be used for certain critical applications like - overhead glazing or railings with risk of fall.
  

Availability

Tempered glass (also known as toughened glass) is an extremely strong
glass which has been thermally heat treated to induce compressive
stresses of 10,000 to 20,000 psi on the surfaces and edge compression of
not less than 9700 psi.
Tempered glass is being used increasingly in architecture because of its
strength and safety properties. It is usually installed in areas where
safety glass is required to reduce the possibility of mechanical or
thermal breakage and/ or to assure greater uniform load strength.
Worldwide the use of Tempered glass or Safety glass in general has
been mandated by building codes. These codes are also made for India
and are in the process of being mandated.
Cut to size glass sheets are electrically heated in the furnace where it
oscillates back and forth on rollers till glass reaches temperature of about
650°C. After heating, the glass is conveyed to a quenching chamber
where it is cooled rapidly by a blast of air, blown through nozzles, on
both sides of the glass.