Sedikit latar belakang bagaimana besi beton dibuat
Besi beton diproduksi secara umum terdiri dari 3 jenis: besi beton permukaan polos (round bar), besi beton ulir (deformed bar) dan besi beton kanal u (shape). Bahan baku besi beton adalah billet, yang juga merupakan balok baja berukuran 100 x 100 mm, 110 x 110 mm, 120 x 120mm dengan panjang masing-masing sekitar 170 mm. Bahan baku dari billet sendiri adalah besi-besi tua, skrap, serta bahan penolong seperti kokas, grafit, lime, ferro alloys yang dilebur dengan berbagai metode. Bahan penolong tadi digunakan untuk mendapatkan unsur carbon (C), Si (silicon), Mn (Mangan) yang akan sangat berpengaruh pada qualitas besi beton.
Mutu besi beton yang baik adalah yang telah memiliki kekuatan tarik (standard yield strength / Ys) minimal 24 kg / mm2. Kadar carbon berpengaruh besar kepada sifat mekanik dari besi beton. Kadar carbon yang terlalu besar akan membuat besi beton menjadi lebih getas dan akan meningkatkan kekerasan dan kekuatan tarik tetapi keuletannya cenderung menurun. Kadar unsur silikon berpengaruh terhadap struktur mikro besi beton. Kadar silikon yang rendah mengakibatkan besi menjadi kropos. Kadar unsur mangan berpengaruh besar pada keuletan besi beton. Unsur mangan yang terlalu banyak dapat meningkatkan keuletan tetapi mengurangi kekerasan.
Cara menghitung berat besi beton SNI (Standard Nasional Indonesia)
Polos dengan grade U24 (Standard Yield Strength: 24 kg / mm2)
Ulir dengan grade U40 (Standard Yield Strength: 40 kg / mm2)
Berat (dalam kg) = diameter (mm) * diameter (mm) * panjang (m) * 0.006165
0.006165 merupakan coefisien dalam mencari berat besi beton.
Sebagai contoh besi dengan diameter 10mm dan panjang 12m mempunyai berat
10*10*12*0.006165 = 7.398 kg
Untuk daerah bali dan sekitarnya, besi yang banyak dipasarkan adalah besi dari PT Hanil Jaya Steel - Surabaya. Hal ini dikarenakan biaya transportasi yang lebih murah dan kualitas besi beton yang baik. Besi beton SNI dari pabrik Hanil mempunyai toleransi 0.2mm dengan panjang 12m. Besi beton jenis ini mempunyai marking seperti "HIJ SNI 16mm" untuk ukuran 16mm.
Besi Beton Ulir/Sirip SNI 13mm
Besi Beton Polos SNI 10mm
Contoh diatas adalah besi beton ulir SNI 13mm (S13 = Sirip 13) dan besi beton polos SNI 10mm (P10 = Polos 10)
Selain besi beton jenis SNI, terdapat juga besi beton NON-SNI atau sering kali disebut BANCI. Kekuatan tarikan atau yield strength dari besi beton jenis ini tidak dapat dipastikan. Untuk besi beton dengan marking HJ menurut informasi dari pabrik mempunyai kekuatan U19-20 untuk yang jenis polos dan untuk jenis ulir mempunya kekuatan U25-30. Toleransi untuk besi beton jenis ini biasanya lebih besar sampai 0.3mm dengan panjang 12m dan terdapat marking dengan berbagai tanda salah satunya HJ.
Besi Beton NON SNI Ulir/Sirip 13mm
Besi Beton NON SNI Ulir/Sirip 13mm (Ukuran Sket 12.5mm)
Terdapat lagi jenis besi beton tarikan. Besi beton jenis ini biasanya tidak mempunyai panjang 12m dan tidak terdapat marking atau tanda.
Terdapat fenomena belakangan ini banyak penjual menjual kawat baja dan bukan besi beton. Besi beton dengan diameter ukuran 6-10mm yang sering kali menjadi korban. Fungsi dari kawat baja sangat berbeda dengan besi beton. Kawat baja berfungsi untuk pengikat dan besi beton berfungsi untuk penyangga. Sehingga kekuatan tarikan kawat baja jauh dibawah kekuatan besi beton. Hanya saja diameter kawat baja ini sama besar dengan besi beton ukuran tertentu. Hal ini sering kali digunakan untuk mendapatkan pasar atau pun mengeruk keuntungan maximal.
Anda dapat mempercayakan supplier besi anda kepada kami. Kami hanya menjual besi dari PT Hanil Jaya Steel - Surabaya dengan marking HIJ untuk besi beton SNI dan marking HJ untuk besi beton NON-SNI.
As Vice Moves More to TV, It Tries to Keep Brash Voice
The live music at the Vice Media party on Friday shook the room. Shane Smith, Vice’s chief executive, was standing near the stage — with a drink in his hand, pants sagging, tattoos showing — watching the rapper-cum-chef Action Bronson make pizzas.
The event was an after-party, a happy-hour bacchanal for the hundreds of guests who had come for Vice’s annual presentation to advertisers and agencies that afternoon, part of the annual frenzy for ad dollars called the Digital Content NewFronts. Mr. Smith had spoken there for all of five minutes before running a slam-bang highlight reel of the company’s shows that had titles like “Weediquette” and “Gaycation.”
In the last year, Vice has secured $500 million in financing and signed deals worth hundreds of millions of dollars with established media companies like HBO that are eager to engage the young viewers Vice attracts. Vice said it was now worth at least $4 billion, with nearly $1 billion in projected revenue for 2015. It is a long way from Vice’s humble start as a free magazine in 1994.
But even as cash flows freely in Vice’s direction, the company is trying to keep its brash, insurgent image. At the party on Friday, it plied guests with beers and cocktails. Its apparently unrehearsed presentation to advertisers was peppered with expletives. At one point, the director Spike Jonze, a longtime Vice collaborator, asked on stage if Mr. Smith had been drinking.
“My assistant tried to cut me off,” Mr. Smith replied. “I’m on buzz control.”
Now, Vice is on the verge of getting its own cable channel, which would give the company a traditional outlet for its slate of non-news programming. If all goes as planned, A&E Networks, the television group owned by Hearst and Disney, will turn over its History Channel spinoff, H2, to Vice.
The deal’s announcement was expected last week, but not all of A&E’s distribution partners — the cable and satellite TV companies that carry the network’s channels — have signed off on the change, according to a person familiar with the negotiations who spoke on the condition of anonymity because the talks were private.
A cable channel would be a further step in a transformation for Vice, from bad-boy digital upstart to mainstream media company.
Keen for the core audience of young men who come to Vice, media giants like 21st Century Fox, Time Warner and Disney all showed interest in the company last year. Vice ultimately secured $500 million in financing from A&E Networks and Technology Crossover Ventures, a Silicon Valley venture capital firm that has invested in Facebook and Netflix.
Those investments valued Vice at more than $2.5 billion. (In 2013, Fox bought a 5 percent stake for $70 million.)
Then in March, HBO announced that it had signed a multiyear deal to broadcast a daily half-hour Vice newscast. Vice already produces a weekly newsmagazine show, called “Vice,” for the network. That show will extend its run through 2018, with an increase to 35 episodes a year, from 14.
Michael Lombardo, HBO’s president for programming, said when the deal was announced that it was “certainly one of our biggest investments with hours on the air.”
Vice, based in Brooklyn, also recently signed a multiyear $100 million deal with Rogers Communications, a Canadian media conglomerate, to produce original content for TV, smartphone and desktop viewers.
Vice’s finances are private, but according to an internal document reviewed by The New York Times and verified by a person familiar with the company’s financials, the company is on track to make about $915 million in revenue this year.
It brought in $545 million in a strong first quarter, which included portions of the new HBO deal and the Rogers deal, according to the document. More of its revenue now comes from these types of content partnerships, compared with the branded content deals that made up much of its revenue a year ago, the company said.
Mr. Smith said the company was worth at least $4 billion. If the valuation gets much higher, he said he would consider taking the company public.
“I don’t care about money; we have plenty of money,” Mr. Smith, who is Vice’s biggest shareholder, said in an interview after the presentation on Friday. “I care about strategic deals.”
In the United States, Vice Media had 35.2 million unique visitors across its sites in March, according to comScore.
The third season of Vice’s weekly HBO show has averaged 1.8 million viewers per episode, including reruns, through April 12, according to Brad Adgate, the director of research at Horizon Media. (Vice said the show attracted three million weekly viewers when repeat broadcasts, online and on-demand viewings were included.)
For years, Mr. Smith has criticized traditional TV, calling it slow and unable to draw younger viewers. But if all the deals Vice has struck are to work out, Mr. Smith may have to play more by the rules of traditional media. James Murdoch, Rupert Murdoch’s son and a member of Vice’s board, was at the company’s presentation on Friday, as were other top media executives.
“They know they need people like me to help them, but they can’t get out of their own way,” Mr. Smith said in the interview Friday. “My only real frustration is we’re used to being incredibly dynamic, and they’re not incredibly dynamic.”
With its own television channel in the United States, Vice would have something it has long coveted even as traditional media companies are looking beyond TV. Last year, Vice’s deal with Time Warner failed in part because the two companies could not agree on how much control Vice would have over a 24-hour television network.
Vice said it intended to fill its new channel with non-news programming. The company plans to have sports shows, fashion shows, food shows and the “Gaycation” travel show with the actress Ellen Page. It is also in talks with Kanye West about a show.
It remains to be seen whether Vice’s audience will watch a traditional cable channel. Still, Vice has effectively presold all of the ad spots to two of the biggest advertising agencies for the first three years, Mr. Smith said.
In the meantime, Mr. Smith is enjoying Vice’s newfound role as a potential savior of traditional media companies.
“I’m a C.E.O. of a content company,” Mr. Smith said before he caught a flight to Las Vegas for the boxing match on Saturday between Floyd Mayweather Jr. and Manny Pacquiao. “If it stops being fun, then why are you doing it?”