Title of Presentation

Drill Hole Preparation

PT SAPTAINDRA SEJATIQULITY CIRCLE PROJECT6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

11. Background

Terdapat lubang yang Colapse Lubang colapse disebabkan oleh runtuhnya dinding lubang, sehingga kedalaman lubang berkurang secara signifikan. Hal ini myebabkan lubang tidak dapat digunakan.Menurut Borivoje et.al, University of Zagreh, Faculty of Mining, Geology and Petroleum, terdapat beberap faktor penyebab keruntuhan lubang drilling

Dari penelitian di atas, salah satu penyebab lubang collapse adalah adanya lapisan struktur yang bersifat loose seperti pasir atau kerikil

Sand/Gravel6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

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1. BackgroundLokasi Material Pasir Pit North ADMO (Pit ADMO memiliki struktur pasir kuarsa)

T120T110T121: Batupasir kuarsa: Batubara12345Interburden T110 T120 Roof T120 Batupasir KuarsaBatupasir kuarsa masif sisipan konkresi oksida besi(medium to coarse grain)

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Batupasir kuarsa masif(medium to coarse grain)2

Batupasir kuarsa dengan fragmen batubara cross bedding(fine to very coarse grain)3

Batupasir kuarsa laminasi(fine to very fine grain)4Batupasir kuarsa graded bedding(fine to very fine grain)

5: Batu pasir kuarsa6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

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1. BackgroundVolume Material Pasir Kuarsa

Volume pasir kuarsa Pit North= 3,100,603 bcmVolume pasir kuarsa Pit Central= 5,313,073 bcm

Total Loss Drill Hole

Total loss drill hole merupakan total lubang drilling yang diperkirakan collapse akibat lokasi yang berpasirLubang collapse = volume material berpasir / volume efek ledakan tiap lubang

Burden= 8 mSpacing= 9 mDepth= 8 mVolume efek tiap lubang blasting= 8 x 9 x 8 = 576 bcm/hole

Total lubang collapse Pit North= 3,100,603 / 576= 5,383 holesTotal lubang collpase Pit Central= 5,313,073 / 576= 9,224 holes

Note: Volume berdasarkan design 2015 (Jan15-Dec15)6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

42. TheoryAlternative Solusi

Kondom berfungsi untuk mencegah runtuhnya dinding lubang.Kondom akan dimasukan sesaat setelah drilling machine menarik root dari dalam lubang.Pemicu ledak, handak dan material stemming akan dipampatkan ke dalam kondom tersebut.Solusi ini tidak memerlukan analisis mendalam, hanya saja perlu diperhitungkan cost dan kebutuhan man power untuk pemasangan pipa kondom pada lubang drill

Chemical disemprotkan ke dinding lubang untuk meningkatkan kohesifitas material penyusu dnding lubangChemical akan membentuk lapisan keras pada dinding lubangSelain melapisi, chemical juga akan meresap ke dalam material lubang hingga ke crack point.Chemical tidak akan mempengaruhi kualitas peledakan dan tidak menimbulkan kontaminasi terhadap lingkunganAnalisis chemical pada slide selanjutnya6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

52. TheoryKapasitas SprayerUnit drilling machin (DM) memliki tangki air dan alat penyemprot air (water sprayer) D245S (DM007).Water prayer terletak berdekatan dengan mata bor, water sprayer ini biasanya digunakan untuk menyemprotkan udara saja. hal ini berfungsing untuk flushing, sehingga tanah hasil bor tedorong ke permukaan lubang.

Tulisan di samping ini merupakan spesifikasi dari water tank dan water spray yang ada pada D245S.

Sehingga dapat diketahui bahwa kapasitas water tank = 454 liter air dan kapasitas semprot = 0.56 L/second air.

Cara Kerja SprayerTangki air diisi dengan larutan chemical sebanyak 454 LCairan chemical ini akan disemprotkan oleh sprayer ke arah dinding lubang drillingPenyemprotan dilakukan saat root diangkat ke permukaan lubangPenyemprotan dilakukan dengan debit tertentu akan dianalisis pada slide selanjutnyaDebit penyemprotan akan disesuaikan dengan kebutuhan chemical untuk melapisi dinding lubang & daya serap chemical ke dalam material dindingSetelah beberapa saat cairan akan mengeras dan meingkatkan kohesifitas (stabilitas) material dinding lubang

6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

62. TheoryKebutuhan Chemical

LLMenentukan Jarak PatahanDari gambar di samping, terlihat bahwa lapisan pasir (dengan butiran lebih besar) akan runtuh saat pengeboran. Jarak runtuhan L merupakan jarak antara dinding lubang dan titik patah material

Penelitian oleh See Hong Ong borehole stability menyetakan bahwa tiap batuan memiliki failure criteria.

Failure ciretia = exeternal strength > capacity strength = t > nSpesifikasi material batuan kuarsa:

Tensile strength (uji Lab)= 0.38 MpaKohesivitas= 10.6 MPa

ttn

6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

72. Theory1. Menentukan Jarak Patahan

Menentukan nilai W gaya berat yang menyebabkan gelincirDiketahui:Massa jenis kuarsa (1)= 2.4 ton/m3Massa jenis OB clay (2)= 2.6 ton/m3Tensile strength (t)= 0.38 MpaKohesifitas (c)= 10.6 MpaDiameter lubang= 20 cmKedalaman lubang (t)= 800 cmTebal lapisan sandstone (t1)= 600 cmTebal lapisan OB clay= 200 cmJarak ke pusat retakan (L)= 57.11 cm trial hingga W = n

AnalisisKeliling lubang (k)= 22/7 x 20 = 62.86 cm2Volume sandstone= 600 x 57.11 x 62.86 = 2,153,778 cm3Volume OB clay= 200 x 57.11 x 62.86 = 717,926 cm3Gaya pendorong (W)= {2,153,778 x (2.4/1000)} + {717,926 x (2.6/1000)}= 69.02 kN

Total kemampuan tahan= Tensile strength + kohesifitas= (0,38+10,6) / 9.81 x 100= 111.93 kg/cm2Luas bidang tahan= 62,86 x = 62.86 cm2Gaya penahan (n)= (111.93 x 62.86)*9.81/1000= 69.02 kNJadi jarak pusat retakan dari dinding lubang blasting = 57.11 cm = 570.11 mm6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

82. Theory2. Menentukan Pengaruh Tebal Lapisan Sandstone dan Jarak Pusat Retakan

Asumsi analisis:Material kuarsa terletak di dasar lubang, dengan ketebalan tertentu.Kedalaman lubang bor = 8 meter. Tebal lapisan OB clay = Kedalaman Lubang Tebal Sandstone

Hasil analisis:Jika lapisan sandstone semakin tebal, maka jarak pusat retakan akan semakin jauh.6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

92. Theory3. Menentukan Kebutuhan Volume Chemical

AALLDD1Drill HoleDiketahui:Diameter lubang (D)= 20 cmDiameter area retakan (D1)= 2 x L = 2 x 57.11 = 134.22 cmLuas lubang (A1)= 0.25 x 22/7 x 202= 314 cm2Luas area retakan (A2)= 0.25 x 22/7 x 134.222= 14154 cm2

Sudut geser internal ()= 380Tebal lapisan retakan (t2)= tan (380) x L = tan (380) x 57.11 = 44.62 cmPorositas (p)= 0.05Volume chemical= (13154 314) x 44.62 x 0.05 = 30874 cm3= 30.87 LiterLt2

6/3/2015 1:23 PM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

102. Theory3. Menentukan Performa Chemical

Drill Hole6/3/2015 1:50 PM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

112. TheoryDrill holeKondomDrill holeSprayerDrill holeSprayer= Chemical= Dinding lubang6/3/2015 9:08 AM 2007 Microsoft Corporation. All rights reserved. Microsoft, Windows, Windows Vista and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.The information herein is for informational purposes only and represents the current view of Microsoft Corporation as of the date of this presentation. Because Microsoft must respond to changing market conditions, it should not be interpreted to be a commitment on the part of Microsoft, and Microsoft cannot guarantee the accuracy of any information provided after the date of this presentation. MICROSOFT MAKES NO WARRANTIES, EXPRESS, IMPLIED OR STATUTORY, AS TO THE INFORMATION IN THIS PRESENTATION.

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