2009年7月30日 星期四

Gas metal arc welding

To perform gas metal arc welding, the basic necessary equipment is a welding gun, a wire feed unit, a welding power supply, an electrode wire, and a shielding gas supply.

Most applications of gas metal arc welding use a constant voltage power supply
Alternating current is rarely used with GMAW; instead, direct current is employed and the electrode is generally positively charged(DCEP)

Electrode
The selection of electrode depends on the process variation being used, the composition of the metal being welded, the joint design, and the material surface conditions.
All electrode contain deoxidizing metals such as silicon, manganese, titanium, and aluminum in small percentages to help prevent oxygen porosity, and some contain denitriding metals such as titanium and zirconium to avoid nitrogen porosity.[9]
The diameters of the electrodes used in GMAW typically range from 0.7 to 2.4 mm (0.028–0.095 in), but can be as large as 4 mm (0.16 in). The smallest electrodes are associated with short-circuiting metal transfer, while the pulsed spray mode generally uses electrodes of at least 1.6 mm (0.06 in).[10]

Shielding gas
Shielding gases are necessary for gas metal arc welding to protect the welding area from atmospheric gases such as nitrogen and oxygen, which can cause fusion defects, porosity, and weld metal embrittlement if they come in contact with the electrode, the arc, or the welding metal. This problem is common to all arc welding processes, but instead of a shielding gas, many arc welding methods utilize a flux material which disintegrates into a protective gas when heated to welding temperatures. In GMAW, however, the electrode wire does not have a flux coating, and a separate shielding gas is employed to protect the weld. This eliminates slag, the hard residue from the flux that builds up after welding and must be chipped off to reveal the completed weld.
The choice of a shielding gas depends on several factors, most importantly the type of material being welded and the process variation being used. Pure inert gases such as argon and helium are only used for nonferrous welding; with steel they cause an erratic arc and encourage spatter (with helium) or do not provide adequate weld penetration (argon). Pure carbon dioxide, on the other hand, allows for deep penetration welds but encourages oxide formation, which adversely affect the mechanical properties of the weld. Its low cost makes it an attractive choice, but because of the violence of the arc, spatter is unavoidable and welding thin materials is difficult. As a result, argon and carbon dioxide are frequently mixed in a 75%/25% or 80%/20% mixture, which reduces spatter and makes it possible to weld thin steel workpieces.
Argon is also commonly mixed with other gases, such as oxygen, helium, hydrogen, and nitrogen. The addition of up to 5% oxygen encourages spray transfer, which is critical for spray-arc and pulsed spray-arc GMAW. However, more oxygen makes the shielding gas oxidize the electrode, which can lead to porosity in the deposit if the electrode does not contain sufficient deoxidizers. An argon-helium mixture is completely inert, and is used on nonferrous materials. A helium concentration of 50%–75% raises the voltage and increases the heat in the arc, making it helpful for welding thicker workpieces. Higher percentages of helium also improve the weld quality and speed of using alternating current for the welding of aluminum. Hydrogen is added to argon in small concentrations (up to about 5%) for welding nickel and thick stainless steel workpieces. In higher concentrations (up to 25% hydrogen), it is useful for welding conductive materials such as copper. However, it should not be used on steel, aluminum or magnesium because of the risk of hydrogen porosity. Additionally, nitrogen is sometimes added to argon to a concentration of 25%–50% for welding copper, but the use of nitrogen, especially in North America, is limited. Mixtures of carbon dioxide and oxygen are similarly rarely used in North America, but are more common in Europe and Japan.
Recent advances in shielding gas mixtures use three or more gases to gain improved weld quality. A mixture of 70% argon, 28% carbon dioxide and 2% oxygen is gaining in popularity for welding steels, while other mixtures add a small amount of helium to the argon-oxygen combination, resulting in higher arc voltage and welding speed. Helium is also sometimes used as the base gas, to which smaller amounts of argon and carbon dioxide are added. Additionally, other specialized and often proprietary gas mixtures claim to offer even greater benefits for specific applications.[11]
The desirable rate of gas flow depends primarily on weld geometry, speed, current, the type of gas, and the metal transfer mode being utilized. Welding flat surfaces requires higher flow than welding grooved materials, since the gas is dispersed more quickly. Faster welding speeds mean that more gas must be supplied to provide adequate coverage. Additionally, higher current requires greater flow, and generally, more helium is required to provide adequate coverage than argon. Perhaps most importantly, the four primary variations of GMAW have differing shielding gas flow requirements—for the small weld pools of the short circuiting and pulsed spray modes, about 10 L/min (20 ft³/h) is generally suitable, while for globular transfer, around 15 L/min (30 ft³/h) is preferred. The spray transfer variation normally requires more because of its higher heat input and thus larger weld pool; along the lines of 20–25 L/min (40–50 ft³/h).[12]

The orientation of the gun is also important—it should be held so as to bisect the angle between the work pieces; that is, at 45 degrees for a fillet weld and 90 degrees for welding a flat surface. The travel angle or lead angle is the angle of the torch with respect to the direction of travel, and it should generally remain approximately vertical. However, the desirable angle changes somewhat depending on the type of shielding gas used—with pure inert gases, the bottom of the torch is out often slightly in front of the upper section, while the opposite is true when the welding atmosphere is carbon dioxide.[14

SAFETY HAZARD S INCLUDE
Extreme heat and flame
Ultraviolet light
Particulate matter
Carbon monoxide
Ozone
GLOBULAR TRANSFER
As the weld is made, a ball of molten metal from the electrode tends to build up on the end of the electrode, often in irregular shapes with a larger diameter than the electrode itself. When the droplet finally detaches either by gravity or short circuiting, it falls to the workpiece, leaving an uneven surface and often causing spatter.
limited to flat and horizontal welding positions

tendency to produce high heat, a poor weld surface, and spatter.
uses carbon dioxide,
high deposition rate,

SHORT CIRCUIT TRANSFER
Molten droplets form on the tip of the electrode, but instead of dropping to the weld pool, they bridge the gap between the electrode and the weld pool as a result of the greater wire feed rate. This causes a short circuit and extinguishes the arc, but it is quickly reignited after the surface tension of the weld pool pulls the molten metal bead off the electrode tip.
This process is repeated about 100 times per second, making the arc appear constant to the human eye.
possible to weld thinner materials
better weld quality and less spatter than the globular variation, and it allows for welding in all positions but slower


SPRA Y TRANSFER :
Molten metal droplets (with diameters smaller than the electrode diameter) are rapidly passed along the stable electric arc from the electrode to the work piece
eliminating spatter and resulting in a high-quality weld finish.
high amounts of voltage and current are necessary
used only on workpieces of thicknesses above about 6 mm (0.25 in).
it is often limited to flat and horizontal welding position
The maximum deposition rate for spray arc GMAW is relatively high; about 60 mm/s (150 in/min).[22



PULSE TRANSFER

Based on the principles of spray transfer but uses a pulsing current to melt the filler wire and allow one small molten droplet to fall with each pulse.
The pulses allow the average current to be lower, decreasing the overall heat input and thereby decreasing the size of the weld pool and heat-affected zone while making it possible to weld thin work pieces
The smaller weld pool gives the variation greater versatility, making it possible to weld in all positions.
it requires a special power source capable of providing current pulses with a frequency between 30 and 400 pulses per second.

Turned Process

Turned part include :i) Bolt ,ii) Shafts ,iii) Spindle ,iv) Washer.
Three motion involved in Lathe turning are
The rotating motion of the work piece is called ‘Cutting or main motion’. The speed at which the material is removed from work piece by the cutting edge is called ‘cutting speed’
The cutting tool moves forward at a uniform rate forming a continuous chip (Feed motion)
The turning tool is set to desire depth of cut( Adjusting motion)

STRAIGHT TURNING -The work pieces are given cylindrical shape by straight turning , in which cutting tool move parallel to the axis of the turning spindle.

FACING The work pieces are given plane surface by facing , in which cutting tool move perpendicular to the axis of the turning spindle.
TAPER TURNING:The work pieces are given taper shape by taper turning operation , in which cutting tool move at angle to the axis of the turning spindle.


Center lathe , engine lathe and longitudinal turning lathes are used interchangeably

HEAD STOCK In the head stock (Picture) the main spindle on the bearings transmit the rotary motion to the work piece.
In most cases spindles are hollow so as to guide the bar stock through
Bearing :plain bearing , thrust bearing , ball and roller bearing
Head of spindle is provided with a thread to fix chuck and also provided with tapered hole to accommodate centers
Spindle is driven by motor through gear train

CARRIAGE :Supports and carries cutting tool
Contains feed mechanism and its adjustment
Consists of saddle , cross slide , compound slide , tool holder and apron.
The saddle and the cross slide are either operated by feed shaft or the leadscrew

TAILSTOCK:Serves as a support for turning long work piece
Provided with MORSE taper to accommodate
center , twist drill, boring tool ,reamer
Tail stock can be offset for taper turning
BED :Carries all lathe parts
The carriage and tailstock move on the guide way which are usually V and flat shaped.
Turning tool can be made of unalloyed tool steel, alloy tool steel, cemented carbide and diamond tip
Shank serves the purpose of clamping
Tool point consists of cutting edges
Cut face is the surface on the work piece which is formed by the cutting edge of the tool
The machined surface is the surface of the work piece obtained by the cutting process



The top face is the surface on which the chip curls .
The clearance face is the surface of the tool point, directed against the cut face.
The clearance angle is the angle between top face and clearance face
The rake angle is the angle between normal of the cut face and the top face
Clearance ,wedge and rake angle add up to 90 degree
The primary cutting edge is the cutting edge on the feed side
The secondary cutting edge is the cutting edge subsequent to the primary cutting edge


The Plan angle is situated between the primary cutting edge and machine surface. When turning with large plan angle the thickness of the chip is small , the cutting pressure is ditributed on a short portion of the cutting edge , tool life shortened and vice versa.

The nose angle is enclosed between primary cutting edge and secondary cutting edge tool with small nose angle blunt quickly.

The inclination angle determine the position of the primary cutting edge towards the horizontal line

Type of cutting tool include roughing tool , finishing tool and side tools

Toolpost include ordinary tool post and four way tool post.

Cutting tools should be set at center to obtain optimun results .

Cutting Speed =22/7 *RPM *D cirmeferential length of chip cut in one minute , depends on 1) Work piece material,2) Cutting tool materials,3) Cross section of the chip , 4)Cooling ,5) Machine Design

Feed means longitidunal distance travel for one full turning of work piece

Depth of cut means amount of penetration into the work piece to obtain a desired size.

A Typical operation plan sequence for manufacturing of bolt are
1) Chucking
2)Roughing and finishing of 1st step
3)Turning to length and deburing of 1st step
4)Rechucking
5)Roughing , finishing , turning to length and deburring of 2nd step

教育是要培养健全人格

http://www.nanyang.com/index.php?ch=29&pg=26&ac=984272
南洋言论 -





教育视窗: 教育是要培养健全人格 2009/07/30 17:58:18
●吴和豪







据报道,教育部将削减学校3个科目,即音乐、体育及科学节数,以增加英文学习时间。
本人不十分同意这种的做法,因为教育本来的目的就是要培养每一个人成为有健全人格的人。我小学就读于槟城的辅友小学,还记得辅友小学的校歌的一段里有提及三语并重,四育同修;三语并重就是注重中文,国文及英文,而四育同修就是蔡元培教育论集里提及的体育、智育、德育和美育。这四育是一样重要,不可放松一项。因此我们不能为了达到特定的学术指标, 而忽视了学童们其他方面的发展,而使到国家社会不能取得全面及均衡的发展。

通过歌唱教导语文

我本身的看法是与其削减音乐、体育及科学节数,不如用创意的方法把这些科目与英语教学结合而达到一石二鸟的功能。以我本身教日语的经验来谈,如果处理得好,通过歌唱来教导语文不但能制造更轻松的学习环境,同时,也能提高学员对语文学习的兴趣。

世界日益进步,科技不断变化,而世界各地教育制度及方法也不断地演变。为了使到我国的教育制度系统能不断改进及提升我国作为国际性的教育中心,我国也有需要向其他国家如印度及瑞士学习,学习这些国界在保留自己的传统语言同时,也能够有效提高学生的英文应用能力。

在制定教育制度的时候,我们必须考量每个学生有不同的质量及智能。据哈佛卡尔纳博士(Howard Gardner)的理论,每个身心正常的人都有8种的智能。这8种智能包括了言语智能、音乐智能、数学逻辑智能、空间观想智能、体力智能、交际智能、个人领悟的智能及与大自然沟通的智能。每个人都有这8种的智能,但强弱的程度依个人的成长环境而不同。

如果能够以这原理来掌握学生的学习习惯及态度,学校的老师就可以依学生的本性制定适合的方法教导学生。从古到今,教育的目的是一样的,今天我们提及全面及均衡的发展,而以前圣贤们也需要精通四书,五经及六艺。总而言之,教育本来的目的就是要培养每一个人成为有健全人格的人。

Skim subsidi kerajaan wujudkan kestabilan

http://www.bharian.com.my/klikkhas/pilihanraya/Berita/Rencana/20080218150316/Article/indexrencana_html



Skim subsidi kerajaan wujudkan kestabilan
Oleh Goh Hoe Hoe
ISU subsidi dan negara kebajikan dibangkitkan pihak pembangkang. Namun, dalam sebuah negara majmuk seperti Malaysia, perkara ini perlu difahami dan tidak dipesong oleh pihak yang cuba menjadi juara.

Mengikut laporan akhbar 26 Januari lalu, Setiausaha Agung DAP, Lim Guan Eng antara lain dipetik sebagai berkata bahawa cara paling baik untuk mengurangkan beban rakyat adalah dengan memberikan bantuan wang sebanyak RM6,000 kepada keluarga berpendapatan kurang RM6,000 setahun dan RM3,000 bagi individu berpendapatan kurang RM3,000 setahun.

Pada pendapat saya, cadangan itu tidak praktikal dan tidak sesuai dengan budaya orang Malaysia. Cadangan Lim lebih kurang serupa dengan skim bantuan pengangguran yang diamalkan di negara Barat.
Skim itu jika dilaksanakan di Malaysia, akan membawa kesan sangat buruk. Ia akan menghasilkan orang yang malas bekerja dan tidak berusaha, seterusnya merendahkan kadar pengeluaran negara dan kemampuan bagi negara untuk bersaing, akhirnya akan mewujudkan kemelesetan ekonomi di negara kita.
Lim juga membuat ulasan bahawa subsidi yang diberi oleh kerajaan ke atas barang keperluan utama tidak berguna. Adakah ini satu pandangan yang melampau? Skim subsidi ke atas barang keperluan utama bukan saja diamalkan di negara kita, malah juga diamalkan oleh negara maju seperti Jepun.

Di Jepun, subsidi yang diberikan oleh kerajaan Jepun ke atas beras adalah jauh lebih tinggi daripada harga pasaran beras, iaitu kira-kira 20 kali ganda. Tetapi langkah ini tidak menjejaskan prestasi ekonomi Jepun, sebaliknya memberi kesan baik dalam membentuk masyarakat yang stabil di Jepun.

Apabila pihak pentadbir menjalankan pentadbiran, mereka bukan saja mesti mengambil kira kos perakaunan dan kos pengeluaran, malah harus juga memberikan keutamaan terhadap kestabilan masyarakat, keperluan rakyat dan kemampuan bagi negara kita untuk bersaing pada masa depan.

Tujuan utama Kerajaan Malaysia memberikan subsidi ke atas barang dan perkhidmatan utama ialah untuk memastikan semua orang, yang tua dan muda, cukup makan dan hidup selesa.

Ini bagi membolehkan orang dewasa dapat menumpukan perhatian kepada pekerjaan mereka dan seterusnya memberi sumbangan kepada perkembangan ekonomi negara, supaya anak kita dapat menumpukan perhatian kepada pelajaran mereka.

Ini seterusnya menjadi mereka golongan yang dapat bersaing pada masa depan dan memberikan sumbangan mereka kepada perkembangan ekonomi negara.
Skim subsidi bukan saja baik untuk pengguna, malah untuk peniaga kerana dengan wujudnya skim subsidi, kuasa membeli pengguna dapat dikekal, perniagaan maju dan hasil cukai pendapatan kerajaan dapat juga dikekalkan.

Oleh itu, langkah kerajaan memberikan subsidi yang berpatutan adalah satu langkah bijak untuk memastikan kestabilan masyarakat dan perkembangan ekonomi.

Dalam pentadbiran negara, kita boleh meniru piawaian yang ditetapkan oleh negara Barat, sistem demokratik yang berasal dari Yunani (Greek) dan mekanisme pasaran bebas atau hukum pengagihan semula yang dicadangkan oleh Karl Marx.

Sebaliknya kita juga mesti mengikut cara Timur seperti sikap kesederhanaan dan konsep masyarakat yang bersatu padu yang diajar oleh Confucious.

Masyarakat bersatu padu adalah satu konsep yang disebutkan oleh Confucious, ahli falsafah handal bangsa China dalam bukunya bertajuk Rakaman Istiadat. Confucious berpendapat untuk mewujudkan satu masyarakat yang aman dan progresif, pentadbir mesti memberikan keutamaan kepada kebajikan rakyat.

Pegawai kerajaan mestilah terdiri daripada golongan berilmu, berkebolehan dan berbudi pekerti. Pegawai kerajaan mesti ikhlas untuk membentuk satu masyarakat berbilang budaya yang harmoni.

Dalam satu masyarakat yang ditadbir dengan sempurna, orang tua meneruskan perjalanan hidup mereka sampai titik akhir penuh dengan maruah dan kegembiraan, orang dewasa yang sihat diberi peluang untuk bekerja dan menunjukkan kebolehan mereka, manakala anak diasuh dan dididik dengan baik.

Orang yang kurang bernasib dan kurang berkeupayaan pula diberi jagaan. Setiap orang diberikan tugas dan dihormati, setiap keluarga hidup dengan sejahtera. Tidak ada orang yang suka membazirkan sumber pengeluaran dan juga tidak ada orang yang mahu menyorok sumber pengeluaran untuk mencari kekayaan.

Tidak ada orang yang enggan berusaha dan tidak ada orang yang berusaha semata mata untuk kepentingan diri sendiri saja.

Masyarakat yang mempunyai ciri itu, digelar sebagai masyarakat yang bersatu padu. Kerajaan menunjukkan pencapaian yang baik dalam usaha untuk mempertingkatkan taraf hidup rakyat , mewujud masyarakat yang aman dan maju.

Hidupkan teknologi hijau sebagai industri strategik

http://www.bharian.com.my/Friday/Rencana/20090730231809/Article/index_html
'TEKNOLOGI hijau' bukan frasa baru dalam konteks pembangunan teknologi dan inovasi. Pada hemat saya, ada tiga komponen penting memastikan tahap 'kehijauan' sesuatu teknologi, iaitu kesan kepada alam sekitar, manfaat kepada pengguna dan pemangkin kehidupan lestari. Kesan kepada alam sekitar boleh ditentukan menerusi kaedah analisis kitar hayat (LCA) atau pengiraan tapak ekologi.

Manfaat kepada pengguna pula membabitkan bukan saja pengurangan kos modal dan operasi, malah turut membabitkan peningkatan keselamatan, kemudahan dari segi penggunaan dan praktikal. Misalnya 'kereta hijau' seharusnya murah dan menjimatkan dari segi bahan api. Selain itu, reka bentuk kereta itu mestilah lebih selamat, menarik dan tidak sukar dipandu.

Teknologi hijau juga pemangkin kehidupan lestari. Justeru, teknologi hijau perlu direkabentuk untuk menyubur minda lestari, kehidupan mesra alam, mengurang pembaziran, menyemarak budaya, mementing agama dan memugar ekosistem.



Sebagai contoh pakaian, 'pakaian hijau' bukan saja dihasil menerusi bahan mentah dan proses pembikinan mesra alam, malah perlu disesuaikan dengan iklim setempat (misalnya tidak tebal bagi pengguna di kawasan beriklim panas supaya tidak memerlukan pendingin hawa), fesyen tidak mencolok mata atau mendedahkan aurat.

Semua aspek ini mendefinisikan 'teknologi hijau' bukan saja dari segi kaedah dan alat pembikinan sesuatu produk atau perkhidmatan, malah cara hidup lestari. Teknologi hijau semakin diperlukan bagi menangani keperluan setempat seperti pengurangan tahap pencemaran dalam sektor perkhidmatan air dan penjanaan tenaga lestari.

Malah teknologi hijau juga boleh dibangunkan sebagai industri strategik seperti dimulakan Jerman dan Jepun sejak 1990-an. Disebabkan teknologi hijau ialah suatu konsep berkaitan ciri teknologi dan idealisme lestari, maka penggunaannya meluas dalam seluruh sektor.

Ketika ini, konsep 'ICT hijau', 'bandar lestari', 'korporat hijau' dan 'kerajaan lestari' semakin berkembang daripada perkakasan, sistem perolehan, peraturan, tata cara sehingga kerangka dasar dan budaya kerja.

Sebagai contoh antara komponen penting dalam sesebuah kerajaan lestari ialah sistem perolehan memberi keutamaan kepada barang, perkhidmatan, proses dan hasil mesra alam. Dalam konteks pembinaan infrastruktur baru misalnya, tumpuan tidak hanya kepada penyediaan bangunan atau kelengkapan, tetapi turut membabitkan konsep, kaedah dan barang binaan, penggunaan tenaga dan utiliti lain dan budaya lestari di kalangan penghuni bangunan terbabit.

Dengan harga minyak masih tidak menentu dan kegusaran terhadap kesan peningkatan suhu bumi, maka peranan teknologi hijau dijangka lebih mendesak dan kritikal. Pada hemat saya, itulah antara faktor utama Perdana Menteri, Datuk Seri Najib Razak menubuhkan Kementerian Tenaga, Teknologi Hijau dan Air (KeTTHA).

Ketika melancarkan Dasar Teknologi Hijau Negara (DTHN) pada 24 Julai lalu, Najib menegaskan bahawa teknologi hijau akan dibangunkan sebagai pemacu pertumbuhan ekonomi negara ke arah pembangunan lestari.

Sehubungan itu, empat tonggak DTHN digariskan iaitu mencari ketidakbergantungan tenaga dan promosi kecekapan tenaga, melestarikan alam sekitar, meningkatkan pembangunan ekonomi negara melalui penggunaan teknologi hijau dan meningkatkan kualiti hidup masyarakat.

Antara objektif DTHN ialah untuk meningkatkan keupayaan bagi inovasi dalam pembangunan dan daya saing teknologi hijau pada persada antarabangsa. Ketika ini memang banyak inovasi dilaksanakan, khususnya dalam teknologi berkaitan rawatan air dan air sisa secara lebih lestari dan kreatif.

Memang teknologi itu diperlukan dalam situasi kualiti dan kuantiti sumber air semakin terjejas. Malah pasaran teknologi itu cukup besar. Di negara maju, tumpuan adalah untuk membaikpulih kemudahan sedia ada dan meningkatkan keberkesanannya. Ini termasuk dalam sektor bekalan air, pembetungan, pengurusan air industri dan sistem kejuruteraan, misalnya dalam kabin kapal terbang dan kapal laut.

Di negara membangun pula, teknologi air lestari diperlukan untuk menyediakan kemudahan kepada penduduk yang masih belum menikmati kemudahan bekalan air dan pembetungan. Menurut data Pertubuhan Bangsa-Bangsa Bersatu (PBB) pada 2002, bilangan penduduk di negara membangun tidak mendapat kemudahan bekalan air bersih ialah 1.1 bilion dan 2.4 bilion pembetungan.

Daripada jumlah itu, benua Asia paling ketara dengan 65 peratus penduduk masih belum mendapat bekalan air bersih dan 80 peratus kemudahan pembetungan, berbanding Afrika 27 peratus (bekalan air) dan 65 peratus (pembetungan).

Asasnya sudah tersedia, iaitu DTHN. Matlamat sudah dizahirkan. Malah laluan sudah ditunjuk. Maka usaha perlu dipergiatkan untuk membolehkan penggunaan dan penjanaan teknologi hijau subur di Malaysia.

Seperti kata Najib, 'impian saya adalah supaya suatu hari nanti kita boleh hidup dalam persekitaran bersih, sihat dan berkualiti tinggi, yang semua bandar, perbandaran dan komuniti dibina berasaskan konsep teknologi hijau.'

Profesor Datuk Zaini Ujang ialah Naib Canselor Universiti Teknologi Malaysia (UTM) dan Pengerusi Majlis Kualiti Alam Sekeliling Malaysia

BHOPAL GAS TRAGEDYhttp://www.irastimes.org/bhopal_gas_tragedy.htm

BHOPAL GAS TRAGEDY




Eighteen years have gone by since the Bhopal Gas tragedy. The victims of the biggest industrial accident are yet to receive succour. “The Bhopal Gas Tragedy “ has been lost in the collective consciousness of the nation. Yes, life has to go on - we must light candles and offer prayers for the victims of September, 11 2001 - but do spare a thought for those who lost their lives in their devotion to duty.

I am talking of the “unhonoured,” “unwept” and “unsung” railwaymen who stood like “boys on the burning deck” and kept the wheels of Indian Railways turning.

Third of December 1984 dawned like any other day at Bhusaval Junction the heart of Central Railway operations. It was a pleasant bracing winter morning and it was “…business as usual….” The 00-00 hours to 08-00 hours shift in the Control Office was busy tying up the loose ends of the previous day’s operations and gathering information to plan the day’s work. The telephone lines were buzzing from different directions and all the ‘control boards’ were busy like the proverbial beehives. North bound trains towards Itarsi Junction, South bound trains towards Mumbai, West bound trains towards Surat and East bound trains towards Nagpur marked their progress on the control charts.

But wait! the Itarsi line was fading. Those were the days when railway communication was mainly through the overhead telegraph wires. Optic Fibre Cable was still in its infancy. It was the pre Sam-Pitroda days and telephone instruments were a luxury. There were no STD facilities and what was called a “lighting call” took a couple of hours to materialise!

At first the Bhusaval Control Office shrugged off the lack of communication with Itarsi as routine, but when the silence continued it was disquieting. The railways still had their more than 100 years old MORSE instruments functioning and there was a class of railwaymen which is extinct now called ‘Signallers’ who used the DOT-DASH-DOT method to raise Bhopal. Finally the headquarters control office at Mumbai confirmed that there was something seriously amiss at Bhopal which in those days was an area controlled from the Jhansi Railway Divisional Office. Communication to Bhopal was via Itarsi.

By about 6-00 a.m it was evident that a disaster had struck Bhopal. No trains were leaving Bhopal and those which entered just seemed to have disappeared into a ‘black hole’ till the yard was full and no more trains could be admitted.

The initial reports were almost flippant – “…. some evil fairy has struck and sleeping sickness has overtaken Bhopal….” Wild rumours started spreading. In the aftermath of the 1984 riots the militant Sikh organisations were blamed for everything.

Black 3rd December brought the news that people had been dropping dead like flies in Bhopal and those who could manage were scrambling into trains which were running away from Bhopal. There was a mass exodus with the Government functionaries abandoning Bhopal and commandeering whatever vehicles were available.



As the next shift railway workers streamed in at Bhopal they saw the horrifying sight of their colleagues slumped over at the workspot. Signalmen and Stationmasters in the busy NISHATPURA yard which was the epicentre of the gas leak had collapsed with the signal levers still in their hands. Since the signals did not turn green the engine drivers, died in their cabs dutifully waiting for the signals. Clerks at the booking windows had keeled over with the ticket boxes and the cash safe wide open. The only redeeming feature was that the deadly gas had struck without fear or favour and even thieves dare not enter Bhopal!

Back at the Bhusaval Control Office the full impact of the happenings at Bhopal was still sinking in. Plans were made to send medical aid and manpower to Bhopal to restart the operations.



In the glorious tradition of Indian Railways not one employee questioned the decision to send people to Bhopal. Whenever there is a disaster, man made or natural, it is ingrained in railwaymen to rush to the scene of the disaster and none will quit his post till the job is done. The last civilian to leave Tezpur when the Chinese invaded India in 1962 was the Station Master!

Meanwhile, rumours had spread that a second wave of poisonous gas, even deadlier than the first one, had broken loose and the steady exodus further swelled due to the rush of the panic stricken residents.



While these streams of humanity were going out of Bhopal, there was one band of railwaymen going towards Bhopal. In retrospect one may say “Fools rushed where angels feared to tread,” but at that point of time the Railwaymen and women of Itarsi, 90 kms. from Bhopal banded themselves together and set off in a caravan of road vehicles to the illfated city of Bhopal. Unmindful of the people exhorting them to go back, the unsung heroes armed with food and medicine, wended their way to Bhopal.



Nobody knew exactly what had happened except that some gas had engulfed Bhopal and as the sun rose the gas diffused and finally dispersed leaving in its wake thousands of humans choking, coughing and blinded. The “council of war” at the Bhusaval control office decided that a relief train should start immediately. On the presumption that only a nerve gas could disable people so rapidly, all the stocks of ATROPINE were commandeered along with hundreds of vials of eye drops.

The Special Train carrying a multidisciplinary team of railway employees including doctors and para-medics, covered the distance of 302 kms. from Bhusaval to Itarsi in 3 hours flat. When we reached Bhopal we were informed that the Government Administration had finally got their act together - probably shamed into action by the railwaymen who had proceeded from Itarsi.



We were told to organise relief operations in the Itarsi civil hospital. We found that the ATROPINE vials and “Visine” eye drops were useless. I still do not know whether there is an antidote to METHYL ISOCYANATE - the poisonous substance which had annihilated everyone near the Union Carbide Factory in Bhopal.



The sight at Itarsi was something straight out of Dante’s ‘Inferno.’ Dozens of men, women and children were writhing in agony and we watched them in horrified helplessness. Death was a welcome relief to the victims, their eyeballs swollen red and bursting, every breath bringing agony to their burning lungs. The screams of the tortured bodies were in different languages. As train after train went past Itarsi discharging the bodies of the victims of the monstrous gas, the famous cliché that “from Kashmir to Kanniyakumari Indian Railways is one” was poignantly apparent as we tried our best to soothe the victims in whatever language we could speak. Faced with their end these poor souls uncomplainingly requested that their next of kin should be informed and their belongings taken care of. I still cannot forget the poor blinded Malayalee boy holding my hands imploring me to convey some important news to his mother in Kerala.

The dying wish of a TTE (Travelling Ticket Examiner ) was that his settlement dues should be expedited and his family cared for. In his delirious death he kept apologising for abandoning his train and pressed the reservation chart into the hands of another railwayman. His sightless eyes failed to reveal that it was a doctor.



There was no way for postmortem to be performed and all the death certificates were signed with the words “Cardiac arrest due to unknown causes”.



The railways raced back to normality within 24 hours of the accident. Hundreds of railwaymen still bear the physical and mental scars of that black day.



When I joined the Railways I was asked to make a daily prayer that there should be no fatal railway accidents in my career and I do not have to remove mangled bodies from a train wreck. I never expected that I would live to see so many dead and dying humans around.

While we continue to pray for their souls, let us salute the railwaymen who tenaciously clung to their workspots and rushed to the scene of disaster.



V. Anand,

Ex-ADRM/BSL/CR,

Now GM/SR

The Chernobyl disaster http://en.wikipedia.org/wiki/Chernobyl_disaster

The Chernobyl disaster was a nuclear reactor accident at the Chernobyl Nuclear Power Plant in Ukraine, then part of the Soviet Union. It is considered to be the worst nuclear power plant disaster in history and the only level 7 instance on the International Nuclear Event Scale. It resulted in a severe release of radioactivity following a massive power excursion which destroyed the reactor. Two people died in the initial steam explosion, but most deaths from the accident were attributed to radiation.

On 26 April 1986 01:23:45 a.m. (UTC+3) reactor number four at the Chernobyl plant, near Pripyat in the Ukrainian Soviet Socialist Republic, exploded. Further explosions and the resulting fire sent a plume of highly radioactive fallout into the atmosphere and over an extensive geographical area. Four hundred times more fallout was released than had been by the atomic bombing of Hiroshima.[2]

The plume drifted over extensive parts of the western Soviet Union, Eastern Europe, Western Europe, Northern Europe, and eastern North America, with light nuclear rain falling as far as Ireland. Large areas in Ukraine, Belarus, and Russia were badly contaminated, resulting in the evacuation and resettlement of over 336,000 people. According to official post-Soviet data,[3] about 60% of the radioactive fallout landed in Belarus.

The accident raised concerns about the safety of the Soviet nuclear power industry, slowing its expansion for a number of years, while forcing the Soviet government to become less secretive. The countries of Russia, Ukraine, and Belarus have been burdened with the continuing and substantial decontamination and health care costs of the Chernobyl accident. It is difficult to accurately quantify the number of deaths caused by the events at Chernobyl, as the Soviet-era cover-up made it difficult to track down victims. Lists were incomplete, and Soviet authorities later forbade doctors to cite "radiation" on death certificates.[4]

The 2005 report prepared by the Chernobyl Forum, led by the International Atomic Energy Agency (IAEA) and World Health Organization (WHO), attributed 56 direct deaths (47 accident workers, and nine children with thyroid cancer), and estimated that there may be 4,000 extra cancer deaths among the approximately 600,000 most highly exposed people.[1] Although the Chernobyl Exclusion Zone and certain limited areas remain off limits, the majority of affected areas are now considered safe for settlement and economic activity.[5]