Why We Need Weld Procedure Testing

Components of a welding procedure
Parent material
• Type (Grouping)
• Thickness
• Diameter (Pipes)
• Surface condition)

Welding process
• Type of process (MMA, MAG, TIG, SAW etc)
• Equipment parameters
• Amps, Volts, Travel speed

Welding Consumables
• Type of consumable/diameter of consumable
• Brand/classification
• Heat treatments/ storage

belajar NDT

Apakah itu Non Destrctive Testing ?

Non destrtructive testing (NDT) adalah aktivitas tes atau inspeksi terhadap suatu benda untuk mengetahui adanya cacat, retak, atau discontinuity lain tanpa merusak benda yang kita tes atau inspeksi. Pada dasarnya, tes ini dilakukan untuk menjamin bahwa material yang kita gunakan masih aman dan belum melewati damage tolerance. Material pesawat diusahakan semaksimal mungkin tidak mengalami kegagalan (failure) selama masa penggunaannya.

Metode-Metode Non Destructive Testing meliputi:Visual Inspection
Sering kali cara ini merupakan langkah yang pertama kali diambil dalam hal NDT. Metode ini bertujuan menemukan cacat atau retak permukaan dan korosi. Dalam hal ini tentu saja adalah retak yang dapat terlihat oleh mata telanjang atau dengan bantuan lensa pembesar ataupun boroskop.

Liquid Penetrant Test

Metode Liquid Penetrant Test merupakan metode NDT yang paling sederhana. Metode ini digunakan untuk menemukan cacat di permukaan terbuka dari komponen solid, baik logam maupun non logam, seperti keramik dan plastik fiber. Melalui metode ini, cacat pada material akan terlihat lebih jelas. Caranya adalah dengan memberikan cairan berwarna terang pada permukaan yang diinspeksi. Cairan ini harus memiliki daya penetrasi yang baik dan viskousitas yang rendah agar dapat masuk pada cacat dipermukaan material. Selanjutnya, penetrant yang tersisa di permukaan material disingkirkan. Cacat akan nampak jelas jika perbedaan warna penetrant dengan latar belakang cukup kontras. Seusai inspeksi, penetrant yang tertinggal dibersihkan dengan penerapan developer.

 Magnetic Particle Inspection

adalah pengujian non-destruktif (NDT) untuk mendeteksi diskontinuitas permukaan dan bawah permukaan bahan feroelektrik seperti besi, nikel, kobalt, dan beberapa paduan mereka.Proses ini menempatkan sebuah medan magnetik ke bagian tersebut dan  potongan tersebut dapat termagnetisasi dengan magnetisasi langsung atau tidak langsung. Magnetisasi secara langsung terjadi ketika arus listrik dilewatkan melalui benda uji dan medan magnet terbentuk dalam materi. Sedangkan Magnetisasi tidak langsung terjadi ketika tidak ada arus listrik dilewatkan melalui benda uji, tetapi medan magnet diterapkan dari sumber luar.

Dengan menggunakan metode ini, cacat permukaan (surface) dan bawah permukaan (subsurface) suatu komponen dari bahan ferromagnetik dapat diketahui. Prinsipnya adalah dengan memagnetisasi bahan yang akan diuji. Adanya cacat yang tegak lurus arah medan magnet akan menyebabkan kebocoran medan magnet. Kebocoran medan magnet ini mengindikasikan adanya cacat pada material. Cara yang digunakan untuk memdeteksi adanya kebocoran medan magnet adalah dengan menaburkan partikel magnetik dipermukaan. Partikel-partikel tersebuat akan berkumpul pada daerah kebocoran medan magnet.

 Eddy Current Test

Tujuan utama dari metode pengujian baru adalah untuk mendeteksi dan menentukan kedalaman retak-seperti kerusakan di sudut ukur rel. Salah satu penyebab untuk ini adalah apa yang disebut pemuaian bahan material bahan  bahan rel karena kecepatan tinggi dan beban gandar besar. Metode pengujian baru ini didasarkan pada prinsip arus eddy

Inspeksi ini memanfaatkan prinsip elektromagnet. Prinsipnya, arus listrik dialirkan pada kumparan untuk membangkitkan medan magnet didalamnya. Jika medan magnet ini dikenakan pada benda logam yang akan diinspeksi, maka akan terbangkit arus Eddy. Arus Eddy kemudian menginduksi adanya medan magnet. Medan magnet pada benda akan berinteraksi dengan medan magnet pada kumparan dan mengubah impedansi bila ada cacat.

 Ultrasonic Inspection

Pengujian ultrasonik (UT) menggunakan energi suara berfrekuensi tinggi untuk melakukan pemeriksaan dan membuat pengukuran. Pemeriksaan ultrasonik dapat digunakan untuk deteksi cacat / evaluasi, pengukuran dimensi, dan banyak lagi. Prinsip pemeriksaan umum adalah pulsa / echo metode konfigurasi inspeksi khas digambarkan sebagai berikut

Prinsip yang digunakan adalah prinsip gelombang suara. Gelombang suara yang dirambatkan pada spesimen uji dan sinyal yang ditransmisi atau dipantulkan diamati dan interpretasikan. Gelombang ultrasonic yang digunakan memiliki frekuensi 0.5 – 20 MHz. Gelombang suara akan terpengaruh jika ada void, retak, atau delaminasi pada material. Gelombang ultrasinic ini dibnagkitkan oleh tranducer dari bahan piezoelektri yang dapat menubah energi listrik menjadi energi getaran mekanik kemudian menjadi energi listrik lagi.

Radiographic Inspection

Pemeriksaan radiografi dan X-ray merupakan metode NDT yang mendeteksi cacat dalam bahan oleh penetrasi foton energi tinggi. Jumlah radiasi diserap kemudian dapat diukur untuk menentukan ketebalan atau komposisi bahan.

The Perfect Job Interview in 8 Simple Steps, by Jeff Haden

Here are eight practical ways to shine:

1. Be likable. Obvious? And critical. Making a great first impression and establishing a real connection is everything. Smile, make eye contact, be enthusiastic, sit forward in your chair, use the interviewer's name.... Be yourself, but be the best version of yourself you possibly can. We all want to work with people we like and who like us. Use that basic fact to your advantage. Few candidates do.
2. Never start the interview by saying you want the job. Why? Because you don't know yet. False commitment is, well, false. Instead...
3. Ask questions about what really matters to you. (Here are five questions great job candidates ask.) Focus on making sure the job is a good fit: Who you will work with, who you will report to, the scope of responsibilities, etc. Interviews should always be two-way, and interviewers respond positively to people as eager as they are to find the right fit. Plus there's really no other way to know you want the job. And don't be afraid to ask several questions. As long as you don't take completely take over, the interviewer will enjoy and remember a nice change of pace.
4. Set a hook. A sad truth of interviewing is that later we often don't remember a tremendous amount about you -- especially if we've interviewed a number of candidates for the same position. Later we might refer to you as, "The guy with the alligator briefcase," or, "The lady who did a Tough Mudder," or, "The guy who grew up in Panama." Sometimes you may be identified by hooks, so use that to your advantage. Your hook could be clothing (within reason), or an outside interest, or an unusual fact about your upbringing or career. Hooks make you memorable and create an anchor for interviewers to remember you by -- and being memorable is everything.
5. Know what you can offer immediately. Researching the company is a given; go a step farther and find a way you can hit the ground running or contribute to a critical area. If you have a specific technical skill, show how it can be leveraged immediately. But don't say, for example, "I would love to be in charge of revamping your social media marketing." One, that's fairly presumptuous, and two, someone may already be in charge. Instead, share details regarding your skills and say you would love to work with that team. If there is no team, great -- you may be put in charge. If there is a team you haven't stepped on any toes or come across as pushy. Just think about what makes you special and show the benefits to the company. The interviewer will be smart enough to recognize how the project you bring can be used.
6. Don't create negative sound bites. Interviewers will only remember a few sound bites, especially negative ones. If you've never been in charge of training, don't say, "I've never been in charge of training." Say, "I did not fill that specific role, but I have trained dozens of new hires and created several training guides." Basically, never say, "I can't," or "I haven't," or "I don't." Share applicable experience and find the positives in what you have done. No matter what the subject, be positive: Even your worst mistake can be your best learning experience.
7. Ask for the job based on facts. By the end of the interview you should have a good sense of whether you want the job. If you need more information, say so. Otherwiseuse your sales skills and ask for the job. (Don't worry; we like when you ask.) Focus on specific aspects of the job: Explain you work best with teams, or thrive in unsupervised roles, or get energized by frequent travel.... Ask for the job and use facts to prove you want it -- and deserve it.
8. Reinforce a connection with your follow-up. Email follow-ups are fine; handwritten notes are better; following up based on something you learned during the interview is best: An email including additional information you were asked to provide, or a link to a subject you discussed (whether business or personal.) The better the interview -- and more closely you listened -- the easier it will be to think of ways you can make following up seem natural and unforced. And make sure you say thanks -- never underestimate the power of gratitude.

Engineering Machine Shop Safety Handout

The Basic Rules


1. Never work alone.
At least two adults must be in the shop when power tools are being used.
2. Never work when you are impaired.
This includes when you are too tired, stressed or hurried to work carefully.
3. If you cannot do a job safely in this shop, don’t do it.
There are limits to what we can build here.
4. Always wear closed-toe shoes in the shop.
Tools, chips and fixtures are sharp, and often hot. Shoes will help protect your feet from
injury. Leather shoes are preferred when welding.
5. Eye protection is essential. Always wear safety glasses when working or cleaning
tools.
Prescription glasses sold in the US with plastic lenses meet ANSI Standard Z87.1 for
safety.
6. Remove or secure anything that might get caught in moving machinery.
Rings, necklaces, long hair and loose clothes that get caught in tools can drag you along.
7. Keep your hands away from sharp tools.
Make sure that nothing that you do will cause you to be cut.
8. Dust, chemicals and smoke can be dangerous – work in well-ventilated areas,
minimize contamination and use appropriate protective equipment.
The safety equipment cabinet is on the patio.
9. If you’re unsure about the safe operation of a tool or any aspect of a job – ask for
help!
Have shop staff check you out on a tool the first time you use one with which
you are unfamiliar.
10. Clean up after yourself.
Before you leave the shop each day all tools must be returned to the toolbox, the machine
cleaned and wiped down and the floor swept. Leave 10-15 minutes for cleanup.


Drill Press Safety Guidelines

1. Run drill at correct RPM for diameter of drill bit and material. Ask shop personnel for the
correct RPM.
2. Always hold work in a vise or clamp to the drill table.
3. Use a correctly ground drill bit for the material being drilled. Shop personnel can help
select the correct bit.
4. Use the proper cutting fluid for the material being drilled. Ask the shop staff about the
appropriate fluid for the material you are machining.
5. Remove chips with a brush, never by hand.
6. Ease up on drilling pressure as the drill starts to break through the bottom of the material.
7. Don't use a dull or cracked drill. Inspect the drill before using.
8. Don't drill with too much pressure.
9. Always try to support part on parallels or a backing board when drilling thru material.
10. Never place taper shank tools such as large diameter drills or tapered shank reamers in a
drill chuck. Only straight shank tools such as standard drills can be clamped in chucks.
11. Always clean drill shank and/or drill sleeve, and, spindle hole before mounting.
12. Remove taper shank tools from spindle or sleeve with a drill drift and hammer.
13. Never try to loosen the drill chuck while the power is on.
14. Lower the drill spindle close to the table when releasing the drill chuck or taper shank
drill to reduce the chance of damage should they fall onto the table.
15. Never clean a machine while it is in motion!!
16. If the drill binds in a hole, stop the machine and turn the spindle backwards by hand to
release the bit.
17. When drilling a deep hole withdraw the drill bit frequently to clear chips and
lubricate the bit.
18. Always remove the drill chuck key, or, the drill drift from the spindle immediately after
using it.
19. Wear safety eye protection while drilling.
20. Let the spindle stop of its own accord after turning the power off. Never try to stop the
spindle with your hand.
21. Plexiglass and other brittle plastics can be difficult to drill. Ask the shop superintendent
for advice on drill and coolant selection when drilling these materials.


Lathe Safety Guidelines

1. Make sure that the chuck, driveplate, or, faceplate is securely tightened onto the lathe
spindle.
2. When removing the chuck, driveplate, or faceplate do not use machine power.
3. When installing the chuck, driveplate, or faceplate do not use machine power.
4. Move the tool bit a safe distance from the collet or chuck when inserting or removing
work.
5. Don't run the machine faster than the proper cutting speed – consult a speed and feed
table to determine the best speed.
6. In setting up the tool holder place it to the left side of the compound slide to prevent the
compound slide from running into the chuck or spindle attachments.
7. Always clamp the toolbit as short as possible in the toolholder to prevent it from breaking
or chattering.
8. Always make sure that the toolbit is sharp and has the proper clearance. Ask for
assistance making adjustments.
9. If any filing is done on work revolving in the lathe, file left handed to prevent slipping
into the chuck. Never use a file without a handle.
10. If work is turned between centers, make sure that proper adjustment is made between
centers and that the tailstock is locked in place.
11. If work is being turned between centers and expands due to heat generated from cutting,
readjust centers to avoid excessive friction.
12. Do not grasp or touch chips or turnings with your fingers, but get rid of them using a
blunt instrument. It is safer to turn off the lathe before clearing chips then to leave it
running.
13. Set the toolbit on the centerline of your work to prevent work from climbing over tool or
cutting above center and dragging.
14. Don't cut work completely through when turning between centers.
15. Remove chuck key from chuck immediately after using.
16. Turn chuck or faceplate through by hand before turning on the power to be sure there is
no binding or clearance problem.
17. Stop the machine before taking measurements.
18. Before cleaning the lathe remove tools from the tool post and tailstock.


Milling Machine Safety Guidelines

1. Work must be clamped securely in a vise and vise clamped tightly to the table, or, work
must be clamped securely to the table.
2. Do not take climb milling cuts on the shop’s mills unless instructed to do so.
3. Make sure cutter is rotating in the proper direction before cutting material.
4. Before running machine the spindle should be rotated by hand to make sure it is clear for
cutting.
5. Make sure the power is off before changing cutters.
6. Always use the proper cutting fluid for the material being cut.
7. Never run the machine faster than the correct cutting speed.
8. Make sure that the machine is fully stopped before taking any measurements.
9. Always use cutters which are sharp and in good condition.
10. Don't place anything on the milling machine table such as wrenches, hammers, or tools.
11. Always stay at the machine while it is running.
12. Don't take too heavy a cut or use too rapid a feed.
13. Remove the collet tightening wrench immediately after using it.
14. If at all feasible rig a guard or shield to prevent chips from hitting other people.
15. Use the milling machine spindle brake to stop the spindle after the power has been turned
off.
16. Before cleaning the mill remove cutting tools from the spindle to avoid cutting yourself.

Band Saw Safety Guidelines

1. The upper guide and guard should be set as close to the work as possible, at least within
1/4 inch.
2. If the band breaks, immediately shut off the power and stand clear until the machine has
stopped.
3. Examine blade before installing to see if it is cracked, do not install a cracked blade.
4. Use the proper pitch blade for the thickness of the material to be cut. There should be at
least 2 teeth in the material when cutting aluminum, and three teeth when cutting steel.
5. Check the speed table for the material that you are cutting. Do not run the band saw
too fast or the blade will wear out quickly.
6. If the saw stalls in a cut, turn the power off and reverse the blade by hand to free it.

Guidelines For Gas Metal Arc Welding (GMAW)

Gas Metal Arc Welding (GMAW) is a welding process which joins metals by heating the metals to their melting point with an electric arc. The arc is between a continuous, consumable electrode wire and the metal being welded. The arc is shielded from contaminants in the atmosphere by a shielding gas.
GMAW can be done in three different ways:
Semiautomatic Welding - equipment controls only the electrode wire feeding. Movement of welding gun is controlled by hand. This may be called hand-held welding.
Machine Welding - uses a gun that is connected to a manipulator of some kind (not hand-held). An operator has to constantly set and adjust controls that move the manipulator.
Automatic Welding - uses equipment which welds without the constant adjusting of controls by a welder or operator. On some equipment, automatic sensing devices control the correct gun alignment in a weld joint. Basic equipment for a typical GMAW semiautomatic setup: Welding Power Source - provides welding power. Wire Feeders (Constant Speed And Voltage-Sensing) - controls supply of wire to welding gun. Constant Speed Feeder - Used only with a constant voltage (CV) power source. This type of feeder has a control cable that will connect to the power source. The control cable supplies power to the feeder and allows the capability of remote voltage control with certain power source/feeder combinations. The wire feed speed (WFS) is set on the feeder and will always be constant for a given preset value. Voltage-Sensing Feeder - Can be used with either a constant voltage (CV) or constant current (CC) - direct current (DC) power source. This type of feeder is powered off of the arc voltage and does not have a control cord. When set to (CV), the feeder is similar to a constant speed feeder. When set to (CC), the wire feed speed depends on the voltage present. The feeder changes the wire feed speed as the voltage changes. A voltage sensing feeder does not have the capability of remote voltage control. Supply of Electrode Wire. Welding Gun - delivers electrode wire and shielding gas to the weld puddle. Shielding Gas Cylinder - provides a supply of shielding gas to the arc.

1 Constant Voltage (CV)
Welding Power Source
2 Contactor Control/Power Cord
3 Weld Cable To Feeder
4 Ground Cable To Workpiece
5 Workpiece
6 Welding Gun
7 Constant Speed Wire Feeder
8 Electrode Wire
9 Gas Hose
10 Shielding Gas Cylinder

AutoCAD® 2010 Tutorial - "Creating a Surface of Irregular Shape"

.....sambungan




6. In the command prompt area, the message “Specify
fourth point or [invisible]
face>:” is displayed. Pick the corner below the last
selected corner as shown.

7. On your own, repeat the zigzagging

pattern to define polygons until all

corners of the inclined surface have been

selected and additional polygons are

created as shown in the figure. Note that

the last polygon we created is a threesided

polygon.

8. In the Visual Styles toolbar, click on the 3D Hidden icon
to display the model with hidden lines removed. Note that
the edges of the polygons are displayed as shown.


9. On your own, examine
the model by selecting
the different Visual
Styles.


10. Rest the Visual Styles toolbar to 2D
Wireframe, the default AutoCAD display
mode.


Using the Invisible Edge Option



• The Invisible Edge option is used to turn off the display of selected edges and
therefore allow the adjacent polygons, created by the 3D Face command, to
appear as being joined together.

PROACTIVE MAINTENANCE

Abstract:

Toyota as an automotive market leader in Indonesia with 30% market share, always strives to do Kaizen “continuous improvement” on each of their activity. One of the realization kaizen in manufacturing side which becomes Proactive Maintenance Method to make no breakdown machine on production time is zero breakdown activity. This activity is nearly based on TPM concepts but many modification strategies have conduct to reach its goal. First thing that revolutionary is Mieruka concept, how to know the process and machine problem using coverless strategy.
To get commitment from production side who become the owner of machine, PM-Production Maintenance which emphasized on qualified production member knowledge transfer to others and SM-Self Maintenance which move to find the root cause of problem both productions, maintenance and engineering, also present. Senmonginou (Special skill Training) is a method to fulfill maintenance & production skill to solve machine fault and abnormality.
Others new strategies that become proactive maintenance method will described clearly in this paper. Examples of implementation programs in TMMIN (Toyota Motor Manufacturing Indonesia) will be presented.

Proactive Maintenance Concepts

Based on the first terminology of proactive maintenance, it is stated that proactive maintenance is a maintenance method that commissions corrective actions aimed at the sources of failure. It is proposed to extend the life of mechanical machinery as opposed to
1) making repairs when often nothing is broken,
2) accommodating failure as routine and normal, and
3) preempting crisis failure maintenance
But, when we generally discuss about proactive maintenance, broader aspect could be included just like when we have a program that assists in scheduling preventive maintenance at the recommended intervals and monitors when those tasks are performed, it becomes proactive. We are also proactive when we repair and replace components before they are getting failure. Training plant operators is also programmed to recognize components when they are showing signs of failure and having procedures to report those are also proactive2.

TPM as Windows to Reach Zero Breakdowns

One of the TPM (Total Productive Maintenance) objectives is reducing cost. An overall production cost, including how cost-saving happened by finding the root causes of machine worn out and failure then implement a precise countermeasure is also the proactive one. If we study in a short time to reach zero breakdowns, preventive maintenance cannot eliminate breakdown alone.
According to the principles of reliability engineering, the causes of equipment change with the passage of time refer to bathtub curve (figure 1) . The causes of early period failure are design and manufacturing errors. To combat them, the engineering design must conduct test runs at the earliest stage. Furthermore, maintainability improvement should be pursued to discover and treat weakness design and manufacturing. Accidental failures are caused primarily by operation errors, so the most effective countermeasure is to ensure that operators use equipment properly.
Wear-out failures are due to the limited natural life span of equipment parts. Equipment life can be extended by preventive maintenance and by maintainability improvement (through changes in design). This will reduce the wear-out failure rate.

Figure 1. Bathtub curve

Maintenance prevention is an effective countermeasure for all three types of breakdown. A maintenance-free equipment design must be incorporated at the planning/design stage to prevent early period, accidental, and wear-out failures.
Depicted on that illustration, preventive maintenance alone cannot eliminate breakdowns. All departments cooperated to do TPM, and maintenance as well as engineering and production must be involved in the breakdowns elimination. Based on effort to eliminate failures, it could be categorized into five countermeasures:

1. Maintaining well-regulated basic conditions (cleaning, lubricating, and tightening)
2. Adhering to proper operating procedures
3. Restoring deterioration
4. Improving weakness in design
5. Improving operation and maintenance skills


Figure 2 illustrates the relation between these five countermeasures. As this figure illustrates, breakdowns can be eliminated by carrying out simple procedures in a simple manner and its
aim to be zero breakdown. In another words, activity done to reach zero breakdown which involving all departments to gain no breakdown machine is derivative from TPM activity. And this activity also based on pillars of TPM which prior on jishu hozen or autonomous maintenance, kobetsu kaizen or conduct continuous improvement, planned maintenance, honshitsu hozen or quality maintenance and training maintenance which also motivate to bring strategic and systematic ways to step ahead towards breakdown elimination. This concept could be mathematic as:

......... Zero Breakdown Machine (second)…………. (eq.1)


It means that when TPM was running well with third stage implementation; preparation, implementation and stabilization on its company system especially on its maintenance side the ideal machine condition could be achieved. And the business supply chain also affected both on its upper and downstream.

On the next page, implementation of zero breakdowns activities in TMMIN (Toyota Motor Manufacturing Indonesia) will be described and illustrated, the method and sampling taken from its engine plant. We refer to TMMIN Ltd. Because this company has been applied the very well known methods: Total Productive Maintenance to achieve zero breakdowns in their plant. However, The TPM here is the unique one because they also implemented Kaizen and Mieruka system so we called it as “Proactive Maintenance”, a new approach to Maintenance Word Methods.

Figure 2. Relationships between breakdown countermeasures



........................... 01 ................................

Inilah Konsep Sepeda Motor Listrik Masa Depan

KompasOtomotif - Kampanye kendaraan ramah lingkungan tidak hanya pada mobil saja, tetapi para produsen sepeda motor dunia juga sudah mulai menyiapkan konsep andalannya. Menariknya,  sepeda motor bertenaga listrik ini, didesain dengan tingkat mobilitas dan kinerja tinggi di masa depan. Inilah desain sepeda motor listrik tersebut;

1. Frog eBike 2012 (Frog Design)

Frog eBike ini merupakan desain yang bertujuan untuk membunuh banyak desain tradisional dari bentuk sepeda motor konvesional. Motor listrik yang menggantikan mesin pembakarannya, dibuat seminimal mungkin dan merampingkan komposisi sepeda motor itu. Rumah baterai akan dipasang pada bagian bawah sasis dan posisi itu akan membantu menurunkan pusat gravitasi. Komponen lain yang akan dilengkapi pada Frog eBike ini termasuk panel instrumen OLED digital, kemudi fly-by-wire dan helm dengan pendeteksi retina, serta heads-up display.

2. Honda Oree (Nike Albertus & Andre Look)

Inilah karya mahasiswa Jerman, Andre Look dan Nike Albertus. Sepeda motor ini paket baterai sport dan motor listrik, yang ditempatkan di tepi powerplant. Motor listrik tersebut dapat menyemburkan tenaga 91 PS dan torsi 169 Nm, sehingga kuda besi ini dapat berlari dengan kecepatan maksimal 190 kpj. Oree juga mengambil sedikit desain naked bike dengan suspensi yang terbuka.

3. AER Racing (Andre Federico Look)

AER akan menjadi salah satu konsep dengan tenaga besar, karena memakai 4 motor listrik bertenaga 143,5 kW. Pada roda depan dibekali satu mesin listrik kecil untuk menggunakan kembali energi yang ada saat pengereman. Lantas, 4 motor listrik yang masing-masing berbobot 4,5 kg akan dipakai untuk memberikan akselerasi lebih cepat.

4. BMW E 100R (Mika Mahonen)

Desain yang satu ini dirancang sebagai sepeda motor dengan nol emisi dengan biaya rendah. Karena itu, desain yang ditampilkan sederhana, mengandalkan rangka yang ringan dan mesin kuat. BMW E 100R mampu menghasilkan tenaga hingga 108 PS dan torsi 131 Nm, yang energinya disuplai oleh sebuah baterai pada rangkanya.

5. VertiGo (Maarten Timmer)

Desain sepeda motor listrik Timmer mengambil bentuk sport, yang menjanjikan torsi tinggi, akselerasi cepat, emisi rendah dan jarak berkendara 100 sampai 150 km. Memang secara desain VertiGo ini tidak jauh berbeda dengan motor sport konvensional, tapi dipercaya kuda besi ini dapat memberikan torsi instan.

Mesin Karburator VS Injeksi

Dikenal dengan teknologi Direct Fuel Injection, teknologi ini merupakan yang terbaru dalam hal pengkabutan BBM pada mesin bensin. Cara kerjanya juga serupa dengan mesin diesel, di mana bahan bakar diinjeksikan melalui jalur common rail langsung ke dalam silinder. Dan teknologi ini memang relatif lebih mahal dibanding sistem karburator.

Dengan penggunaan teknologi ini bahan bakar tentu lebih lebih efisien, output daya juga bisa jadi lebih tinggi dan yang terpenting emisi gas buangnya lebih rendah sehingga lingkungan lebih bersih.

Penggunaan bahan bakar dan timing injeksi bisa tepat dikendalikan sesuai dengan kondisi beban kendaraan. Kecepatan mesin ditentukan oleh waktu pengapian dan fungsionalitas injeksi bahan bakar dikontrol secara cermat oleh ECU (unit control mesin).

Teknologi injeksi juga ada yang bernama Port Fuel Injection, perangkat ini mungkin tipe yang paling umum dari sistem injeksi bahan bakar yang bisa ditemukan di seluruh dunia. Bahan Bakar disuntikkan pada setiap pengambilan port, biasanya terletak di kepala silinder dan intake manifold.

Desain yang melekat dari jenis sistem injeksi bahan bakar memungkinkan untuk lebih sedikit fleksibilitas dalam desain intake-manifold. Sehingga membuat pernafasan mesin membaik, dalam hal ini memungkinkan untuk modifikasi dengan perangkat turbo untuk menghasilkan tenaga lebih besar.

Teknologi injeksi selanjutnya ada Throttle Body Injection, di mana teknologi ini yang paling sering digunakan dalam desain untuk mesin karburator pada umumnya. Nosel injektor yang menyuntikkan bahan bakar berada di atas klep throttle. Campuran bahan bakar dan udara kemudian dibawa melalui saluran intake ke ruang pembakaran.

Sistem injeksi jenis ini ditemukan antara tahun 1980-1995. Keuntungan terbesar dari sistem ini adalah bahwa hal itu relatif rendah biaya dan banyak komponen pendukung seperti intake manifold, filter udara, dan saluran bahan bakar routing yang dapat digunakan kembali.

Jadi kesimpulan dari kedua teknologi ini adalah sistem injeksi lebih baik dari sistem karburator. Walau harga lebih mahal, teknologi ini memiliki masa depan yang lebih baik untuk lingkungan agar lebih hijau.

Apalagi mengingat kebijakan pemerintah mengenai pembatasan BBM subsidi, serta semakin banyaknya kendaraan terbaru bermunculan dengan teknologi mesin injeksi. Sudah selayaknya konsep pemahaman kita berubah tentang penggunaan bahan bakar yang tepat sesuai dengan perkembangan teknologi.

Sebab penggunaan teknologi injeksi pada suatu kendaraan itu diharapkan mampu menghasilkan pengkabutan bahan bakar lebih baik dari karburator dengan penggunaan BBM yang memiliki kadar timbal lebih sedikit atau memiliki nilai oktan lebih besar.

Jika pemahaman ini kita terapkan dengan baik, maka perawatan kendaraan injeksi jauh lebih mudah dan bisa jadi lebih murah dibanding kendaraan menggunakan karburator.