Week 2:- BiW Fixture Basics Challenge

The project excution activity process chart show in below according to that step by step process going,

• RFQ:-A request for quote (RFQ), also known as an invitation for bid (IFB), is a process in which a company solicits select suppliers and contractors to submit price quotes and bids for the chance to fulfill certain tasks or projects. The RFQ process is especially important to businesses that need a consistent supply of a specific number of standard products.
• 1St specifcation meeting:- In meeting find how much time required to design and simulation,brogth outs item and robots,process and concept of design etc discussion and offer final submission.
• PO:- Purchases order recevided then design and project plan start.
• Schedule preparation:-All project plan discuss in brifly and planning done.
• BOM preparation:- All bill of material prepared and orded.
• Design Concept:- All weding station and which station what process happens explain and send to customer approval.
• Customer approval:- All conecpts approval done then design start and design finsih and release design.
• Detailing and DWG:- after finish design dwg to be relased.

Tyes of joining process:-

GMAW

GMAW is also known as metal inert gas (MIG) welding in which an external gas, such as argon, helium, carbon dioxide, argon + oxygen, and other gas mixtures, is used as a shielding gas. Consumable electrode wire, having the same or approximate chemical composition to that of parent metal, is continuously fed from a spool to the arc zone. The arc from the welding parameters (voltage and current) heats and melts the samples’ edges and the filler wire. The fused filler metal is supplied to the surface of the workpiece, fills the weld pools, and forms the joint between the workpieces similarly or dissimilarly. The overall process in GMAW is described as a semi-automatic method because of the automatic feeding of the filler rod while the welder controls only the position and speed of the torch. GMAW can weld almost all metals and alloys, aluminum alloys, and stainless steel.

GTAW

GTAW is also known as tungsten inert gas (TIG) welding, in which heat from an electric arc is used. The arc sparks between a tungsten non-consumable electrode and the workpiece. The molten pool is shielded by an inert gas such as argon, helium, and nitrogen. The shielding gas prevents the molten pool from atmospheric contamination. The heat produced by the arc melts the samples’ edges. The filler rod can be used if required, especially in welding aluminum. GTAW produces a high quality weld of most metals because it does not use flux. An externally supplied shielding gas is necessary because of high temperatures involved to prevent metal from oxidation. Direct current is typically used, and its polarity is important as this welding method still uses current and voltage as critical parameters. Given that the tungsten electrode is not consumed during welding, a stable and constant arc is preserved at a constant current level. The filler metals used are usually similar to the parent metals to be welded, without using flux. The shielding gas used is normally argon or helium (or a mixture of gases). GTAW is used for a wide variety of metals and applications. Metals that usually can be welded by GTAW are aluminum, magnesium, titanium, and copper and its alloy. The tungsten electrode is usually in contact with a water-cooled copper tube (contact tube), which is connected to the welding cable from the terminals. Both the weld current and electrode must be cooled to avoid overheating during welding.

RESISTANCE WELDING:-

Resistance welding, sometimes called electric resistance welding (ERW),is a process by which metals can be joined together by applying pressure and conducting a strong electric current through the metal combination to heat up the welding joint and melt the metals, forging them together.

Working process:-

Resistance welding is generally used to join two plain metal work pieces together. An electric current is delivered to the metal sheets (or any work pieces being joined) through weld electrodes which apply force to the sheets. This force is then converted to heat. The heat is generated so that it melts the metal at the point where they join – the point of ‘resistance’ between the faying surfaces. The electrode then extracts heat from the molten weld area which forms a weld nugget at the point where it solidifies. A force is applied before, during and after a current is applied, which confines the contact area.

TYPES:-

1. Resistance Spot Welding

Resistance spot welding has been used extensively in the automotive industry for the joining of steel and in the aerospace industry for airframe components made from aluminium alloys. It is one of the oldest and simplest forms of resistance welding, in which a weld nugget is produced by passing an electric current between the two metal components whilst they are held together between electrodes, typically made from copper-based alloys due to its superior conductive properties.

2. Resistance Seam Welding

Resistance seam welding is a variation of the standard spot welding form, however instead of spot one nugget, a series of overlapping nuggets is produced. This is usually done by replacing the conventional spot welding electrodes with wheels, which turn as the parts are fed between them. The process thus produces a continuous welded seam rather than a single spot. Seam welding is often used in the production of thin sheet, leak-tight containers such as fuel tanks, and is generally unsuitable for welding aluminium.

3. Resistance Projection Welding

Resistance projection welding is a form of resistance welding where the electricity, force, and weld time are concentrated on raised ‘projections’ across the surface. Projection welding is generally used for welds using thicker materials than the thinner metal pieces that spot welding is usually required for, and often not metals. It is used primarily in the electrical, automotive and construction industries.

4. Resistance Butt Welding

Resistance butt welding is a process in which the two components of similar cross section can be joined together in one operation that takes place simultaneously across the entirety of the affected object, rather than just in small spots. The welding application of butt welding is often in wires and rods with small diameter measurements, generally up to about 16mm diameter.

Advantages

• Similar and dissimilar metals are capable of being welded
• Highly automated
• Efficient with high production rate and high welding rate
• Cost-effective.
• Environment-friendly, produces little waste or pollution.
• No need for filler metal or extraneous materials such as rods, fluxes, inert gasses, oxygen, or acetylene are required.

3-2 1 principle

In the automotive tooling industry you will hardly get any designer who does not know 3-2-1 principle.

If the any part e.g steel block to be machined using milling machine;1st question the milling machine operator will think how I will hold the part.

Operator will use the various clamp to hold the job to withstand the cutting forces.

Ideally 3-2-1 principle is used to locate the job .

What 3 means ?

What 2 mean ?

What 1 mean?

Simple they represent the directions.

Any part which has to be fixed during welding or during machining process has to be fixed. with this principle. Every object is having 6 degrees of freedom.

1) Translational movement along X -axis

2) Translational movement along Y-axis

3) Translational movement along Z-Axis

4) Rotational movement along X -axis

5) Rotational movement along Y-axis

6) Rotational movement along Z-Axis