LEARN TO READ BOLT SPECIFICATIONS !!

A bolt is a type of threaded hardware fastener that is used to position two workpieces in specific relation to each other. Bolts come in several configurations for their application and specification variances.

Each bolt is specified with some coding in it which revels the information about that bolt such as M9X1.2X1.5 .Many metric bolts denote the use of metric measurements with an "M" at the start of the bolt designation, such as "M9x1.2x15." Metric bolts list measurements in millimeters. Besides using metric measurements, a metric bolt uses the distance between the threads rather than the thread pitch, used in American measurements, which is the number of threads per inch.

How to read these specifications:

For reading the specifications of the bolt follow these steps:

Determine the diameter of the bolt by looking at the first number. For example, if the metric bolt was M10x1.25x33, it would have a diameter of 10 millimeters.


Determine the distance between threads by looking at the second number. For example, if the metric bolt was M10x1.25x33, it would have 1.25 millimeters between threads.This is also known as pitch.


Determine the length of the metric bolt by looking at the third number. For example, if the metric bolt was M10x1.25x33, it would have a length of 33 millimeters.


Look on the bolt head for the number denoting the strength of the bolt. The bigger the number, the stronger the bolt.

Hope,you got to learn something from this article.

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BAJAJ V15 AND V12 !! WHAT IS DIFFERENCE ???

Bajaj Auto launched its first bike under the V brand in March 2016. The 150cc motorcycle with cafe racer styling, made with metal from the dismantled aircraft carrier, INS Vikrant, of the Indian Navy has become a runaway success. The V15 has recorded sales figures of 2 lakh units within eight months of its launch.

Encouraged by the response, Bajaj Auto just added a younger sibling to the V15,  the V12. At first glance, both motorcycles seem identical. Both feature the cafe racer design, removable rear cowl, and curved headlamps design. However, there are a few differences between the two V models.

Here is how the two are different from each other:

Engine: Both V models are powered by single-cylinder air-cooled DTS-i engines. However, the 149.5cc motor in the V15 generates 11.8bhp at 7,500rpm and 13Nm of torque at 5,500rpm. On the other hand, the V12's 124.5cc mill comes with an output of 10.5bhp at 7,500rpm and 11.2Nm of torque at 5,500rpm.

Suspension: The V15 is equipped with 33mm telescopic forks up front. On the other hand, the V12 gets slightly thinner 31mm forks. V12's suspension is also rated 110mm of fork travel.

Brakes: The V15 boasts of a 240mm disc brake for front tyres and 130mm drum brakes at rear. The V12 is offered without disc brakes up front. Instead it gets 130mm drum brakes for both front and rear wheels.

Tyres: While the V15 is equipped with 120/80-16 tyre at the rear and 90/90-18 tyre at front, the V12 comes with skinnier 100/90-16 rear tyre. The V15 also gets tubeless tyres while the V12 misses out on tubeless tyres, which is a very important feature.

Headlight: The V15 gets bright 55/60 W headlight that provides impressive illumination. On the other hand, the new V12 gets a 35/35 W headlamp, which is very common in other commuter motorcycles.

Dimension: The V15 measures 2044mm in length, 780mm in width and has a height of 1070mm. The V12 measures 2040mm in length, 785mm in width and 1066 in height. This means the V12's length and height are slightly less than that of the V15, while it has a bit more width. Both versions come with 165mm of ground clearance and 1315mm of wheelbase.

Price: The V15 has been priced at Rs 62,132 while the V12 costs Rs 56,283, both ex-showroom, Delhi. The difference in price is Rs 5,849. 

NOTES ON SWAGING OPERATION !!

Swaging is a metal forming process of reducing diameter of a rod or tube by forcing it into a die with the help of reciprocating blow. This plastically deforms the metal and force it to flow into die and acquires die cavity shape. The fundamental concept is similar to forging process but the difference is that it uses reciprocating die for repeated hammering, which forces the metal into die. The die cavity contain the exact shape which we want to produce on rod or tube. This process is used to form screw drivers, soldering iron tip etc.

It is a cold working process. The process takes place in two parts.In the first part of this process, a circular rod or tube is made by other metal forming processes like forging, extruding, drawing etc. This rod have exact dimension which we require in final product. Now the actual swaging process occurs.

The second part is also known as rotary swaging in which rod or work piece made by other processes is held stationary into a swaging die and a movable die rotates around it. This rotating die has some reciprocating components which allow to strike the work piece at a rate 10 – 20 stroke per second. Many blows are required to complete forming of work piece. It forms a cavity according to the die on the work piece. This process is mainly used to point the end of the work piece or convert the end into desired shape as required in screw drivers, small hand tools etc. It is also used to produce hollow drive shaft, shock absorber etc.