TORQUE TABLE

 Dear Readers,

Based on my previous posts you may familiar with grades of bolt, torque of bolt, torque calculations and slip factors. However it is a real challenge in construction industry to determine the torque for bolts. Technically it is based on the applications. Some times client mentioned in drawings or you may get it from technical specifications but most of the times both are missed out. Given below is an ideal chart. This is one of my rare collections. Hope it will be very useful to all engineers.

 

For More Details about Torque Click my Previous Post Torque

For More Details about Grade of Bolts Click my Previous Post Grade

For More Details about Torque Calculations Click Calculation

For More Details about Slip Factor/Nut Factor Click Nut Factor

Stick Welding Tips for Beginners

Dear Readers,

Due to COVID-19, past two months there is no posts.

Though Stick Welding is one of the most common forms of arc welding. To be an effective stick welder, one requires higher skill level and mastery of certain techniques. Here are three important things that a beginner needs to focus on.

1). Power or Current Setting

2). Length of Arc

3). Angle of Travel

4). Manipulation of Electrodes

5). Speed of Travel.

Let us discuss in details

Power or Current Setting

The welding machine allows you to set the current as DC positive, DC negative or AC. Which current you select, solely depends on the electrode you are using. Look for the current specifications mentioned on the electrode packaging. It is advisable to change the applied current, 5 amps at a time, till you reach the optimum current setting required for the operation. If the set current is lower, the electrode will appear sticky whereas, if you apply higher current, the electrode may get scorched.

Length of the Arc

While the fact is that the arc length changes with the change of the electrodes, the general rule of thumb is that the length of the arc should not be greater than the diameter of the metal part of the electrode. If the arc is too short, then the electrode may stick to the metal surface due to low voltage. On the other hand, a larger arc may cause spatter and undercuts.

Angle of Electrodes

The ideal way to hold the electrodes, depends on whether you need to weld on a flat horizontal surface, or on a vertical surface. When welding on a horizontal surface, keep the electrode at an angle of 15 degrees towards the direction of movement. When welding on a vertical surface, tilt it at the same angle away from the angle of movement.

Manipulation of Electrodes

Manipulation of electrodes is nothing but the way the electrodes are moved to produce different results. This is a skill that you can acquire over time, through practice and by observing experienced welders at work. For example, you can manipulate the electrode side-to-side to form a step pattern. When welding along a vertical surface, pay special attention to the sides of the joints to prevent any error.

Speed of Travel

A useful tip to find the ideal speed of moving the electrode further, is to form a weld pool (a pool of molten metal) and then drive the electrodes at a speed such that your electrodes are always at the leading one-third area of the weld pool. If you move very slowly, it will result in "cold-lap" and poor alignment. On the other hand, moving extremely fast can cause an undercut.

For more details about stick welding , please click here

Hope you have enjoyed this post and it is useful for the beginners. 

Difference Between Steel Sheet vs Steel Plate vs Steel Foil

Dear Readers,

Difference Between Steel Sheet vs Steel Plate vs Steel Foils are as follows. Thickness is a main criteria for all

Metal Foil

Metal foil is a very thin sheet of metal that has been hammered or rolled flat. Metal foils can be made from any type of metal, although the most commonly found foils are aluminum foil and gold foil. Aluminum foil typically has a thickness of .03mm, although any sheet of metal with a thickness of less than 0.2mm is considered a foil.

Steel Sheet

Steel Sheet is any metal that is thicker than a foil and thinner than 6mm, the thickness of a metal plate. Steel Sheet is often used for building structures that do not require durability. It is also often corrugated or diamonded for additional strength without increasing weight. Corrugation is the creasing of the metal at regular intervals to form ridges, and diamonding is the addition of diamond ridges that add structure to the metal.

Steel Plate

Once the steel is more than 6mm thick it is known as steel plate. Steel Plate is used in applications where durability is more important than saving weight. It is used in automobiles where durability is required to pass crash testing.

The Difference

The only difference between sheet and plate steel is the gauge (thickness) of the metal. They both have very different uses, depending on the varying durability and weight requirements for different projects.