What is wrench?

A wrench is represented as a machine tool having a broad opening, and its objective is to turn a bolt head or any particular nut to tighten or loosen. Some of the materials used to prepare wrenches are vanadium as well as chromium through the forging process. Initially, the steel rod is divided into multiple parts and then placed those parts in a heating coil in order to melt.

The following is the basic structure of a wrench.

A wrench with its profile, head and shaft is shown in the diagram. The middle part of the wrench is known as shaft.

What are various types of wrenches?

The following are some of the common types of wrenches.

  • Adjustable wrench (Monkey wrench)
  • Allen wrench
  • Box-ended wrench
  • Combination wrench
  • Crowfoot wrench
  • Impact wrench
  • Lug wrench

Adjustable wrench

Adjustable wrenches are one of the most typical wrenches used in the automobile industry. It contains a helical screw at the free end, which helps in the opening and closing of the wrench. An adjustable wrench gives more gripping power without rounding fasteners.

The illustration below expressed an adjustable wrench.

An example of adjustable wrench is shown in the illustration. Also, the various parts of this wrench is labelled.
Adjustable wrench

Allen wrench

Allen wrench is referred as L shaped wrench that can be used as a handle for bolts and fasteners. Some of the characteristics of Allen wrenches are strength, easy to apply, and utility. The smallest size available for the Allen key is 0.71 millimeters in the wrench set.

Box-ended wrench

Box-ended wrench contains a closed ring at each end which is placed significantly higher on one side and lower on another side. These types of the wrench are required to slip around the end of the nut, and it is expensive as compared to other types of wrenches. Generally, in most places, twelve-point variants of a box-ended wrench are majorly employed.

Combination wrench

A combination wrench is a type of wrench that is composed of a covered loop at one end and a U shape at the other end. The combination wrench can be used as an alternative for the box-ended or open-ended wrench. Some of the applications and benefits of a combination wrench are better torque, easy removal of tight spots, and multi-purpose wrench. The smallest metric size of this type of wrench is 6 millimeters.

Crowfoot wrench

The Crowfoot wrench has a U-shaped single head that does not contain any handle or grip. In order to manage deeper located bolts or tight spaces on a specific body, a crowfoot wrench is applied. The durability of a high polished crowfoot wrench is high, and storage of a wrench set is quite easy.

Impact wrench

Impact wrenches can be classified into two parts which are listed below.

  • Cordless impact wrenches
  • Air impact wrenches

Cordless impact wrenches are heavier than air impact wrenches because of their cordless prototype, but the convenience factor is more for cordless wrenches. An air wrench is a simple and affordable tool, whereas a cordless wrench demands high costs. A brushless motor is used in a cordless wrench, and an air compressor is used in an air impact wrench.

Lug wrench

The lug wrench is designed in an X frame, with four sockets at each end of the two rods. These are mostly used in vehicles' wheels for better convenience. The additional length in this tool provides better torque in contraction or loosening. Also, in some lug wrenches, the spring locking mechanism is used for gaining extra length.

Other various types of wrenches

The below illustration describes various types of wrenches.

The illustration classifies various types of wrenches. Four different wrenches are used.
Different types of wrench

Some of the other varieties of wrench used are listed below.

  • Alligator wrench
  • Armorer's wrench
  • Basin wrench
  • Bung wrench
  • Drum key
  • Fire hydrant wrench
  • Hammer wrench

Alligator wrench

An alligator wrench can be helpful in tuning different types of tubes made of iron or other materials. It is called an alligator because its top jaw is jagged, and the bottom one is smooth. These sorts of wrenches are majorly designed for square-shaped heads of nuts.

Armorer's wrench

An armorer's wrench is a C-shaped wrench, having jagged jaws at the head. It is primarily used in several types of armors for repair as well as maintenance. The jaws of the wrench are not as strong as the alligator wrench, so there is the possibility of breakage while releasing a certain nut.

Basin wrench

The basin wrench has a T-type structure with a long handle, where at one end, two asymmetrical jaws are placed. In our daily life, it can be used as a plumbing device because it is utilized for tightening or loosening fixtures at washbasins and washrooms.

Bung wrench

The bung wrench is referred to as a socket type wrench. It plays a vital role in releasing metal caps or fiber caps from drums, barrels, or huge bottles. Generally, the bung wrench is made using aluminum and bronze or copper-beryllium.

Drum key

A drum key is a kind of socket wrench with T type shape. The size of the handle used in this wrench is long, which provides higher torque. It can be applied for tuning purposes in musical instruments like drum, throne, tambourine, toms drum, and many others.

Fire hydrant wrench

The fire hydrant wrench is designed in pentagonal shape for opening or closing of valves in fire hydrants. It consists of a long shaft, which helps to generate more torque while applying the wrench. Also, in the opening of gas enclosures, dry risers, doors knobs, and other hydrant wrench is used.

Hammer wrench

A hammer wrench contains closed-loop teeth head at one end. In this type of wrench, a hammer can be used to apply a high amount of force. One of the essential purposes of a hammer wrench is to tighten fasteners and fittings of the different-sized flange.

Advantages of wrench and wrench set

  • Wrenches are utilized in daily life as plumbing instruments.
  • On flat surfaces, wrenches are used on nuts or bolts.
  • Wrenches are adjustable with a different sized opening of pipes and other tubes.
  • Many varieties of wrenches produce torque as required, which helps in critical situations.
  • Ratcheting wrench set avoids resetting or removing like combination wrench.
  • Wrenches and ratcheting wrench sets are cheaply available.
  • Maintenance is low.

Disadvantages of wrench and wrench set

  • Wrenches are harmful to the operator and cause injury.
  • It is less stable as compared to fixed-size wrenches.
  • Wrenches cause damage to fasteners or bolts while tightening or loosening.
  • Slip is one of the most common defects of wenches.
  • Sometimes, a wrench of exact type is hard to find.
  • Ratcheting wrench sets are expensive.
  • The head's large diameter is a concern for ratcheting wrench sets.

Common Mistakes

  • Always use quality wrenches and check before applying. Avoiding this may cause injury to the person.
  • Proper size of wrench should be employed on nuts or bolts.
  • One of the common mistake is to add leverage with other components.
  • Operators don't check the wrench before applying force, and this can cause serious harm to him.

Context and Application

The topic wrenches is very much significant in the several professional exams and courses for undergraduate, Diploma level, graduate, postgraduate. For example:

  • Bachelors of Science in Physics
  • Bachelors of Technology in Mechanical Engineering
  • Bachelors of Technology in Civil Engineering
  • Masters in Technology in Mechanical Engineering
  • Doctor of Philosophy in Mechanical Engineering
  • Diploma in Mechanical Engineering
  • Ratcheting wrench set
  • Wrench set box
  • Ratcheting box wrench
  • Ratcheting mechanism
  • Ratcheting spanner
  • Wrench set metric and standard
  • Metric wrenches
  • Combination wrench set

Practice Problems

Q1. Solymon Merrick discovered which one of the following tool?

a. Screwdriver

b. Wrench

c. Hammer

d. None of these

Correct answer: (b)

Q2. Informing a rivet head which type of hammer is used?

a. Hand hammer

b. Club hammer

c. Tack hammer

d. None of these

Correct answer: (d)

Q3. Which of the wrench is used by electricians widely?

a. Hammer wrench

b. Open-end hammer

c. Impact hammer

d. Adjustable wrench

Correct answer: (d)

Q4. In order to make a wrench, the manufacturing process used is?

a. Casting

b. Forging

c. Extrusion

d. Machining

Correct answer: (b)

Q5. Which of the element is mostly used to make a wrench?

a. Aluminium

b. Vanadium

c. Copper

d. All of these

Correct answer: (b)

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