Wrenches

 Wrenches are used for tightening and loosening of nuts and bolts.

Types of Wrenches:-

             As there are a number of variety nuts and bolts used in industry now-a-days, so also are different type of wrenches.

Commonly used types of wrenches are

1.   Open end wrench

2.   Socket wrench

3.   Pipe wrench

4.   Monkey wrench

5.   Adjustable wrench

6.   Close end wrench

7.   Twelve point Wrench

8.   Tee-socket wrench

9.   Off-set socket wrench

10.   Allen wrench

11.   Pin Wrench

12.   Hook spanner wrench

13.   Chain pipe wrench

14.   Torque wrench

USES:-

1.Open end wrench:-

Open End Wrench

              This is most commonly used type of wrench and used where there is enough space for driving it. Both ends can be used but for two different sizes. The open end wrenches common in two different shapes they are

1.   Straight

2.   S-shaped

The s-shaped wrench is most useful where there is less space.

2.Socket wrench:-

Socket Wrench

     These wrenches have detachable parts namely, the head which fits into the blot at a shaft that fits into the head and the socket of the handle and a driving lever or handle. These wrenches are widely used in auto mobile shops, repair and assemble shops.

3.   Pipe Wrench:-

Pipe Wrench

     This wrenches is used for truning pipes, pipe fitting and round bars etc., This is widely used by plumbers mill rights, the jaws of this wrench are serrated for better grip.

4.   Monkey wrench:-

Monkey Wrench

     The jaws of this wrench move parallel to each other with the help of a screw. So that it can be used for any size of nut or bolt head with in its range. The jaws are flat so that the size of the nuts or bolts heads are not spoiled. However it is only emergency tool and not be always used in place of standard wrenches.

5.Adjustable wrench:-

Adjustable Wrench

     The jaws of this wrench are adjustable within a certain range to suit different sizes of nuts and blot heads. This differs from “monkey wrench”, in that it provides a better grip and enveloped that nut like an open end wrench. However it is an emergency tool and should not be used when a fixed type of wrench is available.

6.Close end wrench:-

Close end Wrench

         This is similar to the single end wrench but it encloses the nut fully while the single end wrench encloses partially. It is also called as box wrench or box spanner.

7.Twelve point box wrench:-

Twelve Point Box Wrench

      This wrench is also as ring spanner. Both ends can be used but usually or two different sizes of nuts. There are  Twelve notches in  the wrench head and it grips hexagonal nut at six points. This is very convenient where a small turn is required.

8.   Tee socket wrench:-

Tee Socket Wrench

       This wrench is made in the shape of the letter ‘T’  and used where a great force is required and at odd places where other wrenches do not work.

9.    Off set socket:-

Off Set Wrench

       This is just like Tee Socket wrench except that the handle            is bent at 90° to the wrench head. This is used for light duty       work.

10.                     Allen wrench:-

Allen Wrench

               This is usually called as Allen key. This is made out of hexagonal bar and used for driving Allen Screws.

11.                     Pin wrench:-

Pin Wrench

                    This is used for tightening and loosening of large diameter nuts which are having fine threads and flat surfaces. Two holes are provided on the flat surface into which the pins of the Wrench engage and turn

    

12.                     Hook spanner wrench:-

Hook Spanner Wrench

                   This spanner is used for turning large diameter nuts, which are having notches on their perifery. It is also called ‘c ’ spanner.

13.                     Chain pipe Tong:-

Chain Pipe Tong

                    This wrench is specially used to hdd pipes and bars while cutting threading detaching them from their joints putting pipes in holes drilled for building foundations and in oil exploration.

14.                     Torque wrench:-

Torque Wrench

                    This wrench is having a dial or scale mounted on its handle which indicates the amount of force being applied while operating a not or bolt. These are used where the parts being assembled require a definite force.

                  Some wrench of this type have an indicator which gives a signal when the present force is reached. Others have ratchets or handles which slip off when the desired force is achieved.

SELECTION  OF PROPER SIZE OF WRENCH

        The flat to flat distance of the nut is considered as the size of the wrench.

For metric size of nuts:-

Wrench size= Major dia of the thread X 1.5+ 1mm. Thus a nut of m12 thread requires a wrench 19mm.

FOR BRITISH THREADS:-

Wrench size= Major diameter of the thread in inches X 1.5+ 1/8 inch

Thus ½ inch british  thread requires a wremch of 7/8”    

PRECAUTIONS TO BE TAKEN WHILE USING WRENCHES

1.Discard wrench that are used.

2. Select an open enc or socket wench where ever possible avoid using adjustable wrench. 

3. If there are any burs on the wrench grind or oil stone immediately.

4.Do not add extra leverage to the wrench by attaching pipe or any such device to apply greater force

5. To get extra force never strike the wrench steel hammer.

6. When the nut or bolt is not coming out due to the rusting give sudden but controlled jerks.

7. It is safer to pull the wrench rather than pushing it.