Hammers

INTRODUCTION:-

                 Hammers are tools which are used to strike blows.

TYPES OF HAMMERS:-

        The commonly used types of hammers are

1.    Ball peen hammers

2.    Cross peen hammer

3.    Straight peen hammer

4.    Claw hammer’

5.    Sledge hammer

6.    Soft hammer

7.    Power hammer

    USES OF HAMMER:-

1.  Ball peen hammer:-

       This is a commonly used hammer in the workshop and homes. The peen of this hammer is ball shaped, therefore it is used for forming a rivet head by spreading the shank of a rivet.

2.  Cross peen hammer:-

        The peen of this hammer is flat and at right angles to the handle. This is widely used in sheet metal work.

3.  Straight peen Hammer:-

      The peen of this hammer is flat and at right angles to the handle. This is widely used in sheet metal work.

4.  Claw Hammer:-

      The peen of this hammer is split in the  center and bent like a claw. This is mostly used by carpenters for driving or removing nails from wood.

5.  Sledge Hammer:-

       This is a big hammer mostly used by black smiths, stone breakers etc. For heavy job usually these hammers are double faced.

6.  Soft Hammer:-

       Steel hammers leave hammers marks on the surface of the workpiece and spoil it when it Is required to strike on a finished surface without spoiling it, soft hammers are used.

      There are two types of soft hammers are used. Those which are made of soft metals like brass, copper, lead and those which are made of non-metals like wood, plastic, nylon etc. Soft hammers are made of soft metals used on steel work pieces for example seating a workpiece on parallel block in a vice.

     A soft hammer is known by the name of the material of which it is made for example lead, hammers, copper hammer, nylon hammer etc. But a soft hammer made of wood is generally known by the name “ mallet”.

7.  Power Hammer:-

      Power hammers are operated by electric motor, steam or compressed air. Hey are used where a great force is required for example heavy forging work. Usually the striking force of a power hammer is in tons. The different types of power hammers are:

1.  Gravity drop hammer

2.  Steam hammer

3.        High steam pneumatic hammer

4.     Counter blow electric hammer

      SIZE OF A HAMMER:-

          Size of a hammer is specified by its weight. Ball, cross and straight peen hammers come in 100,200, 300,400,500,600, 800 and 1000 grams weight, while sledge hammers are mad from 1 ½ to 10KG of weight.

MATERIAL OF HAMMERS:-

      Steel hammers are made out of medium carbon stee containing 0.5 to 0.7% carbon (T55). Drop forged hammers are the best. A good hammer should have hardness HRC 47 on both face and peen.

SAFTEY PRECAUTIONS:-

1. Before using a hammer, see that the handle is tightly fitted in the eye hole with a wedge and the handle is square with the head.

2. Never handle the hammer with oily hands.

3. While striking see the job and  not the hammer head.

4. Do not use  a mush roomed hammer if a mush room forms around the face of the head, remove it by grinding. while grinding see that the head is not over heated.

5.  Or better results hold the hammer ¾ length away from the head.

6. If the wedge becomes loose, replace it with a larger wedge.