What are the two scales calibrated in screw gauge?

A screw gauge has two scales, one rotating scale which can be found on its rotating cylindrical part it is also called a circular scale and the other one can be found on its stationary sleeve which is called the main scale or sleeve scale. Generally, the least count on the main scale is 0.5 mm.

What are the two types of error in screw gauge?

These are very common in micrometer screw type measuring devices such as the screw gauge. One such error is the zero error which happens when the zero of the main scale and the circular scale do not match when the jaws are closed. 3.) Another common error due to a defect in the apparatus is the backlash error.

What are the two parts of vernier scale?

Parts of a vernier caliper:

  • Outside jaws: used to measure external diameter or width of an object (Blue)
  • Inside jaws: used to measure internal diameter of an object.
  • Depth probe: used to measure depths of an object or a hole ( not shown in this model)
  • Main scale: gives measurements in mm.
IT IS INTERESTING:  How is a Grade 5 bolt identified?

What is main scale reading in screw gauge?

The main scale reading is the first reading on the main scale immediately to the left of the zero of the vernier scale (3 mm), while the vernier scale reading is the mark on the vernier scale which exactly coincides with a mark on the main scale (0.7 mm). The reading is therefore 3.7 mm.

What is pitch scale and head scale in screw gauge?

There are two parameters used in every screw gauge. They are pitch and least count of a screw gauge. Pitch: Pitch of the screw gauge is defined as the distance moved by the spindle per revolution which is measured by moving the head scale over the pitch scale in order to complete one full rotation.

How many scales are in a screw gauge?

Just like Vernier calipers, a screw gauge also holds two scales – a key scale and an additional scale.

What are the parts of screw gauge?

A screw gauge consists of a “U” shaped metallic structure, which is attached to a hollow cylindrical tube on one end. The hollow tube has a uniformly threaded nut inside it.

Thus the main parts of a micrometer screw gauge are:

  • Frame.
  • Anvil.
  • Spindle.
  • Sleeve.
  • Thimble.
  • Ratchet.
  • Screw.
  • Lock.

What is the function of screw gauge?

Figure 6: Screw Gauge using micrometer

The micrometer shown in Figure 4 has a pitch of 0.5 mm. It means that for one complete rotation of the thimble scale, 0.5 mm distance is traveled by the spindle. There are 50 divisions on circular scale. The least count will be 0.01 mm calculated as below.

IT IS INTERESTING:  What is another way of saying screwed?

What are main parts of vernier callipers?

Vernier scale or Nonius, outside jaws, inside jaws, knob, depth probe, and locking screw are some of the main components of the vernier caliper.

How do you measure screw gauge?


  1. Find the value of one linear scale division (L.S.D).
  2. Determine and record the pitch and least count of the screw gauge.
  3. To find the zero error, bring the plane face B and A near. …
  4. Move face B away from face A. …
  5. Linear scale reading (L.S.R) is recorded by noting down the no. …
  6. Let n be the no.

What are the two types of reading in physics?

There are two types of scale reading uncertainties; analogue and digital. A ruler is an example of an analogue scale. In this situation there may be a degree of approximation to determine an exact length.

What is head scale and pitch scale?

A scale graduated in millimetres parallel to the axis of thimble is called pitch scale. It is also known as main scale of screw gauge. A scale graduated on the thimble is called head scale. This head scale is divided into 50 to 100 equal parts.

What is pitch and scale?

In music theory, a scale is any set of musical notes ordered by fundamental frequency or pitch. A scale ordered by increasing pitch is an ascending scale, and a scale ordered by decreasing pitch is a descending scale.