what is meant by conveyor? or Conveyor system?

          A Conveyor system is a standard piece of mechanical material handling equipment or assemblie, that moves materials or packages from one location to a different location with minimal effort over a fixed path. 

Image source: Wikipedia

          They typically contains frames that support rollers, wheels or belts and that they could also be motor powered or manual devices. Conveyors are particularly helpful in applications involving the transportation of heavy or bulky materials like gravel or aggregate. They are extremely popular in the material handling and packaging industries due to efficient and fast transportation of materials. 

         They also include moving belts that used in belt conveyors, bucket and vertical conveyors that raise material, vibrating conveyors that use vibrating motion to maneuver material, and overhead conveyors from which things suspend throughout transport. Different sorts include screw conveyors for moving liquid or material consisting of small grains, chute conveyors are located on sleek surfaces and gravity, and drag or tow conveyors that use cables to pull objects on. Walking beam conveyors move objects by forward sweep mechanism to planned positions for manufacturing operations.
          The verity of conveyors is infinite, but the two major classifications used in typical plants are Pneumatic and Mechanical.

Note: The power requirement of a Pneumatic conveyor system are much greater than for a mechanical conveyor of equal capacity. 

Image Source: http://foodanddrinkmatters.co.uk/carefully-customised-conveyor-solutions/

Fundamental Tolerance Chart

By K-code-g - Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=48589598

PUMP POWER CALCULATION

SUMMARY

          In order to move and increase the pressure of a fluid, power is consumed by a pump, fan or compressor. The power requirement of pump depends upon many factors, including pump and motor efficiency, differential pressure, density of fluid, viscosity and fluid flow rate. In this article we are going to discuss the relationships to determine the pump power requirement.

DEFINITIONS

Ph​​	:	Hydraulic power of the pump (kW).
Ps​​	:	Shaft power of the pump (kW).
Pm​​	:	Required power to the Motor (kW).
Q	:	Volumetric flow of fluid through the pump (m3/h).
ρ	:	Density of the fluid being pumped (kg/m3).
g	:	Gravity (9.81 m/s2).
h	:	Head produced by the pump (m).
dP	:	Differential pressure across the pump (kPa)
ηp​​	:	Pump efficiency (%).
ηm​​	:	Motor efficiency (%).

HYDRAULIC POWER

          Hydraulic power, also known as absorbent power, indicates the power imparted on the fluid which is to be pumped to increase the fluid's pressure and velocity. Hydraulic power can be calculated using one of the formulae below:

Units	Formula
P - kW Q - m3/h ρ - kg/m3 g - m/s2 h - m	Ph = Qρgh/3.6 x 10^6​
P - kW Q - m3/hr dP - kPa	Ph = QdP/3,600​​
P - kW Q - L/min dP - kPa	Ph= QdP/60,000​​
P - kW Q - L/s dP - kPa	Ph = QdP/1,000​​

SHAFT POWER

          The power supplied by the motor to the pump shaft is called "Shaft power". It is defined as the sum of the hydraulic power and power loss due to inefficiencies in the transmission of power from the shaft to the fluid. The shaft power of pump is generally calculated as the ratio of hydraulic power of the pump to the pump efficiency. 

                        Ps = P_h/η_p

Ps = Shaft power

P_h = Hydraulic power of pump (discussed above)

η_p = Pump efficiency

MOTOR POWER

          The power consumed by the pump motor in order to turn the pump shaft is called as "motor power". The motor power is the sum of shaft power and power losses while converting electrical energy into kinetic energy. Mathematically motor power is calculated as "shaft power divided by motor efficiency".

P_m = P_s/η_m​

P_m = Motor power

P_s  = Shaft power

η_m = Motor efficiency

Some OTHER FACTORS WHICH INCREASE REQUIRED POWER

          In addition to the motor we can use some other drive features which will increase the power requirement of pump to transfer a perticular fluid. 

These are :

1) Belt drives 

2) Gear drives

3) VSD's (Variable speed drives)

THEODOLITE AND IT'S TYPES

          A Theodolite is a precision instrument for measuring angles in the horizontal and vertical planes. Theodolites are mainly used for surveying applications, and have been adapted for special purpose in areas such as Meteorology and Rocket launch technology. A modern theodolite consists of a movable telescope mounted within two perpendicular axes - the horizontal (or) trunnion axis, and the vertical axis. When the telescope is pointed at a target object, the angle of each of these axes can be measured with great precision, typically to seconds arm. 

Size of a theodolite is specified by

a) the length of telescope

b) the diameter of vertical circle

c) the diameter of lower plate

d) the diameter of upper plate

Ans: C

International tolerence (IT) grade

          IT Grade refers to the International Tolerance Grade of an industrial processes defined in ISO 286. This mechanical tolerence grade identifies what tolerences a given process can produce for a given dimension.

The specific tolerence for a particular IT grade is calculated by the following formula

Where :

               . T is the tolerence in micrometers {µm}

               . D is the geometric mean dimension in millimeters [mm]

               . ITG is the IT grade, a positive integer.

The larger the ITG, the looser the tolerence that can be achieved.

Application: 

          Almost all manufacturing processes have an IT grade associated with, indicating how precise it is. IT grade offer guidence for typical manufacturing method capability or how precise one can expect manufacture of a specific option or feature.

          When designing a part, an engineer will typically determine a key dimention (D) and Tolerence on that dimension. Using this formula, the engineer can determine what IT Grade is necessary to produce the part with those specifications. For example, if injection molding has an IT Grade of 13 and a part needs an IT Grade of 5, one cannot injection mold that part to those specifications. It is useful in determining the processes capable of producing parts to the needed specification.