Submersible Pump

  • —A submersible pump (or electric submersible pump (ESP) is a device which has a hermetically sealed motor close-coupled to the pump body. The whole assembly is submerged in the fluid to be pumped.
  • —A submersible pump is a pump that is able to be placed underwater and still carry out its intended purpose. Some pumps may be designed to work while being fully submerged, whereas others may be submerged or placed in a dry area.
  • —A submersible water pump pushes water to the surface, instead of sucking the water out of the ground like above ground water pumps.

Submersible Pump

Working Principle

  • The submersible pumps used in ESP installations are multistage centrifugal pumps operating in a vertical position. Although their constructional and operational features underwent a continuous evolution over the years, their basic operational principle remained the same.
  • —Produced liquids, after being subjected to great centrifugal forces caused by the high rotational speed of the impeller, lose their kinetic energy in the diffuser where a conversion of kinetic to pressure energy takes place.
  • The pump shaft is connected to the protector by a mechanical coupling at the bottom of the pump. Well fluids enter the pump through an intake screen and are lifted by the pump stages.
  • Other parts include the radial bearings (bushings) distributed along the length of the shaft providing radial support to the pump shaft turning at high rotational speeds.
  • An optional thrust bearing takes up part of the axial forces arising in the pump but most of those forces are absorbed by the protector’s thrust bearing.

Applications

  • The pump shaft is connected to the protector by a mechanical coupling at the bottom of the pump. Well fluids enter the pump through an intake screen and are lifted by the pump stages.
  • Other parts include the radial bearings (bushings) distributed along the length of the shaft providing radial support to the pump shaft turning at high rotational speeds.
  • An optional thrust bearing takes up part of the axial forces arising in the pump but most of those forces are absorbed by the protector’s thrust bearing.

—Efficiency: Compared to the ordinary pumps, the submersible pumps are more efficient as it pumps liquid which is close to the pump. It therefore functions less than the ordinary pumps. As these pumps are placed inside the sumps, it can detect the level of water quite easily.

—Noise level: The submersible pumps seldom produce less amount of noise as it is submerged under water. The walls of the sump help to soften the sounds caused by the pumps. The ordinary pumps are placed outside the wells or sumps which creates a huge amount of noise.

—Safe: These pumps are quite safe compared to the other types of pumps as all the potential dangerous components of the pumps are placed under water. It is usually covered and seldom involves the prospects of children tampering with its internal components and valves.

Disadvantages:

  • —The largest disadvantage of these pumps is that you put it in the water. This means it will have a shorter life because it is sitting in and sucking up muck from your pond. It is also harder to clean and maintenance because it is sitting on the bottom of the pond.
  • —There is the chance the pump will become corroded and lose its seals, thus allowing liquid to penetrate into the motor housing and causing substantial damage to the unit.

Conclusion:

—The submersible pump was driven by its own power source – mains electricity or generator – so the educator trucks could switch off their engines while being filled. This reduced fuel costs to the educator companies. Moreover, it reduced the amount of noise generated by the works, such that there was a noticeable reduction in impact on adjoining residents. This was the same pattern for both the mains electricity version, and the generator-driven version, which was extensively sound-proofed.

—In my opinion, a submersible pump may have a place in heavily populated residential areas as a source of water supply. In this application the submersible advantage of quite operation, unobtrusive surface equipment and low initial cost may outweigh the disadvantage.

Fast and Loose Pulley

When a number of machines are operated from a single power source, each machine is provided with a fast and loose pulley arrangement. With this arrangement, any machine may be started or stopped at will, while the lay shaft is running continuously. Image below shows the arrangement of a fast and loose pulley. In this, the fast pulley is mounted on the shaft with a keyed joint, whereas the loose pulley runs freely on the shaft. The diameter of the loose pulley is slightly less than that of the fast pulley so that when the belt is shifted on to the loose pulley, its tension is reduced. Power is transmitted only when the belt is on the fast pulley. Loose pulley takes care of the idling time of the machine and does not transmit any power.

Fast and Loose pulley

Stuffing Box Details

It is used to prevent loss of fluid such as steam, between sliding or turning parts of machine elements. In a steam engine, when the piston rod reciprocates through the cylinder cover; stuffing box provided in the cylinder cover, prevents leakage of steam from the cylinder. Image below shows the various parts of a stuffing box. At the base of stuffing box body 1, a bush 3 is placed such that the bevelled edge of the bush is at the inner side of the body. Gland 2 is placed at the other end of the body and is connected to the main body by means of studs 4 and nuts 5. The space between the reciprocating rod and the bush and the gland is packed with a packing material such as mineral fibres, leather, rubber or cork. 

Stuffing Box

Stuffing Box 3D

https://d2t1xqejof9utc.cloudfront.net/screenshots/pics/3515d196e524345f50c354a35b8dc951/medium.bmp

Pedestal Bearings or Plummer Block

This type of bearing consists of I) a cast iron pedestal, ii) gun metal, or brass bush split into two halves called “brasses”, and iii) a cast iron cap and two mild steel bolts. The detailed drawing of a pedestal bearing is shown in image below. The rotation of the bush inside the bearing housing is arrested by a snug at the bottom of the lower brass. The cap is tightened on the pedestal block by means of bolts and nuts. The detailed part drawings of another plummer block with slightly different dimensions are also shown in image below.

Assembled Plummer Block

Assembled Plumber Block

Details of Plummer Block

Details Plumber BlockPlummer Block 3D

https://blogpuneet.files.wordpress.com/2013/10/c64dd-plummerblock01.jpg

Screw Jack

Screw jacks are used for raising heavy loads through very small heights. Picture below shows the details of one type of screw jack. In this, the screw 3 works in the nut 2 which is press fitted into the main body 1. The tommy bar 7 is inserted into a hole through the enlarged head of the screw and when this is turned, the screw will move up or down, thereby raising or lowering the load.

Screw Jack Details
Screw Jack AssembledScrew Jack 3D


Tool Post

Single Tool Post

Tool posts of several designs are available to support and hold the cutting tools in lathe machines. Image below shows the part drawings of a single tool post, which supports one cutting tool at a time and is used on small sized lathes. This unit is fixed on the compound rest of the lathe carriage. The single tool post consists of a circular body 1 with a collar at one end and a threaded hole at the other. A vertical slot is provided in the body to accommodate the tool/tool holder. The body is slid through the square block 5, which is finally located in the T-slot, provided in the compound rest. The design permits rotation of the body about the vertical axis. A circular ring 4 having spherical top surface is slid over the body and the wedge 3 is located in the vertical slot. The tool / tool holder is placed over the wedge. By sliding the wedge on the ring, the tool tip level can be adjusted. The tool is clamped in position by means of the square headed clamping screw 2, passing through the head of the body. Figure 19.8 shows the assembly drawing of a single tool post.

Single Tool Post

Single Tool Post Assembled

Square Tool Post

This is used to hold four different tools at a time. The tool holder may be rotated and clamped to facilitate the use of any one of the tools at a time. The details of the square tool post are shown in image. The tool holder 1 is located on the base plate 2 by means of the stud 3. It can be fixed to the base plate in any position rigidly by the clamping nut 4 and handle 5. The knob 6 is fitted to the handle for smooth operation. The tools are held in the tool post by means of the set screws 7. Each tool can be indexed readily by rotating the tool holder on the base plate and located in the correct position by the spring 9 and the ball 10. The ball is seated in the V-groove, provided for this purpose in the base plate.

Details of Square Tool Post

Square Tool Post 3D

Oldham’s Coupling

It is used to connect two parallel shafts whose axes are at a small distance apart. Two flanges, each having a rectangular slot, are keyed, one on each shaft. The two flanges are positioned such that, the slot in one is at right angle to the slot in the other. To make the coupling, a circular disc with two rectangular projections on either side and at right angle to each other, is placed between the two flanges. During motion, the central disc, while turning, slides in the slots of the flanges. Power transmission takes place between the shafts, because of the positive connection between the flanges and the central disc.

Oldham's Coupling