Machine Parts

                          Boiler Boiler: A steam boiler is usually a closed vessel made of steel. Its function is to transfer the heat produced by the combustion of fuel to water and ultimately to generate steam. Types of boiler:            1. Fire tube or smoke tube boiler            2. Water tube boiler                                                                                                             Figure: Boiler Fire tube boiler: In fire tube steam boilers, the flames and hot gases, produced by the combustion of fuel pass through the tubes which are surrounded by water. Fire tube boilers are generally used for relatively small steam capacities and low to medium steam pressure. As a guideline fire tube boilers are completive for steam rates up to 12000kg/h and pressures up to 18 kg/cm².Fire tube boilers are available for operation with oil, gas or solid fuel.                                                                

IED means the Industrial Engineering Division. The main function of IED is that the customer handling. At first when a party/customer (personnel/government/non-government institute/factory) needs to make a job, it comes to BITAC and meets with IED section. Sometimes all operations of the job can not be performed in BITAC. In that case, a quotation form is given to the party and that operation is performed from any outer shop. Then IED estimates approximate cost of the job or product according to the drawing or sample and number of products.                                                     The total cost consists of material cost, casting cost (if necessary), matching cost (depreciation cost, electricity bill, salary of the workers), overhead cost (25% of total cost and it ultimately goes to Bangladesh Bank), emergency cost (if necessary, generally 10% of the total cost), packing cost (if necessary) and transport cost (if necessary).                               

Plastic: Polymer or plastic are the long molecular chain of monomer ( basically hydrocarbon HC ) which is formed by polymerization. Types of plastic :   Plastic are mainly two types- (1)   Thermo plastic (2)     Thermo set plastic                                                                                                                                                                                             Figure: Rubber & Plastic Technology 1)Thermo plastic : This type of plastics are   reprocess able. Polythene, Polyvinyl chloride ( PVC ), Poly amide ( PA ), Polystyrene( PS ), Poly propylene ( PP ) etc. are the example of thermo plastic. 2)Thermo set plastic : This type of plastics are not reprocess able. Phenol formaldehyde ( PF ),Under formaldehyde ( UF ), Epoxy resin ( EP ) etc. are the example of thermo set plastic.                                    Process of plastic : 1.       Injection molding 2.       Extrusi