Steels for Shipbuilding...

Steels for Shipbuilding Ship structures are determined by the ship’s mission and intended service. These determine a ship’s size, complexity and the function of the structural components. There are inherent uncertainties in the loads imposed on the ship structure because of the random nature of the loads imposed by the marine environment. Unlike a fixed, land-based structure, a ship derives its entire support from the buoyancy provided by a fluid, which transmits these loads to the hull structure. Iron hulls replaced wooden hulls in the second half of the 18th century, to be followed up by steel. Since then seagoing ships and inland barges are being regularly designed with several steel grades and shapes. Steels are the most common materials being used for shipbuilding. These steels are rather to meet strict requirements such as strength, flexibility, high manufacturability, weldability, and cost, reparability, etc.  Steels used in the shipbuilding industry also need high cold-resistance, good welding characteristics and increased fracture strength. Modern steel shipbuilding involves the fabrication of a complex steel structure, into which a wide range of ready-made equipment is fixed. Today the principal raw material is steel plate and the layout of  a modern shipyard is arranged to facilitate the flow of steel received from the steel plant through the various processes of making out, cutting, bending, welding, fabricating subassemblies, and final erection of the prefabricated units into the hull and the superstructure. In shipbuilding, there is usually a trade off in the use of material and complex structures. Typically, a complex structure requires more labour and fabrication than a simpler structure, which uses more material. There is also a tradeoff between using more complex structure and the lighter weight of the vessel, as a lighter ship can carry more cargo for a...

Building Customer Loyalty- A Necessity for an Organization...

Building Customer Loyalty- A Necessity for an Organization A customer is an entity (individual, group, society, company, and corporate etc.) who becomes accustomed to buying from the organization. Without a strong track record of contact and repeat purchase, this entity is not the customer, but a buyer. Loyalty is the attachment a customer feels for the employees of the organization, the products and the services. A true customer is grown over time. A loyal customer is one who has the following attributes. Makes regular purchases Purchases across product and service lines Refers the organizational products to others Demonstrates immunity to the pull of the competition Customer loyalty is defined as ‘a customer which over time engage one organization to satisfy entirely, or a significant part, of its needs by using the organization’s products or services’. Customer loyalty means that the customer is loyal to the organization and only turns to a competitor in exceptional cases. The importance of customer loyalty and customer satisfaction has become increasingly apparent to an organization since the industry is facing the situation of oversupply during the recent years. This oversupply condition is bringing to the forth the necessity of building customer loyalty and to have organizational policies which are oriented towards satisfying its customers. Customers can be fickle with their loyalty, and long with their memory. It can be demonstrated by many examples that a single negative incident can ruin a long standing relationship between customer and the organization since there are several viable alternatives are available to the customer in today’s competitive market. Building of the customer loyalty requires the organization to emphasize the value of its products or services and to show that it is interested in building a relationship with the customer. The organization recognizes that...

Understanding Rolling Process in Long Product Rolling Mill Nov27

Understanding Rolling Process in Long Product Rolling Mill...

Understanding Rolling Process in Long Product Rolling Mill  Steel rolling consists of passing the material, usually termed as rolling stock, between two rolls driven at the same peripheral speed in opposite directions (i.e. one clockwise and the second anti-clockwise) and so spaced that the distance between them is somewhat less than the thickness of the section entering them. In these conditions, the rolls grip the material and deliver it reduced in thickness, increased in length and probably somewhat increased in width. This is one of the most widely used processes among all the metal working processes, because of its higher productivity and lower operating cost. Rolling is able to produce a product which is having constant cross section throughout its length. Many shapes and sections are possible to roll by the steel rolling process. Steel sections are generally rolled in several passes, whose number is determined by the ratio of initial input material and final cross section of finished product. The cross section area is reduced in each pass and form and the size of the stock gradually approach to the desired profile. Rolling accounts for about 90 % of all materials produced by metal working process. It was first developed in the late 1500s. Hot Rolling is carried out at elevated temperature above the re-crystallization temperature. During this phase, the coarse-grained, brittle, and porous structure of the continuously cast steel is broken down into a wrought structure having finer grain size and improved properties. A long product rolling mill comprised of equipment for reheating, rolling and cooling. The primary objectives of the rolling stage are to reduce the cross section of the incoming stock and to produce the planned section profile, mechanical properties and microstructure of the product. Major parameters in the three...

Steels for Automotive Applications...

Steels for Automotive Applications Steel has been a leader in automobile applications since 1920s. Currently, steel is the primary material in body and chassis structures. It is the backbone of the entire vehicle. In cars, these days, steel makes up about 65 % weight. It plays many roles in present day vehicles. It protects occupants, provides positive driving experience, reacts to road loads, provides comforts, and provides attachment points to other components of the vehicle. As there is a high emphasis on greenhouse gas reductions and improving fuel efficiency in the transportation sector, the automobile industry is investing significantly in lightweight materials. The industry is moving towards the objective of increasing the use of lightweight materials. It is giving priority to the activities connected with the development of new materials, forming technologies, and manufacturing processes. The weight reduction is still the most cost-effective means to reduce fuel consumption and greenhouse gases. It has been estimated that for every 10 % of weight eliminated from a vehicle’s total weight, fuel economy improves by 7 %. This also means that for every kilogram of weight reduced in a vehicle, there is around 20 kg of carbon dioxide reduction. Over the last decade, a strong competition between steel and low density metals has been observed in the automobile industry due to the increasing requirements of passenger safety, vehicle performance and fuel economy. The materials used in automotive industry need to fulfill several criteria before being approved. Some of the criteria are the results of regulation and legislation with the environmental and safety concerns and some are the requirements of the automobile users. In many occasions, different factors are conflicting and therefore a successful automobile design is only be possible through an optimized and balanced solution. Around 65...

Management of Man and Machine...

Management of Man and Machine Human intervention of the production processes has undergone a big change after automatic and computerized controls have been introduced for the production processes. A large number of activities previously done by human beings have been taken over by the automation. But this has not eliminated the need for operator for the running of the equipment/process though his role has changed a lot with the automation of the process. Today mass production would not exist without the usage of automated and flexible manufacturing processes. These automated processes need machines and equipments which require human intervention for controlling them. Close and harmonious interaction by operators with their machines is a necessity for the productive output. An integrated and coordinated communication between machines and the men operating them is needed for the productive output. The complexity of industrial processes has greatly increased during the last few decades. This tendency has originated due to a number of reasons, such as (i) the enlargement of the scale of the modern plants, (ii) the required specifications dealing with the product quality, (iii) the need for the energy conservation, (iv) the requirements for the environmental pollution control, (v) the necessity of safety in the plant, and (vi) the progress in process control and informatics creating totally new possibilities. This essential change in the process operation has led to the definition of new human operator tasks. In the last thirty years, human manual control has become much less important and human supervisory control has been developed as the main concept for man and machine interactions. The tasks of the human supervisor are now predominantly cognitive ones, and contain at least the following six subtasks namely (i) the monitoring of all data presented to the human supervisor, (ii)...