A factory designed and built with the aim to increase the value to the goods. Initial raw materials to a low value if processed in the factory will produce a product, either final products or intermediate products, the higher the point value. By changing the value of the materials to a sold value also changes. Higher selling price, of course, is expected by all because of there factory processing company profit (profit).
Control System
To get a lot of the profits produced goods would have had to have a good quality. Conditions during the production process greatly affects the quality of the product. A process will run well if operated at optimum conditions. Therefore needed a device controller (controller).
The task controller is to reduce the error signal is the difference between the signal settings with the actual signal. This is in accordance with the purpose of control system is to obtain the actual signal (the desired) together with the signal settings. The faster the reaction system following the actual signal and the smaller the error the better the performance of control systems are applied.
If the difference between setting the value of the output value is relatively large, a good controller should be able to observe this distinction to be producing output signals to influence the process. Thus the system quickly change the output process to obtain the difference between setting a regulated output as small as possible.
There are several types of controllers. First Proportional controller (P) which has output comparable to the amount of error signal (difference between the desired quantity with the actual price). Proportional controller output is the multiplication of constants proportional to the input. Changes in input signal causes the system will immediately direct the output of the constant change pengalinya. If a small proportional constant value, proportional controller is only able to correct small mistakes that will result in a slow system response. If the value is increased proportionally constant, the response shows the system more quickly reach a state tunaknya. However, if the value is enlarged so that achieving excessive prices, will cause the system works unstable or oscillating system response will be. Proportional type of controller is usually used to control the liquid level in the tank.
The second is the integral controller which functions to produce a system response has a steady state error. If a factory does not have an element of the integrator (1 / s), proportional controller will not be able to guarantee the output of the system with zero error tunaknya conditions. Integral controller is characterized as an integral. Controller output is strongly influenced by changes in the signal value proportional to the mistake. The output of this controller is a continuous sums of the changes, the output will maintain the previous state as the input changes. In its use is usually proportional integral controller controller combined with a proportional integral controller (PI). The result of the wave-shaped curve. This type of controller is usually used to control the pressure.
The third is a differential controller that has properties such as a derivatives operation. Sudden change in the input controller will cause a very big change and fast. When the input has not changed, the controller output is unchanged. Differential controller is generally used to speed up the initial response of a system, but does not minimize the error in steady state. Working differential controller is only effective in the narrow scope of the transitional period. Therefore, differential controller is never used without any other controller in a system.
Any weaknesses and strengths of each controller proportional, integral and differential can cover each other by combining all three in parallel becomes proportional integral differential controller (PID controller). Elements of the controller proportional, integral and differential individual as a whole aims to accelerate the reaction of a system, eliminate the offset and generate a large initial change. This type of controller is usually used to control the temperature and flow rate in a reactor.
System Human Resources Management
To run a process at the plant not only needs advanced technology and instrumentation control. But also human resources as a designer, implementer and controlling the process. Functionally a company headed by a chief executive in charge of running the company's leadership, setting up systems and working procedures of the company and determine the company's policy. The president holds supreme power in the company.
The president is assisted by several directors, chief, section chief and coordinator of the shift. The number of employees from the level of service to the higher levels will form a pyramid. It means more to the smaller number.
For factories that use the Continue (24 hours a day and 330 days a year), employees are divided into 2 types. First regular employees who have fixed working hours. They work every weekday and holiday on Saturdays, Sundays and holidays. The second shift employees who are divided into 4 teams and there are 3 day shifts while the 1st team squad holiday shifts. Shift division arranged so that after the night shift, employees receive 2 days off. Usually the shift group is 1 sexy processes, utilities, logistics, electrical and instrumentation, workshop, safety and work safety. This usually applies to large factories, such as ceramic manufacturing plant, or chemical factories other.
As for factories that use Batch system, such as factories processed foods (tempeh, tofu), does not apply shift employees, meaning employees work regularly every day.
Economic Feasibility Test
A factory established if feasible meets several requirements including guaranteed his safety and of course can bring profit. In this case we will focus on the economic feasibility only. To set up a factory required substantial capital. This capital may come from investors or from bank loans. Capital used there are 2 kinds of fixed capital and working capital. Includes the purchase of fixed capital equipment, installation, piping, instrumentation, insulation (if necessary), electricity, utilities, buildings, land, engineering and construction, contractor's fee and contingency. Amount of working capital depends on the type of plant and capacity. This working capital includes raw materials inventory, in process inventory, product inventory, extended credit and available cash.
Both the above capital used for production costs which is divided into 3 kinds of direct costs, indirect production costs and fixed costs. Direct production costs are the costs for direct financing of a process, such as raw materials, workers and supervisors, maintenance, plant supplies, patents and royalties, and utility. Indirect production costs are costs incurred to fund things that are not directly assist the production process, such as payroll overhead (such as recreation staff), laboratory, plant overhead, packing and shipping. Fixed costs are fixed costs incurred at the time of factory production or not. These costs include depreciation, taxes and insurance. There was also general expenses include administrative, sales expenses, research and finance. Gains or profits derived from the selling price reduction in production costs.
In addition to the acquisition of profit-oriented, companies also should be able to return capital especially if the capital came from loans. Time for payback percentages expressed by Return On Investment (ROI) is defined as the ratio of earnings to fixed capital. Can also be expressed dalan Pay Out Time (POT). The amount of Return On Investment, and Pay Out Time is different for each type of plant depends on the risk posed by the process in the factory.
Test of economic feasibility is also expressed in graphical form the relationship of production capacity and cost. 2 pieces will form the point of Shut Down Point and Break Even Point. Shut Down Point is a point where the condition that if the process does not run the company will earn a profit but also caused no damage. If the plant operates at a capacity below the Shut Down Point the plant will get lost. Point Break Even Point is a condition that occurs when the plant operates at full capacity. Value Break Even Point is good for a chemical plant generally ranges between 40% - 60%.
By considering all elements, from site selection, technology selection, capacity, and processing technologies and processes supported by the process control and systems of human resource management is good, it can be obtained optimum profit.
