Risk Defect on Du Base Frame Product

During the production process DU base frame product has been found quite a defect occurrence. Defects occurring during the production process of course affect the cost, time and quality of the product production of PT. X, so it is required a handling to overcome the risk of defects that occur so that the product is free from the risk of defects that do not and improve product quality. The method that can overcome the problem above is to predict the risk of product defect by designing a risk management process framework. The risk management planning process is a stage identifying the risk of defects that have occurred or the risk of malformed defects occurred and then conducting a risk-defect analysis, then evaluating the risks of such defects and risk treatment and Monitoring and review. There are also tools and methods used in this risk management study are fishbone and FMEA. Fishbone is used as a tool as a method to cause identification while FMEA is used in risk analysis to determine risk priority number (RPN). From RPN defects that have the highest value will be taken risk evaluation and risk treatment to prevent the same defect. With this research in hopes of the results of quality, cost and production time in DU Base Frame products can remain consistent and give rise to the awareness of the personnel involved in the product manufacturing process. From risk mitigation results found there are 4 out of 56 risk cases that belong to the high-risk category in the process of milling (RPN 288), blasting (RPN 288 & 224) and painting (256). These risks are then conducted advice on the improvements that are discussed with the team and the costumer and the result of defects that occur reduced even eliminated. The importance of the detailed procedures and the awareness of each personnel involved becomes one of the keys to avoid risk in the production process of a product. Keywords―Risk Management, Defect, Product, Fishbone, FMEA.


I. INTRODUCTION 1
Manufacturing is an activity done to process some raw materials or an item into a product that has a greater added value. In manufacturing processes, there is operational waste that is popularized by Toyota Production System. Operational waste that will be used as the topic of researchers focuses on defect. Defect is a factor in the manufacturing process that can affect the outcome of the product. Defects can occur at every step of the manufacturing process, both from input to process to output. The concept of this research was chosen because during the manufacturing process are widely faced with the findings of defect that affect the outcome of products related to the "quality" where this factor is one of the benchmarks for customer satisfaction. For series products (products that are in production continuously and usually have a sequential number) consistent quality aspects become the main focus for the customer or the owner of the product. Therefore, the problem is necessary to do risk management to minimize defects in product outcomes and to increase awareness both at the management level as well as in executing production of products manufacturing activities.

II. METHOD
In 2007, analyzing the causes of electrical energy losses due to interference (electrical distribution network failure mode there are twelve electrical pole damage, power cord, lightning rod, connectors, jumpers, relays, insulators, Transformers, PMT and PMS switches, Buster, MCB, and limiter and gauges) with the FTA and FMEA methods and their mitigation recommendations. Priority improvement that must be done by the PLN based on the consideration of the effects of damage, frequency of damage, and the method of damage control as follows: Damage caused by the transformer [1]. In 2011 Ishikawa diagram or fishbone diagram is used to find the main cause of natural failure in the production of ceramic tiles. The calculation of RPN using FMEA is performed and found that the oven and Press machine have the highest RPN. Then again done analysis of Fishbone diagram for both machines to look for the root of the problem [2]. In 2017 analyzes the constraints that occur in toll road construction. The root cause of the problem is searched using Fishbone diagrams. Then FMEA is used to determine the critical risks that should be immediately solve [3]. In 2018 analyze the cause of the fishbone work accident to find the cause of failure. Then FMEA is used to mitigate errors and create risk maps to find out which failure mode is most urgent to complete [4].

A. Risk
Risks associated with uncertainty. This happens due to less or unavailability of information and insufficient data to predict what will happen. Something uncertain (uncertain) can have two possible consequences of being profitable or detrimental. Unfavorable uncertainty is referred to opportunity, while unfavourable uncertainty is referred to risk [5].

B. Risk Management
Risk management is a method by which management is used to address issues caused by risk. Implementation of management functions in overcoming risk, especially the risks faced by organizations, institutions, companies, families, and the public. So the activities of planning, organizing, arranging, organizing, and supervising (including evaluating) which can be seen in Figure 1 are a risk mitigation program [6].

C. Cause effect diagram fishbone
This diagram is also known as a fish bone diagram because it resembles a fish-like shape. It is also known as Ishikawa diagram because the first time was Prof. Ishikawa who originated from Japan. This Diagram is used to analyze and find the factors that are specifically affected in determining the quality characteristics of the results of the work, looking for the real causes of the problem. There are 4 specific main cause factors that should be observed: work method, machine/tool used, raw material, and work measurement. The example of fishbone diagram can be seen in Figure 2. The cause and effect Diagram have several advantages: 1. Analyze the field condition or actual for the purpose of improving product quality & service, reduce costs & efficient use of resources. 2. Reduce the situation or condition that causes the complain of the consumer and inconsistency in the product. 3. Standardizing operations on existing and future processes. To train and monitor personnel in conducting remediation activities in accordance with the results of decision resolution of the problem.

D. FMEA
Failure Mode and Effect Analysis (FMEA) is a method of non-conformance analysis and errors arising from the design process of a draft work. Failure mode and Effects Analysis form a stage that contains key points in the design process that could potentially be misappropriate and error. Both of these things can happen in the production process on the product to be made. FMEA is used to identify possible failure modes, causes of failure, and the consequences of such failures. Good and precise identification will improve overall product reliability and safety.
FMEA can be explained as a group of events projected to  Recognize and evaluate the potential failure of a product or process and its effects.  Identify actions that could eliminate or reduce the chance of potential failures.  Document the process.
In the use of FMEA method, it is necessary to understand the constituent elements of FMEA, including Severity, Occurrence, Detection, and Risk Priority Number (RPN). Severity is an indicator that describes how significant the result is from a failure if it occurs. Severity is determined without considering other indicators such as occurrence and detection that only consider the description of failure and the description due to failure if occurred [7]. According to Stamatis there are 4 types of Failure and Mode Effect Analysis documentation [6]:

1) Methodologies of FMEA
Methodologies of FMEA is used to analyze systems and subsystems on initial concepts and designs. FMEA of is a type of FMEA focused on the potential failure modes between functions of systems that are system-deficient and aimed at maximizing the quality, reliability, cost and maintainability of a system. The Output generated from the FMEA of is as follows: 1. A list of potential failure modes compiled based on the RPN level. 2. The potential list of system functions that can detect potential failure modes. 3. List the potential of design actions to eliminate failure modes, safety issues, and reduce the occurrence level.
The benefits of the FMEA of are as follows: 1. Help choose an optimal system design alternative. 2. Help determine the prediction (forecasting). 3. Assist in defining the basis for an existing system level diagnosis procedure. 4. Increase the likelihood that potential problems will be considered for actionable. 5. Identifying potential system failures and interactions with other systems and subsystems.

2) Design FMEA
FMEA Design is used to analyze products before they are released in manufacturing. FMEA design is a type of FMEA focused on Failure mode caused by design flaws and aims to maximize the quality, reliability, cost and maintainability of a design. Output generated from FMEA design is as follows: 1. A list of potential failure modes compiled based on the RPN level. 2. List of potential of critical and significant characteristics. 3. A list of potential of design actions that can be done to eliminate the mode of failure, security and reduce the level of occurrence. 4. List of potential of the parameters for the appropriate testing, inspection or detection methods. 5. The potential list of actions that should be done for critical and significant characteristics. The benefits of FMEA design are as follows: 1. Create a priority for an existing design upgrade action. 2. Documenting the reasons used for changes made. 3. Provide information to help verify product design and testing. 4. Help identify critical or significant characteristics. 5. Assist in the evaluation of the needs and design alternatives to be made. 6. Help identify and eliminate potentially emerging security problems. 7. Identifying potential system failures and interactions with other systems and subsystems.

3) The FMEA process
The FMEA process is used to analyze manufacturing and assembly processes. The FMEA process is a type of FMEA focused on Failure mode due to the shortage of existing processes or assemblies. The Output generated from the FMEA process is as follows: 1. The potential list of failure modes based on RPN ratings. 2. A list of potential of critical and/or significant characteristics. 3. The potential list of action recommendations to refer to critical and significant characteristics.
The benefits of the FMEA process are as follows: 1. Identify the process differences and offer corrective action recommendations.
2. Identifying critical and/or significant characteristics and assisting in developing control planning. 3. Make priority of the corrective action. 4. Assist in manufacturing analysis or assembly process.

4) FMEA Service
FMEA service is used to analyze services before reaching consumers. The FMEA Service focuses on the failure modes caused by the system or process. Output generated from the FMEA service is as follows: 1. List of potential errors based on RPN ratings. 2. A list of potential of critical or significant task characteristics or processes. 3. List the potential of a bottleneck process or task. 4. List of potential to eliminate errors. 5. List of potential of system surveillance/process functions. The benefits of FMEA service are as follows: 1. Assists in analyzing the flow of work. 2. Assist in analyzing the system or process. 3. Identify task differences.

E. Severity
Severity is the assessment of the seriousness of the effect of the potential failure mode of the impact/intensity of the event affects the outcome of the process. In this we have to determine all failure modes based on the functional requirements and their effects. An example table of severity is given below.

F. Occurrence
Occurrence is the possibility of how often one causes the failure mode to occur. In this step, it is necessary to see the cause of the failure and how many times it occurs.

G. Detection
In detection dimension, risk can be detected when checked by personnel involved in product production process, the detection category is displayed on Table 3.

H. Risk Priority Number (RPN)
After deciding the severity, occurrence and detection numbers, the RPN can be easily calculated by multiplying these 3 numbers: RPN = Severity × Occurrence × Detection. The small RPN is always better than the high RPN. The assessment results are grouped by category below.

IV. RESULTS AND DISCUSSION
At the risk mitigation phase of this research results from the method FMEA (Failure Mode & Effect analysis), with this mitigation is expected to reduce, minimizing even eliminating the impact of risk and causes of risk result in defect. The risk mitigation process uses criteria to rank the occurrence of severity and detection is selected according to analyzing the records of past failures of any production process. First, the basic requirements of the manufacturing process are studied and then the potential failure mode of the specified process is found. After that defect mode failure is recorded with their severity value. The occurrence rate for potential causes and their prevention is also calculated. The detection value is set to Failure mode and eventually the RPN value is calculated. Result FMEA Chart of DU Base Frame product shown in Table 5.
After obtaining the ranking of the RPN in the FMEA process further provides a proposed improvement to the failure modes that are in the high-risk category show on Table 6. The proposed detail improvement in this case study is only given at risk that includes the high-risk category where defects arising from three risks with high risk have an effect that affects the function and age of the product. For moderate risk & minor risk proposals improvements in general in the form of warnings on each personnel involved to understand the working procedure before starting a production activity.