DMAIC is a method which pursues a structured model of carrying out situational analysis of an organization’s work processes and activities that enable the organization to achieve its key business objectives. The process elementally consists of five core stages meant to fulfill the analytical objective. PowerPlus battery manufacturing company is company that has dedicated its processes in the manufacture of various types of batteries. The two major types of batteries that the company produces are automobile batteries and industrial batteries (Kumar & Kumar 2006, p.360). The company has an efficient customer satisfactory plan where the management provides a warranty of 18 months for its diesel locomotive starter batteries that are manufactured by the company. After a long period of smooth operation devoid of major operational problems the company started receiving complaints from its esteemed customers regarding the efficacy of the battery life warranty. The complaint was essentially that the battery life started depreciating leading to the need for a critical outlook and assessment to be carried out efficiently focusing upon the company’s critical manufacturing process. Majority of the customer complains suggested that other battery alternatives were giving better battery life in comparison to PowerPlus battery manufacturing company prototypes.
The major aim of the define stage is to identify some of the main matters of concern considering critical to quality parameters (Krishna 2008, p.229). The end users of the diesel locomotive starter batteries are heavy commercial vehicles, midsized SUVs, and small vehicle car (family size) car owners. These form the main targets of the final product, which is elementally in the form of an operational battery meant to support all the core functions of the vehicle classification. Furthermore, the batteries can also be used in other settings, for instance, some farm machinery having similar load handling and capacity like the heavy commercial vehicles. The batteries need to fulfill all the required properties, which are: charge taking capacity, capacity of battery, container integrity, correct polarity settings, and connectors or electrodes working in their respective ambient conditions.
In performing a successful measuring stage a working metric measure is essentially applied in ascertaining the process capability (Krishna 2008, p.229).
The critical quality parameters are essentially as follows:
The batteries have to be subjected to testing analyzers in order to determine their ability of taking charge once they have been bought by the client. The testing process essentially involves the incorporation of different elements.
The capacity of the batteries must be ascertained through testing in order to ensure that the charge taking ability is essentially limited to the desired parameters. Once batteries have been produced and the electrolytes filled, there is need to test each battery cell by using automated analyzers to set respective charge capacities capable of starting the desired class of the vehicle.
The complete batteries which have been produced are essentially subjected to quality analysis criterion, which entails the use of specific laser beams set at required wavelengths to detect any form of openings or leaks. In case there is a warning or an integrity problem occurring, the detector has a sound buzzer which goes on signaling the process engineer of an impending problem (Gachanja & Bolingo 2008, p.44). It is then the roles of the engineer to proof check all the process elements to ensure that the manufacturing activity proceeds uninterrupted. These are then removed from the rest of the selection, which has been ascertained as being operational.
The normal polarities of a battery entail the presence of a functional positive and negative electrode. The normal configuration are essentially ascertained through the application of a testing system capable of discharging charge at desired rates, for instance, a connector desired to discharge capacity of 24 volts could give a reading of zero, consequently insinuating the fact that there is an impending reverse polarity problem.
All connectors need to be in the functional form, which is ordinarily in solid form. However, there are cases in which the connectors have been melted because of the nature of the electrolyte, which is ordinarily composed of sulphuric acid element. Any signs of melted electrodes imply that there is an occurrence of degradation or corrosion of the connector terminals (Gachanja & Bolingo 2008, p.45). This could imply that majority of the connectors are essentially made from materials that are incapable of handling the acidic strength of the sulphuric acid electrolytes.
Process Flowchart Showing Different steps involved During Manufacture & how they are performed
The process chart entails a depiction of the critical steps involved during manufacture of the battery model. In addition, it also entails a description of some of the major technology put to application, respective outputs involved, a thorough consideration of the human skills involved in accomplishing and directing different tasks, different points of output at each different step, elements/participants in the process, time taken to achieve the different design goals, and existence of a benchmark process to proof check and ascertain the desired outputs.
Manufacture of Positive and Negative Plates
This is essentially the role of the Plates engineer who is in charge of this manufacturing section. The time taken to fulfill the whole operation is 3 hours. The engineer works with three other workmen with a goal of ensuring all plates have been properly molded according to the molding electrode shape and material.
Insulation of Positive and Negative Plates
This step essentially involves the insulation of the electrodes that have been produced in the previous processing section. Insulation is essentially done to ensure no transmission of electrolyte charge unnecessarily. The process takes approximately 1 hour to complete and the personnel in charge is the designated plates engineer. Here the insulation material is used to fulfill coat the electrodes as its desired (Gachanja & Bolingo 2008, p.27).
Manufacture of the Electrolyte Component
This involves the manufacture of the electrolyte component of the batteries. The type of acid used is Sulphuric acid and its major aim is to generate the required ion components that will conduct charge sufficiently. Since sulphuric acid is essentially a reactive fluid care must be taken to protect the operators from being accidentally burnt, therefore there is maximum use of protective clothing and devices (Gachanja & Bolingo 2008, p.34). The process takes relatively 6 hours going by the assigned indicators, and the personnel in charge is the electro-cell engineer.
Here the container element used as casing material for the electrolyte is manufactured in a well controlled process. The material used for the casing material is a composition of plastic and other chemical elements to give the desired strength and endurance (Gachanja & Bolingo 2008, p.37). Furthermore, the container needs to be a non-reactive material and non corrosive since this would potentially affect functionality of the battery components in the chance the two qualities are not fulfilled.
Flooding of the Container with the Electrolyte
The final process before the batteries proceed to the packaging and supplies section is the flooding of the battery container by the produced electrolyte. The electrolyte is then filled up to its required level. There are analyzers, which have been installed to proof check the electrolyte level so that the minimum produced charge becomes 24 volts going by charge capacity (Gachanja & Bolingo 2008, p.33).
The following displays a Pareto chart for the portraying the different Critical to Quality components which are considered in the analysis of the perceived failure rate of the batteries designed for the processes.
The main aim of this step is to generally implement the proposed solutions which were identified during preparation of the define stage and focused upon through targets in the measuring stage (Krishna 2008, p.229). This can essentially be accomplished through the application of a fishbone diagram as illustrated the following section. “The fishbone diagram is primarily used in the defining, analyze, and improve steps of the DMAIC process” (Brusse 2005, p.53). Here the identification of the key process input variables or KIPVs is essentially carried out to establish the main control points and other input variables. The following therefore represents the key elements of the entire design process as explained in the fishbone diagram. The aim is to establish some of the key cause and effect relationships among critical design elements, which are taken into due consideration during the design process.
The following are some of the critical problem causes:
During manufacture of electrodes the temperatures need to be ambient or else there will be major flaws. The need to control temperature levels is one of the critical elements of ensuring that the respective quality parameters regarding electrodes manufacture are being met.
The battery capacity essentially needs to be within the range of 450 amperes per hour. This is the final voltage capacity recommended for all batteries sold in their respective ‘out of shop states.’ It was established that there were certain batteries, which were either not well checked before being supplied or the electrolyte material used must have been of degraded quality.
“A tubular casing in gauntlet is used for positive plates – the anode, while a grid structure is used for the positive plates – the cathode” (Kumar & Kumar 2006, p.360). In some cases there appeared to be a problem with the casing material leading to leaks occurrence. The electrode materials are essentially made from a combination of positive and negative ends which have been insulated using key separators (Gachanja & Bolingo 2008, p.29). In some battery elements the separator material, which should essentially be made from a porous material to give way for free ions locomotion, appeared to block this movement.
Majority of the staff were skilled personnel, however there was lack of supervision. Supervision as an element of the whole process is critical as it serves to incorporate all the necessary process elements into the manufacturing process in order to integrate everything. In addition to supervision there was a need to train the staff on basic quality improvement and enhancement in order to deter instances of low quality.
The techniques were generally adhered to in most of the cases. The techniques used for processing the diesel locomotive starter batteries are step-guided techniques. Operational manuals are essentially provided and placed at strategic points of the manufacturing plant in order to guide the respective processes and enable manufacturing abilities (Gachanja & Bolingo 2008, p.28). In addition, the major aim of the manuals is to provide all the necessary elements, which the respective section engineers can make a reference point.
Majority of the machine components were in good condition, the only exemption was the analyzer being used to control flaws detection mechanisms. This could be attributed to the constantly varying electrolyte balance states according to the periodic data of the manufacturer. The analyzer was potentially noted to result in the provision of either inflated results in some cases and other cases it could be attributed to the resultant low values. This therefore needs to be corrected in order to prevent further wrong values.
The following are some of the critical problem causes:
Temperature analyzers need to be installed and their readings checked on a periodic basis. This should essentially be implemented using a progressive environmental monitoring program, which will be a duty of the respective process engineers. The environmental monitoring program will entail the application of standard temperature sensors, which will be used to record changing temperatures over time in order to ensure that this does not lead to the dangerous accidents considering the nature of electrolytes and their ability to potentially explode without any prior warning (Gachanja & Bolingo 2008, p.53).
The battery capacities should be monitored in regard to polarity configuration of the electrodes. The tester material in use should be tested to ensure the readings being given are accurate at all times. This data will be recorded on a periodic basis while taking into account the critical processes, which are fundamentally ongoing. This data will be plotted in a periodic graph and this will consider the fact that charge capacities cannot be fundamentally precise but they need to be more than the required charge capacity by a few points, say 24.1 V, 24.2 V, 24.3 V, and 24.4 V (Gachanja & Bolingo 2008, p.54). This will ensure that the charge capacities do not go over the required level.
The laser beam element used to inspect flawlessness of the battery casings needs to be properly installed with working detectors. An efficient monitoring program needs to be incorporated in order to cater for the lacking characteristics. This will also entail checking all the necessary supply elements and provisions being carried out by the authorized raw material input suppliers (Gachanja & Bolingo 2008, p.23). A mechanism will therefore be established to ascertain all the necessary input elements to prevent compromising the progression of the precise processing elements.
Staffs need to be supervised adequately in order to avoid future problems. This will be done by the respective sections in-charge personnel. In order to ensure maximum efficacy of the program there is need to incorporate a strategy whereby staff members are required to follow an established reporting protocol which will be operational on a daily basis. This will enable follow-up incase human related flaws occur in the near future (Gachanja & Bolingo 2008, p.55)
No measures were recommended since techniques were well adhered. This could be attributed to the automated element of the machines. In as much techniques were well adhered to, there is still need to incorporate training modules, which will cater for the supervisory gap and the introduction of better work shift patterns.
A better analyzer needs to be installed to monitor all critical processes. There is need to institute a maintenance schedule for all machine components. This will entail implementing an efficient monitoring and evaluation program that will essentially run across the relevant departmental settings. This also calls for proper running of the organization while taking due consideration of the critical quality implements. In addition, each manufacturing component needs to be subjected to standard setting organizations, such as those mandated by existing governmental instruments (Gachanja & Bolingo 2008, p.23). The essence is to ensure that the battery components match those of standard recommended standards in order to benefit the general clientele and manufacturing institutions.