Workshop production line design process:
Single-species assembly line organization and design of the general content are:
① Determine the production of the assembly line beat;
② Organization of the process of simultaneous and the workplace (equipment) needs;
③ Determine the need for workers in the assembly line, a reasonable number of people;
④ Select a reasonable means of transport;
⑤ Development of the assembly line production plane layout;
3 Determine the need for workers, reasonable Number of people;
④ Selection of reasonable means of transportation;
⑤ Layout of assembly line production;
⑥ Formulation of the standard plan of the assembly line indicator chart;
⑦ Evaluation of the economic effects of the organization of the assembly line.
Methods/Steps
Calculating the beat of an assembly line
The beat of an assembly line, an automated assembly line, is the time interval between the sequential production of two identical products. It indicates the high or low productivity of the assembly line and is the most important working parameter of the assembly line. The formula is as follows:
r=F/N
Which: r - the beat of the assembly line (minutes / pieces), F - the effective working time during the planning period (minutes), N - the planning period of the product output (pieces). Here: F = F0K, F0-planning period system working time (minutes), K-time utilization factor.
Determine the coefficient K to consider such factors: equipment repair, adjustment, replacement of mold time, workers rest time. General K take 0.9-0.96, two-shift working time K take 0.95, then F is:
F = FOK = 306 × 2 × 8 × 0.95 × 60 = 279072 (minutes)
Planning period of the product output N. In addition to the production outline should be based on the production of output, should also take into account the production of unavoidable scrap and the number of spares. the number of spares in the production should also be taken into account.
When the production line, production line manufacturing on the processing of small parts, the beat is only a few seconds or tens of seconds, the parts to be used in batches of transportation, the sequence of production of two batches of the same products between the time interval is called the rhythm, which is equal to the beat and the product of the transportation batch. The assembly line to take the batch transport products, if the batch is larger, although it can simplify the transportation work, but the assembly line in the work in progress to increase the amount of occupation. So for the large amount of labor, the weight of the piece, the value of the product should be used to transport a smaller batch; on the contrary, the batch should be expanded transportation.
Synchronization of processes, calculate the workplace (equipment) needs
After the assembly line of the beat is determined, according to the beat to regulate the process, so that the time of each process and the assembly line of the beat is equal or an integer multiple of the proportionality of the relationship between the work is known as the synchronization of processes. Process synchronization is a necessary condition for the organization of the assembly line, but also to improve equipment load and labor productivity, shorten the production cycle of an important method.
The measures for process synchronization are:
① Improve the productivity of equipment. Can be modified equipment, change the type of equipment, processing several parts at the same time to improve production efficiency;
② Improvement of process equipment. The use of fast mounting fixtures, molds, reduce the time of clamping parts;
3 Improvement of the workplace layout and operating methods to reduce the time of auxiliary operations;
4 Improvement of the work of workers proficiency and efficiency;
5 Detailed consolidation and decomposition of the process. First divide the process into several parts, and then recombine the process according to the beat to achieve the requirement of contemporization, which is the main method of assembly process contemporization.
After the process synchronization, according to the newly determined process time to calculate the amount of equipment needed for each process, it can be calculated using the following formula:
m(i)=t(i)/r
where: mi - the ith process required for the number of workplaces (number of units of equipment), ti - the ith process of a single piece of time fixed. process of a single piece of time quota (minutes) including the time of workers on the conveyor belt to pick up and put down products. In general, the calculated number of equipment is not an integer, the number of equipment taken is greater than the calculated number of neighboring integers. If the load on a piece of equipment is large, the load should be reduced by transferring part of the process to other equipment or by increasing the working time.
Calculate the number of workers needed, reasonable workers
Industrial assembly line, painting line after the number of processes to determine the number of workers on the assembly line can be calculated.
(1) to manual labor and the use of hand tools based assembly line worker needs can be calculated as follows:
pi = sigwi
In the formula: Pi - the ith process worker needs (people), g - the daily work shift, si - the ith process number of workplaces, g - the daily work shift, si - the ith process number of workplaces, si - the ith process number of workplaces, si - the ith process number of workplaces, si - the ith process number of workplace. i process workplace number, wi - the number of people working at the same time in each workplace (people)
p=Σm ?i=1pi=Σm ?i=1sigwi
Here P is the total number of assembly line operation workers (people).
(2) equipment processing-based assembly line worker requirements can be calculated using the following formula:
p=(1+b 100)Σm ?i=1Sig ?fi
where: b-percentage of reserve workers, fi-the ith channel
speed of conveyor belt on the assembly line Calculation of the length of the conveyor belt
The speed of the conveyor belt (V) can be obtained from the following formula:
V=s[]r(m/min)
In the formula, s table length of the product interval. From the above formula can be seen beat r for a fixed value, the product interval length s the larger, the conveyor belt running speed; s the smaller, V is also the smaller.
The selection of the product interval length should be determined according to the specific circumstances, the minimum limit of 0.7-0.8 meters, in order to take care of other reasons, but also to give additional length of grace.
The length of the assembly line conveyor belt can be calculated by the right formula:
L=mB+X
Which: L-conveyor belt length, m-the number of processes, B-process interval length, X-conveyor belt at both ends of the additional margin.
An assembly line layout design
The layout of the assembly line should be designed to ensure that the shortest route for the transportation of parts, production workers to operate conveniently, auxiliary services to facilitate the work of the department, the most effective use of the production area, and to take into account the interconnection between the assembly line. In order to meet these requirements, in the assembly line layout should be considered in the form of assembly line, assembly line within the workplace arrangement method and other issues.
The shape of the production line, automated assembly line has a straight line, right-angle shape, openings, rings, etc., as shown in Figure 2-1.
The arrangement of workplaces in the assembly line should be in line with the process route, and when the process has more than two workplaces, the arrangement of workplaces for the same process should be considered. Generally when there are two or more than two even number of the same kind of workplace, to consider the use of double row arrangement, they will be divided in the transportation route of the two cases. But when a worker to look after more than one piece of equipment, to consider making the worker to move as short a distance as possible.
The location of the assembly line involves the interrelationship between the assembly line, according to the processing of parts assembly required by the sequence of arrangement, the overall arrangement should seriously consider the material flow problems, thereby shortening the route, reduce transportation workload. In short, attention should be paid to a reasonable and scientific flow of production process space organization.
An assembly line standard plan to indicate the development of charts
An assembly line on each workplace according to a certain beat to repeat the production, so you can formulate a standard plan to indicate the chart of the assembly line, the production of assembly line production of the period of the amount of standardized work system and work procedures, etc., for the preparation of the production plan to provide a basis for the work of the preparation of the plan. Continuous assembly line of the standard plan to indicate the chart is relatively simple, as long as the provisions of the entire assembly line work time and procedures can be. Intermittent assembly line of the standard plan to indicate the chart is more complex, to provide for each process of the work of the workplace time and procedures.
Evaluation of economic effect indicators of the assembly line
The economic effect indicators of the assembly line are mainly, the increase in product output and growth rate, labor productivity and growth rate, the amount of working capital accounted for the amount of savings, the amount of reduction in product costs and the rate of reduction, additional payback period, the annual comprehensive savings and so on. In addition to the above quantitative indicators, but also consider some non-quantifiable indicators, such as labor conditions, environmental protection improvements.
Enterprises should be based on their own actual situation of single-species assembly line design, the design of the assembly line should be in line with the production requirements of the enterprise, can bring good economic benefits to the enterprise. Otherwise, the assembly line must be properly adjusted, redesigned or directly eliminated. Xingqiantian specializes in assembly line design for 13 years