The principle of workshop assembly line layout can be summarized as: "Two observances, two avoidances". Two observances: counterclockwise arrangement, consistent entrances and exits; two avoidances: island layout and birdcage layout.
One of the ideal layouts for unit assembly lines is the petal layout
1. The principle of fluency: the organic combination of various processes, the principle of centralized placement of related processes, and the principle of streamlined layout;
2. The principle of the shortest distance: minimize the handling, the process cannot cross, and run in a straight line;
3. The principle of balance: the allocation of resources between workstations, and the allocation of speeds should be as balanced as possible;
4. Principle of fixed cycle: Minimize activities such as handling and passing non-value added activities;
5. The principle of economic output: adapt to the situation of minimum batch production, use the space as much as possible, and reduce the principle of ground placement;
6. The principle of flexibility: have sufficient adaptability to future changes, and the scheme is flexible. If it is a small batch of multiple types of products, priority should be given to "U"-shaped line layout, ring layout, etc.;
7. The principle of error prevention: the production layout should fully consider this principle as much as possible. The first step is to prevent errors from the hardware layout and reduce production losses!
-1-
Arranged counterclockwise
Arranged counterclockwise, the main purpose is to hope that employees can use one person to complete the work and realize one person with multiple machines. Completion by one person and multiple machines by one person require one employee to complete from beginning to end, so employees are dynamic, which is called "tourism work".
picture
Most of the operators are right-handed, so if they are arranged counterclockwise, when the employees perform the next processing operation, the jigs or parts are on the left side, which is inconvenient for the employees to work. This is exactly the purpose of counterclockwise— - The employee will go to the next station - the purpose of the tour is achieved.
-2-
Consistent entrance and exit
The same import and export means that the import of raw materials and the export of finished products are together. Why is the entrance and exit required to be consistent?
First of all, it is beneficial to reduce empty-handed waste. Assuming that the entrances and exits are not consistent and the operators use itinerant operations, then when a product is produced and a new raw material needs to be processed, the operator will walk from the finished product output exit to the raw material input entrance empty-handed (there is no material to produce) , this time is wasted.
If the entrance and exit are consistent, the operator can immediately get new raw materials for processing, thus avoiding empty-handed waste.
Second, it is conducive to the balance of the production line. Due to the consistent entrance and exit, the layout must present a shape similar to "U", which makes each process very close, thus providing the possibility for one person to operate multiple processes at the same time, which improves the flexibility of process allocation and thus achieves a higher production line balance rate.
—3—
Avoid silos
The island layout divides the production line into individual work units. The defect is that the units are isolated from each other and cannot assist each other.
picture
—4—
Avoid birdcage layouts
The birdcage layout often does not take into account the smooth flow of logistics and people. This kind of layout mistakenly encloses operators in the middle with machines, equipment or workbenches, resulting in unsmooth logistics, increased work-in-progress, and mutual support between units. It also becomes almost impossible.
—5—
petal layout
The petal-shaped layout is composed of multiple units, which is the result of the layout according to the principle of "two observances and two avoidances". This layout helps to improve the mutual assistance between the units, thereby improving the line balance rate. The petal layout is a necessary condition for "mutual assistance and collaboration".
picture
Mutual aid work is like a relay race on the sports field. In the handover area, strong players can properly make up for weak players. The same is true at work, and the operators between units have to pass the product like a baton.
If the operator in the front unit is delayed, the operator in the rear unit helps the front unit unload the product from the machine. This approach obviously relies on the "petal" layout as the premise.
—6—
"One flow" production line layout
According to the concept of lean production, in addition to the above two aspects, there are more important factors to consider. The goals pursued by lean production layout mainly include the following aspects:
(1) Minimize material handling costs;
(2) Effective use of space;
(3) Effective utilization of labor force;
(4) Facilitate information communication between employees, between employees and managers, and between employees and users.
In order to achieve the above goals, the best way is to arrange the equipment in a "U" shape to achieve "one flow" production. The "One-Piece Flow" production method refers to the rotation of small batches of products as much as possible during the production process, preferably the flow of a single piece.
It is the best way to reduce the amount of work in progress and is a good way to eliminate waste on the production line. Its basis is to make the processing line as streamlined as the assembly line, but at the expense of the utilization rate of non-bottleneck process equipment, so try to balance the production line and reduce the loss of equipment capacity.
—7—
"U" shape arrangement
The layout of the workshop assembly line is generally classified into the following two types: the traditional "one"-shaped production line layout (that is, the equipment is arranged in the order of processing) and the U-shaped layout.
With the popularization of lean production ideas, traditional production lines are more and more replaced by U-shaped production lines, because the layout of traditional production lines has the following disadvantages: when one person operates multiple devices, there will be "waste of walking", which increases labor intensity. At the same time, flexible adjustment of personnel cannot be realized.
picture
In a U-shaped arrangement, the production line is placed in a U-shape. The exit and entrance of an assembly line are at the same position. A processing location may contain several processes at the same time. Therefore, the U-shaped arrangement requires the cultivation of multi-skilled workers. It reduces walking waste and the number of stations, thereby shortening the cycle and improving efficiency, while also reducing operators and reducing costs.
