Small-batch, multi-variety production is suitable for adapting to market fluctuations. This production method allows for on-demand production based on market needs and customer orders, ensuring product quality, appropriate quantities, and timely delivery. In today's market economy, consumer preferences are becoming increasingly diverse, with a focus on unique, high-quality, and popular products. To expand market share, companies must adapt to these market changes.
The diversification of products has become an inevitable trend. We should recognize that new products are constantly emerging, which can lead to the premature obsolescence and waste of valuable products that have not yet been outdated. This phenomenon should be of concern. The goal is to adopt a production system that shortens lead times and reduces inventory.
1. Enhance adaptability to fluctuating demands.
- Small-batch, single-piece handling reduces job preparation time- Multi-skilled personnel and integrated chemical processes- Standardized quality control system- Universalization of equipment and tooling
2. Identify and highlight manufacturing issues and weaknesses.
Quality defects, equipment failures, workload imbalance, and extended production time.
3. Eliminate waste caused by improper production management, and reduce production management costs.
Due to improper production management, material delays, unnecessary machine changes, and increased indirect operations are all caused by improper production management.
4、Improve the adaptability to short lead times in manufacturing.
Eliminate stagnation (materials and information); reduce the number of intermediate products; synchronize.
—1—Features of small-batch, multi-variety production
1. Parallel processing of multiple types
Due to the customized nature of many products, different products have varying requirements, placing the company's resources across a wide range of options.
2. Resource Sharing
Each task in the production process requires resources, but the actual resources available are very limited. For example, equipment conflicts frequently occur during production, which is caused by the sharing of project resources. Therefore, it is necessary to appropriately allocate the limited resources to meet the project requirements.
3. Uncertainty regarding order fulfillment and production lead times
Due to fluctuating customer demands, the planned project milestones and the corresponding cycles for personnel, equipment, materials, methods, and the environment are often inconsistent, leading to unpredictable production cycles. This results in projects with insufficient time requiring more resources, thereby increasing the difficulty of production control.
4. Fluctuations in material requirements have led to significant delays in procurement.
Due to order modifications or changes, external processing and procurement are unable to meet the delivery deadlines specified in the original order. The risk of supply disruption is significantly increased due to small batch sizes and reliance on a single supplier.
—2—Challenges of small-batch, multi-variety production
1. Dynamic process path planning and deployment of virtual support lines: Emergency rush orders, equipment failures, and bottlenecks.
2. Identifying and Addressing Issues During Production: Before and During Manufacturing
3. Multi-layered Bottlenecks: Bottlenecks in the assembly line, bottlenecks in the virtual lines of parts, and how to coordinate their coupling.
4. Buffer Size: Either accumulate a large quantity or exhibit poor interference resistance. This applies to production batches, transfer batches, etc.
5. Production Scheduling: It is important to consider not only the bottleneck resources but also the impact of non-bottleneck resources.
Several challenges arise when implementing a small-batch, multi-product manufacturing model in practice, such as:
Due to the production of a variety of products in small batches, the complexity of mixed scheduling makes it difficult to meet delivery deadlines. The high volume of "emergency" overtime orders requires frequent changes in production priority, making it impossible to execute the original plan. This results in increasing inventory, but often leads to shortages of key materials and excessively long production cycles.
—3—Small-batch production of various types
1、The necessity of importing
Purpose: To shorten manufacturing cycles, reduce inventory, and adapt to fluctuating loads.
Conditions: Reduce job preparation time, increase frequency of material handling, implement quality control within each process, utilize improved manufacturing techniques to shorten production cycles, standardize work processes, implement a system for synchronized supply of components (component matching and Kanban management), flexible equipment, and a production plan that allows for small-batch production.
The ultimate goal is to achieve balanced production: simultaneous operation of multiple machines plus a single-piece production line that mixes machines with different types.
2、Are all types of production suitable for small-batch manufacturing?
This is not the case. Production must be aligned with sales volume, so high-demand models are produced in large or medium batches.
ABC analysis is derived from the PQ analysis method, which can clearly identify distinctions.
Production method:
A、For large-scale production
B、For medium-volume production
C、For small-scale production
Due to fluctuating market conditions, large-scale production often leads to increased inventory. Therefore, it is crucial to avoid this production method and instead adopt a daily production (small-batch production) approach to minimize inventory.
Balanced production
3、Advance manufacturing engineering work
(1) Establish a flexible production system
"Small-batch production of various types is a mechanism for high-efficiency manufacturing."
- Achieve rapid production with short preparation times.
Process-oriented quality control
Balanced production, standard operating procedures
Multi-skilled personnel
Universalize equipment and fixtures
(2) Shorten manufacturing cycle
This system allows for rapid delivery after order placement.
Eliminate stagnation (materials, information)
Improve component procurement synchronization rate
Reduce intermediate products in stock
Improve layout (reduce workstation size)
4、Specific measures for each stage of the process
(1) Automated application process
a、Reduce work-in-progress inventory
b、Reduce the production cycle time of the self-tapping machine.
c、Improve the operation of mechanical equipment
d、Carry out comprehensive and thorough maintenance of mechanical equipment.
e、Define the standard quantity of finished products.
(2) SKD process
a、Reduce the preparation time required for production changes.
b、Rapid preparation of the testing frame
c、Ensure that all residual materials from the process are completely eliminated.
(3) CTV overall assembly
a、Reduce the preparation time required for subsequent production runs.
b、Achieve complete balance in the line processing technique.
c、Repairing faulty equipment on the same day (do not postpone to the next day)
(4) Injection molding plant
a、Reduce the preparation time for subsequent production runs.
b、Logistics Seminar
c、Maintain appropriate inventory levels.
d、Conduct comprehensive and thorough maintenance of mechanical equipment
5、The role of indirect departments
Design Department
(1) Promote standardized design
(2) Shorten design cycles... Design specifications determine the efficiency and short design cycles.
(3) Enhance design completion rate
Procurement Department
(1) Strengthen collaboration among different departments.
(2) Shorten procurement cycle
(3) Re-evaluate the ordering process
(4) Separate instructions for ordering and delivery.
(5) Management of delivery periods and guidance from the supplier.
(6) Establish a material management and component deployment system for the manufacturing site.
Production Technology Department (including relevant departments)
(1) Fundamental technology development (including equipment and instrument development)
(2) Introduce production design methods
(3) Reduce the turnaround time
(4) Reduce manufacturing cycle time
(5) Train multi-skilled personnel
—4—Production of a variety of small-batch orders
The switching actions performed on-site can be categorized into the following 4 types:
Type 1: Switching between molds, tools, fixtures, and forming equipment.
This type of switching is commonly observed in mechanical fabrication plants and plastic injection molding plants, and it represents one of the most frequent switching actions.
This includes tasks such as replacing molds for injection molding machines, molds for machining centers, and tools for lathes and milling machines. Therefore, it is sometimes referred to as "mold changing" or "mold replacement." However, this terminology can be misleading to those unfamiliar with the process or beginners, as it implies that the process only involves changing the mold itself. Therefore, I believe that "switching" is a more appropriate and comprehensive term to use.
Type Two: Switching to Standard Changes
"Just as computers and numerical controllers are used in precision machining or chemical equipment, any change in the product requires a change in the standard and the re-setting of conditions. In fact, the most time-consuming and challenging part of the entire "switchover" process is the adjustment."
Form 3: Switching between components and materials in the assembly production line.
In the assembly production line, when products are changed, the corresponding components or materials must also be changed. This action
This is commonly referred to as "line change operation." Traditional line change operations typically involve stopping the entire production line after the last product is completed before performing the line change. For assembly lines with multiple stations, this approach results in significant downtime and considerable losses. However, if a sequential line change operation is implemented, regardless of the number of stations on the assembly line, the downtime associated with the line change will only be the time required to complete one station's cycle.
Type Four: General Preparation Work Before Manufacturing
This refers to the preparatory work that must be completed before manufacturing begins, such as reviewing drawings and assigning tasks before machining, as well as cleaning and organizing after work.
Four types of switching operations, although different in content, result in the same production downtime. However, most people focus primarily on improving the first type of switching operation, while neglecting the other three. In reality, improving these three types is not only easier but also saves a significant amount of switching time.
Source: Benchmark Lean