Research indicates that the performance or condition of vertical injection molding machines may gradually decline over time. Many failures are preceded by certain warning signs, which are referred to as latent faults. Identifiable physical parameters suggest an impending functional failure, indicating that the vertical injection molding machine has lost the specified performance standards.

The failure rate of vertical injection molding machines as it varies over time is often referred to as the bathtub curve. The failure rate of vertical injection molding machines typically progresses through three stages: the early failure period, the intermittent failure period, and the wear-out failure period.

1. Early Failure Period

The vertical injection molding machine is in the early failure stage, with a high failure rate initially, but it rapidly decreases over time. This early failure period is also known as the磨合 period for mechanical products. The issues during this time vary depending on the product's, system's design, and manufacturing quality. The failures that occur during this period are mainly due to design and manufacturing defects, or improper usage environment.

2. Occasional Fault Period

The vertical injection molding machine is entering a period of occasional failures, during which the failure rate remains relatively stable and tends towards a constant value. Failures during this period occur randomly. Within the period of occasional failures, the failure rate of the vertical injection molding machine is low and stable, indicating a good state or normal operating period for the machine. This segment is referred to as the effective lifespan.

Faults during the occasional failure period are often due to poor design, improper use, and inadequate maintenance. Therefore, by improving design quality, enhancing usage management, strengthening monitoring, diagnostics, and maintenance, the failure rate can be reduced to a low level.

3. Wear-out Failure Period

As the vertical injection molding machine enters its later stages of use, the failure rate begins to rise. This is due to wear, fatigue, aging, and corrosion of the machine's components. If a major overhaul is conducted at the inflection point, when the wear-out failure phase starts, it can be done economically and effectively to reduce the failure rate.