The air compressor’s air tank rusted and exploded. Is it still covered under warranty now that the warranty period has expired?

The Basic Relationship Between Gas Storage Tank Explosions and the Warranty Period

Air compressor air receivers are classified as pressure vessels and are typical types of special equipment. As a general rule, the warranty period represents the timeframe during which the manufacturer guarantees product quality. Once the warranty expires, the manufacturer typically no longer assumes any obligation for free repairs or replacements. However, when an air receiver ruptures due to corrosion, resulting in a serious safety incident such as an explosion, liability cannot be determined solely by whether the warranty has expired; instead, a comprehensive assessment of multiple factors is required.

Principles for Determining Liability in Accidents Involving Overdue Equipment

In the event of a gas storage tank explosion occurring outside the warranty period, liability determination typically hinges on the following key factors:

• Does the product have any inherent defects?If a professional appraisal can establish that the gas storage tank has inherent defects in its design, manufacture, or materials that fail to comply with mandatory national standards, and that such defects were the root cause of the explosion, the user shall be entitled to hold the manufacturer liable under the relevant product quality laws and regulations, even after the warranty period has expired.
• Are daily maintenance and inspections conducted in compliance with regulations?As a type of special equipment, gas storage tanks impose on their operators statutory obligations to perform routine maintenance, conduct periodic drainage, and submit applications for scheduled inspections. If an explosion is caused by prolonged failure to drain the tank—resulting in severe corrosion—failure to undergo annual inspections as required, or unauthorized operation, the liability typically rests with the operator.
• Are the safety accessories effective?Whether safety valves, pressure gauges, and other safety accessories have been properly calibrated and functioned as intended is also a key consideration in accident investigations. If the failure of such safety devices results in an overpressure explosion, the individuals responsible for their maintenance shall bear the corresponding liabilities.

Analysis of Common Causes of Explosions Due to Rusting

Rust forming inside a gas storage tank, which can ultimately lead to an explosion, is typically closely linked to the following lapses in routine maintenance and management:

• Failure to drain condensate in a timely mannerCompressed air from the air compressor contains moisture. If you fail to develop the habit of regularly draining the condensate from the bottom of the air tank, moisture will accumulate over time, leading to severe corrosion and thinning of the tank’s interior.
• Harsh working conditionsIf the exterior of a gas storage tank is exposed for extended periods to humid, corrosive atmospheres without corrosion protection, external rust can weaken the vessel’s pressure-bearing capacity.
• Overdue Service and Uninspected: Gas storage tanks that have reached their design service life or have failed periodic inspections for special equipment may have experienced metal fatigue and corrosion to such an extent that they can no longer safely withstand normal operating pressure.

Recommendations for Response and Handling Following an Accident

In the event of a gas storage tank explosion, it is recommended to follow the following standardized procedures:

• Secure the scene and report it.Immediately activate the emergency response plan, rescue the injured, and secure the accident site. Following an incident involving special equipment, it is mandatory to promptly report the incident to the local authorities responsible for the safety supervision of special equipment and to the emergency management department in accordance with applicable regulations.
• Apply for professional certificationA qualified special equipment inspection agency or a third-party forensic appraisal institution shall conduct a technical investigation into the cause of the explosion to determine whether it was due to a manufacturing defect or improper use and maintenance.
• Seeking professional legal supportGiven the complex legal relationships involved, including the Special Equipment Safety Law, the Product Quality Law, and tort liability, it is advisable to promptly consult a professional attorney and, based on the expert appraisal findings, safeguard your legitimate rights and interests in accordance with the law.

Daily Management for Preventing Safety Accidents in Gas Storage Tanks

To prevent similar accidents from recurring, enterprises must strictly implement the safety management system for special equipment.

• Establish a stringent daily drainage procedure to ensure the inside of the gas storage tank remains dry.
• Regularly verify the calibration of safety valves and pressure gauges to ensure that safety accessories are sensitive and reliable.
• In strict accordance with relevant regulations for special equipment, submit applications for periodic inspections on schedule, and strictly prohibit the operation of equipment that is faulty or has exceeded its service life.
• Improve the operating environment of gas storage tanks, and, when necessary, apply an external anti-corrosion coating or install rain‑ and moisture‑proofing facilities.