Compressor Inspection

The essential procedure in compressor periodic inspection is the hydrostatic pressure test. Unless otherwise specified in applicable standards, these tests must be performed at 1.5 times the operating pressure and at intervals not exceeding one year.

However, if the characteristics of the equipment or operational conditions do not allow for hydrostatic testing, non-destructive testing (NDT) methods defined in the standards may be used instead. In such cases, the periodic inspection report must clearly state this situation along with its justification. This requirement is specified in Article 2.1 – Pressure Vessels and Installations, paragraph 2.1.1 of the Work Equipment Regulation.

NDT Methods Used in Compressor Air Tank Inspections

Compressor air tanks may be inspected using the following non-destructive test methods:

• Visual inspection
• Radiographic and ultrasonic thickness measurement
• Magnetic particle testing
• Liquid penetrant testing
• Eddy current testing

According to the Pressure Equipment Regulation, Article 2.11.2, momentary pressure fluctuations must be kept within 10% of the maximum allowable pressure.

Safety Requirements

Compressor air tanks must be equipped with a safety device.
The safety valve must open before the pressure exceeds 10% above the maximum allowable pressure.

Steps in Compressor Periodic Inspection

• Visual inspection of the outer shell and welds for deformation or corrosion
• After isolating system connections, the tank is filled completely with water
• A hydrostatic test at 1.5 times the operating pressure is performed
• The pressure gauge and safety devices installed on the tank are checked
• After a 30-minute hydrostatic test, the tank and welds are examined for deformation, and the test is completed

Authorized Personnel

As stated in Article 2.1.3, periodic inspections of pressure vessels and installations may be performed by:

• Mechanical engineers
• Metallurgical and materials engineers
• Technical teachers (mechanical or metal departments)
• Mechanical technicians or senior technicians

If non-destructive testing is used, only personnel certified according to TS EN ISO 9712 may perform these methods.

Customer Preparation

Customers are informed in advance via email by İnter Sistem technical personnel regarding the preparations and required loads before periodic inspections.