Pressure Testing

 

Quality assured hydrostatic testing

Those working in the oil and gas and mining industries know the importance of durable piping and tubing systems. Find leaks and test your system’s durability with hydrostatic pressure testing from Process Chemicals.
Process Chemicals is a WA company that offers specialised piping services for the growing needs of industry. We provide a turnkey service for your site’s hydrotesting requirements; from the setting up of piping test systems to the reinstatement and punch listing of complete piping systems. Contact us today to request a quote.

Vessel pressure testing

A vessel is filled with a nearly incompressible liquid – usually water or oil – and pressurised for testing and examined for leaks or permanent changes in shape. Water is commonly used because it is affordable and easily available, and is usually harmless to the system being tested. Red or fluorescent dyes may be added to make leaks easier to detect.
The test pressure is always set higher than the operating pressure to provide a factor of safety. This factor is typically between 110% or 150% of the designed working pressure, depending on the regulations that apply. Hydraulic fluids and oils may be specified where contamination with water could cause problems. These fluids are nearly incompressible and require relatively little work to develop a high pressure, meaning they will only release a small amount if any vessel component fails.

Pipeline testing

Hydrotesting of pipes and pipelines is performed to find defective materials that weren’t detected during initial testing. High pressure oil and gas pipelines that are buried deep underground are tested for strength. The working pressure is increased to at least 125% of their maximum allowable working pressure (MAWP) at any point along their length. Long-distance transmission pipelines may be designed to have a steel hoop stress of 80% of specified minimum yield strength (SMYS). This means that the steel can sometimes be stressed to SMYS and above during testing. Test sections must be selected to ensure that excessive plastic deformation does not occur.
The Australian standard AS2885.5 “Pipelines—Gas and liquid petroleum: Part 5: Field pressure testing” gives an excellent explanation of the factors involved.
Hydrostatic testing standards
All hydrostatic pressure testing and certification that is carried out is performed within our quality assurance guidelines and NATA regulations. This ensures that our reports, MDR’s and procedures meet the highest possible standards and project credentials.
Process Chemicals has an array of mobile testing equipment. We can conduct pressure testing in all plant and offshore environments and situations. These include shut downs, maintenance, commissioning and construction.

Our NATA Mechanical Testing Accreditation allows us to pressure test all plant piping and facilities, hydrostatically up to 120mPa and pneumatically to 20mPa.

Our scope of accreditation for Mechanical Testing is as Follows:

• Hydrostatic and Pneumatic Pressure of Piping
• Hydrostatic and Pneumatic Pressure of Hosing
• Hydrostatic and Pneumatic Pressure of Valves & Components
• Hydrostatic and Pneumatic Pressure of Cylinders and Pressure Vessels
• Hydrostatic and Pneumatic Pressure of Heat Exchangers

Supplementary services

Our staff are well trained and fully capable of managing and conducting this potentially hazardous aspect of a project and carrying out all pressure testing and supplementary works. In addition, we also possess the capability and equipment to provide a variety of supplementary project services:

• Test pack design, development and management
• High flow water flushing
• Line pigging
• N2 and air purging
• Desiccant air and vacuum drying
• High-pressure water blasting
• Hydraulic bolt tensioning

In addition to our supplementary services, we can also handle piping systems, from mechanically complete to piping system hand-overs with just one crew. This reduces time and costs associated with managing several sub-contractors.