Hydrostatic Testing

Axenics specializes in hydrostatic testing DOT specifications 4B 260 and 4B 300 low-pressure, stainless-steel chemical canisters.

DOT Specifications

In order to meet Department of Transportation (DOT) Pipeline and Hazardous Materials Safety Administration (PHMSA)specifications, stainless steel cylinders must be tested every 3, 5 or 10 years by a DOT-approved hydrostatic testing facility. The timeframe for requalification testing is dependent upon the age and construction of the cylinder, the gas it contains, and the rating of the cylinder by the original equipment manufacturer (OEM).

DOT- Approved to Test, Repair & Rebuild

Our team of experts is qualified to test, inspect, certify, repair and/or rebuild low-pressure stainless-steel cylinders to meet the strict standards set forth by the DOT PHMSA, and in accordance with CGA (Compressed Gas Association) Methods for Hydrostatic Testing of Compressed Gas Cylinders. We hold the following DOT Stainless Steel Cylinder Approval:

  • RIN#: 1550, expires 6/19/2020
  • K#: KI33, expires 6/19/2020
  • M#: M6329, expires 3/9/2020
  • Cylinder Type: 4B260 + 4B300

Equipment Used

Axenics uses a state of the art hydrostatic tester to perform requalification test. The stainless steel cylinders are examined for leaks, and the overall integrity of the unit is assessed. Axenics’ hydrostatic tester measures the rate of expansion of the tube under water pressure, and determines whether the unit can safely hold the amount of pressure it is rated for.


Avoid Disasters

Hydrostatic testing is the most accurate way to test pressure vessels including pipelines, plumbing, and chemical cylinders for potential leaks. The hydrostatic requalification testing process is critical for preventing outdated containers from rupturing due to loss of structural integrity.

Avoid Penalties

Our highly-qualified testers use a simple and accurate testing process to help chemical, industrial, and other companies involved in transporting hazardous materials to avoid potential penalties and dangers associated with transporting outdated and/or weak cylinders.

Hydrotesting Q&A

What is hydrotesting?

Hydrotesting, also called hydrostatic testing, involves checking a canister, vessel or component to determine its integrity by measuring the rate of expansion using water pressure. The test will evaluate the strength and durability of welds to ensure that they can withstand extreme pressures and loads when the product is placed into operation. It can also be used to determine just how much pressure the vessel can withstand before failing.

What is hydrotesting used for and why is it required?

Any type of equipment that will hold products such as water, gas or chemicals that has undergone repair work can be hydrotested before being placed back into service. So storage tanks, pipelines, and even fire extinguishers can be hydrotested. For some canisters and pipelines, hydrotesting will be required in accordance with the Department of Transportation’s (DOT) Pipeline and Hazardous Materials Safety Administration (PHMSA) standards to receive recertification. Hydrotesting recertification may be required every 3, 5, 10 or 12 years.

How do you hydrotest a pressure vessel?

Dye is placed into water, or another liquid, as the water is pumped into the cylinder or pipe. The pressure inside the cylinder will rise to a specified level and then be set at that pressure for a certain length of time. The hydrostatic tester will measure the pressure expansion rate as technicians will look for any leaks or component failures.

How do you determine the hydrotest pressure?

The hydrotest pressure will be specific to the type of vessel that will be experiencing the testing as well as its components. The pressure can go up to 1.5 times the designed working pressure, or the pressure should not exceed the yield strength (the amount of stress toward the vessel where it begins to deform) of the test temperature. DOT vessels and canisters will have a certification rating marked on them regarding pressure limits.

How can hydrotesting help avoid disasters?

Vessels can crack, leak or even explode when going through high pressures, loads and other stresses. These situations can cause terrible disasters that can impact the health and safety of workers in an OEM manufacturing facility. It can also create environmental hazards if caustic or flammable liquids escape. Hydrotesting ensures that rebuilt or repaired vessels are up to quality standards and meets recertification. Hydrotesting can also help companies avoid costly fines and penalties.

Where can I hydrotest my tank or canister, and can testing be outsourced?

Hydrotesting tanks and canisters must be done at a certified hydrostatic facility that is compliant with all DOT PHMSA requirements. The facility may be certified to test one rating type of canisters or several different canister ratings. An OEM manufacturer can obtain certification to perform hydrotesting on their own. Yet it may be in their best interest to outsource the work as companies can save money on labor and equipment purchases. Also, if the testing doesn’t meet DOT recertification standards, the company can face penalties as well as place their workers at risk from cylinder or pipe failure.

What’s the difference between a hydrotest, a service test, and a pressure test?

There are many terms that you will hear when it comes to testing storage containers and cylinders. Axenics has taken the most used terms and provided explanations so you will know the difference and be able to get the right testing performed.

  • Hydrotest: tests the integrity of the tank under high pressure to measure how much it expands.
  • Service test: places the cylinder or vessel through regular operational testing to ensure it works effectively.
  • Pressure test: testing the cylinder or container to check for leaks, cracks and other possible issues.

Learn more about hydrotesting by contacting Axenics. We have state of the art hydrostatic testing equipment and are a certified and approved DOT testing facility.

Do you have low-pressure canisters that need to be requalified?

Please contact us to discuss your specific needs.

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