Frequently Asked Questions

An ONIS device is a mechanical device that allows a single operator to spread a pipe without the use of tools. This is achieved through the use of eccentric shafts that facilitate the sliding movement of the gate, which can be equipped with various accessories.

Our manufacturing capabilities extend from 1’’ to 52’’, with a maximum pressure of 420 bars and a temperature range of -120°C to +650°C. Please refer to the product page for detailed specifications.

There is currently no industry-wide standard for the design and manufacture of mechanized line blinds or ONIS devices. Flange-to-flange dimensions are specific and are determined by calculation results based on the ASME VIII pressure vessel code.

As a general rule, at least one seal replacement should be considered on an annual basis. The frequency of change is dependent on the conditions of service, proper handling of the device, and its frequency of use.

The quality of the seals (dimensions and composition) is dependent upon the tightness of the ONIS device. For safety reasons, it is strongly recommended that only ONIS spare parts be used with ONIS devices.

The stress impact of an ONIS on pipes is much lower compared to traditional methods. Traditional methods typically require at least 1 inch (25 mm) for spreading the pipe, whereas the ONIS method uses just about 5 mm on average, which is five times less than what traditional methods need.

In the event of damage, only the four seals require replacement. ONIS advises that grease be injected into grease fittings at least once a year. No further maintenance is required.

ONIS devices are compatible with all types of products. Our devices are suitable for use with a range of fluids, gases, and other media, including those with particles or other suspended solids.

Yes, ONIS is definitely installed on pipes even if temporary installations could be imagined for very specific uses as mobile scrapping units.

ONIS devices can be supplied with integrated drain ports already drilled into flange or half bodies. The ONIS D3B device is designed with bleeder ports, which allows for the smallest dead volume of the valves and the line blinds.

The durability of ONIS line blinds has been proven over four decades, with some models installed in 1979 and still operational today. The reliability of ONIS line blinds is contingent on the environment, but their longevity is a testament to their quality.

A mechanized line blind is not a valve. It is a mechanical device that replaces the figure-8 or spectacle blind. A line blind is a real positive isolation device, and a valve is not. When a valve leaks, the leak goes downstream into the pipe. With a line blind, it is impossible because upstream and downstream pipes are physically separated by a steel plate. See the blog article “Positive Isolation Level of Pipelines” for more information.

We offer a range of safety solutions to meet your specific needs. From operator training to safety devices such as locks and pressure gauges, our team of experts can assist you in selecting the optimal combination of products from our HiSafe range, which is dedicated to reducing human factors.

As for a traditional blinding operation, safety requirements are the same. Only the way and the time requested to open the pipe to the atmosphere are very limited. Please have a look at the video “How to Operate a Line Blind” on the media center page.

This is not in line with the philosophy of ONIS products, as it does not provide positive isolation. In the event of a failure in the sealing of the slide gate, there is a risk of leakage from upstream to downstream, which would render the isolation unsafe. We kindly request that you review the section titled “The Different Levels of Isolation.”

Yes, a fire-safe design is available. While API 607 is not strictly applicable to ONIS line blinds, ONIS has its own first test bench and all tests have been conducted by a third party, SGS or DNV.

ONIS technology does not need any appreciation on the part of the operator. The ONIS design is set up in our workshop for the entire life cycle to guarantee tightness.