The system that gives you control over the gas supply
Safe Environment and operating conditions

• High Pressure Gas cylinders are located and placed in one place under one roof which facilitates easy and safe delivery, handling and removal.
• Heavy gas cylinders containing toxic gases under high pressure can involve great risks. The risk of incidents/accidents is reduced as there is no need to handle high pressure gas cylinders inside the work area. Only low pressure equipment and small gas quantities are present in the work area.
• The handling of high pressure cylinders and the connection of toxic gases should be carried out by trained staff. If a problem with leaking gas should occur ventilation is essential. This is especially important while handling inflammable and toxic gases.
• The work place can be designed more effectively.
• Outlets positioned at every point of use are convenient and easy to use.

Improved operating economy

• A continuous “on tap” gas supply to each work station means less wasted time and fewer unplanned disruptions for changing gas cylinders.
• Fewer and larger gas cylinders which together supply all points of use.
  This means more effective emptying of the cylinders which in turn give lower costs for gas and cylinder rental as well as transport charges. In addition the store monitoring and purchasing can be centralized and rationalized.

The increasing use of chemically reactive gases and the great demands made on purity at the points of use have also contributed towards this trend. Welding methods have been developed which provide advantages with assembly in confined areas and which make it possible to join stainless steel systems while still maintaining a level of cleanliness and finish. Stainless steel is also chosen purely for aesthetic reasons or where the environment can give rise to corrosion. The selection of components for a gas supply system is always based on the chosen gas quality.

Top

Selection of material of construction

This is determined by the gas to be distributed, by its quality requirement and the level of contamination that can be accepted in the gas. The inner surface finish of components is one of the critical parameters and relates to the final purity of the gas at the point of use. A better surface finish will make the pipe system easier to clean and greatly reduce the chance and risk of particles being released into the gas stream.

Copper

Final pressure and free gas volume in the canister will however be governed by the vapour pressure limitations of gas components in the canister. Specially designed Pressure Regulators with very low flow rates for calibration purposes will be required along with these canisters and are also available.

Top

Stainless steel

Over the last few years, stainless steel has become the number one choice of material for pure gas applications. Stainless Steel can be supplied with a very good surface finish and can easily be cleaned.

Distribution and storage

• A storage area for the gas cylinders, with adequate ventilation and lighting, well isolated from the other work areas, but nearest to the points of use is required.
• Connected gas cylinders are placed in a separate area, preferably in adjacent to the access area. Avoid transporting gas cylinders indoors.
• The gases are stored (separately) according to fixed directives depending on their physical characteristics.
• Ventilation is provided based on safety requirements regarding the amount and type of gas used.

Gas cabinets and pipe systems

• Separate gas cabinets should be used for corrosive gases and toxic gases.
• When using extremely dangerous gases, it is recommended that flow control and emergency cut-off and safe venting arrangements are considered.
• Routing and laying of gas pipes shall be so that the risk of mechanical damage is eliminated and that, as far as possible, through areas where any leaking gas causes as little damage as possible.
• To maintain the purity requirements and to produce a tight gas system automatic computer controlled pipe welding equipment is used. All welding is carried out using internal and external shield-gas purging, which results in a clean and bright joints.

Top

Detection and alarms

• The need of detection shall be assessed. Regard should be taken to future requirements concerning types of gas and suitable flexibility to avoid unnecessary costs at a later stage.
• The possibility of an auto-stop if a leak is indicated. This can be achieved using detection equipment.
• The need of an alarm to an operating centre and/or an evacuation alarm within a certain area is to be assessed.

Testing

Pressure testing according to applicable standards are carried out and a protocol is established. A complete system is blown clean and analyzed to determine the humidity and oxygen content. Helium leak detection test is another option to guarantee a leak tight system. A certificate of tightness is drawn up.

Documentation

Before a gas supply system can be regarded as completed and is handed over for start-up it is documented.

A complete set of documentation comprises:

• Layout document (shows the entire supply systems design and positions in respective buildings).
• System specification including equipment list.
• Technical information covering all components.
• Spare part lists.
• Pressure testing protocol.
• Analysis certificate where applicable.
• Tightness certificate where applicable.
• Operating and servicing instructions.

Top