Stainless steel gas lines
Deliver laboratory gas safely, efficiently and cost-effectively.
5 steps of a gas line installation
1: GAS REQUIREMENT AUDIT
The first step in efficiently designing a gas installation is to conduct an audit of the gases required for each area. This audit is required whether it is for a new facility or a retrofit.
It is important to identify which gases are required per instrument, their purity, required delivery pressure, and the peak flow demand. These parameters are essential in determining critical details; from the size of the piping to the storage area required, and even the source in which the gas may be supplied.
Overestimating the pressure requirements can result in higher installation costs and reduced gas savings. This can result in residual contents left in cylinders or higher monthly rental fees on cylinders that are not required. However, underestimating the pressure requirements can cause an inefficient supply of gas to critical instruments or systems that impair their operation.
2: SELECTING A LOCATION FOR A GAS DELIVERY SYSTEM
There are specific storage and separation requirements for the areas in which compressed or cryogenic gases are stored and/or connected to a building’s gas delivery system.
These requirements vary by local code requirements, but as a minimum, are required to meet the relevant OHS standards, SANS-10260-1 and SANS 10263-22008. As a minimum, gas cylinders should be stored and secured in an upright position using brackets, chains, or straps in a well-lit and ventilated area, away from combustible materials, sources of heat, and ignition.
Gas cylinders should be organised according to their hazard type. Empty and full containers should be kept separately with the appropriate hazard notification signage as required.
3: PIPE SIZING AND FLOW CONSIDERATIONS
To determine the pipe or tube size for an application, the main point to consider is what the maximum required flow – for the specific gas – would be if all application points were flowing to their maximum at the same time.
The maximum required flow can be found by adding the individual use points. Apply a conservative safety factor to allow for growth of requirements of at least 20–50%. This will depend on what the future outlook is for the specific gas.
4: CHOOSING THE RIGHT GAS DELIVERY SYSTEM
A critical requirement for most laboratory gases is to maintain gas purity.
Therefore, the choice of materials of construction, their compatibility with the specific gas, and their purity level are critical.
Beyond the compatibility between the materials and gas, the design is also required to retain gas purity. From the inlet to the outlet, a system that is designed with either bar stock brass or 316L stainless steel components is more suitable than any forged components. Diaphragms should be composed of 316L stainless steel, with diaphragm seals of a metal-to-metal design.