Stainless Steel Nozzles
Spray nozzles are manufactured from different materials, including brass and plastics as well as the "specialist" materials such as Hastelloy, but one of the most common materials are the various grades of stainless steel.
The factors governing the right spray nozzle material choice are:
This will have a large bearing on the type of material to be used, but 303. 316 and 316L stainless steel nozzles have a temperature of up to 430 º, whilst plastic (PTFE) material has a rating of only 150º
Spray fluid will cause abrasion of the orifice and swirl chamber component of the nozzle. Harder wearing materials should always be considered, but the cost of purchase and the time scale of replacement should always be considered. (Cost of ownership). Stainless steel spray nozzles should always be a serious contender when considering this issue, as these nozzles provide a balance between frequency of replacement and cost.
A non neutral spray fluid will always attack the spray nozzle. An understanding of the fluid specification must be obtained before a recommendation can be made on the right spray nozzle and orifice material.
Stainless steel spray nozzles are in the middle of the desired nozzle material to be recommended. Plastic spray nozzles are excellent, but can only be used at the lower temperature range, whilst the more specialist materials such as Hastelloy offer a combination of good corrosion resistance and higher temperature tolerance.
Cost of ownership
This factor must always be taken into consideration. Whether to frequently replace nozzles at the lower cost range or whether to introduce more costly nozzles with better attributes to the application. We at IC Spray Ltd can offer a complete range of nozzles in most materials and can offer you alternatives that will suite both the application and your budget.
Most grades of stainless have their place in spray nozzle applications, the most common being stainless steel 303 (DIN description 1.4305) and 316 (DIN description 1.4401) grades. Other grades are used depending upon the application, such as 316L, a harder material, less prone to product attack and may be used in food, cleaning in place and pharmaceutical spray applications.
There is naturally a cost implication and a large proportion of spray application are capable of using 303 grade, which is easier to manufacture and therefore lower in cost than the 316 equivalent.
Stainless steel nozzles can be used in conjunction with other materials as such as sapphire, tungsten carbide and ceramic orifices to produce a much longer lasting spray nozzle, especially where the spray material is abrasive.