CNC Plasma Cutting: Water Table vs Downdraft Table

Plasma Cutting: Water Table & Downdraft Table, Which One Is Better?

The water table is the first choice for most mild steel cutting workshops. http://am.co.za/ In all our CNC Plasma Cutters, we only recommend water table and we will not provide downdraft cutting table for our plasma or oxy-fuel cutting machine.

Recent economic conditions have forced most industries to investigate innovative ways in which to cut costs. http://am.co.za/ Metal cutting workshops can trim their expenses in a variety of ways, http://am.co.za/ such as using a water table for ventilation within the workspace as opposed to using a downdraft table which is traditionally associated with fulfilling this need.

The Difference:

Whilst water tables have a more limited range of applications, downdraft tables are a lot more versatile. http://am.co.za/ This is to say that water tables are generally used just for plasma and oxy-fuel thermal cutting on mild steel. http://am.co.za/ By contrast, downdraft tables can be used for a greater variety of applications such as cutting a wide range of materials.

Another element that differentiates water tables from downdraft tables is the manner in which they process the fumes caused by the cutting. Downdraft tables pull excess particles and fumes through a perforated table and send them through a filtering system. http://am.co.za/ The implication of this way of ventilation is that you will need to change the downdraft table's filter every time you change the material that is being cut. This is due to the fact that different materials require different filter settings. http://am.co.za/ For example, if an operator wants to cut stainless steel, he would first have to change the filter in the downdraft table to one that will capture hexavalent chromium.

Plasma Water Cutting Table — Water Table build by
O.C.T. Engineering

Water tables, on the other hand, do not utilise any filters or fume collectors. Rather, water tables eliminate particles and fumes by employing the power of the kinetic energy of the stream of molten metal and gases. For example, in plasma cutting the water of the water table acts like the filter with all of the molten metal, gasses and fumes being pushed into the water instead of the atmosphere. It is important to bear in mind, however, that whilst the water table gets rid of smoke and dust as well as noise and sparks, it is only compatible with plasma and oxy-fuel thermal cutting. This is because with metals like aluminium, there is a possibility that gas can build up under the aluminium plate and between slats on a water table which, in an extreme, can even cause an explosion.

The Verdict:

Whilst downdraft tables do offer more versatility in terms of the materials it can cut, water tables are more suited to the general workshop. http://am.co.za/ This is because water tables are much less expensive than downdraft tables, http://am.co.za/ is more straight forward and user friendly and consumes much less energy. Although the water table and the downdraft table's cost is similar, it is the fume collector, http://am.co.za/ ducting and filters that push the downdraft table's price up by more than 40%. This makes the water table the first choice for most mild steel cutting workshops. In all our CNC Plasma Cutters, http://am.co.za/ we only recommend water table and we will not provide downdraft cutting table for our plasma/oxy-fuel cutting machine.