Generally large furnaces are non Tilting in Type and use bottom pouring methad to take out the Molten Metal through the Tap Hole. When the Tap hole needs to be opened the same is done with the help of a High Frequency Induction Welded Low Carbon Mild Steel Tube which can sustain 750 PSI Pressure without leaking of Suitable Size 8mm NB, 15 mm NB or even 25 mm NB in certain Cases. Oxgen at high pressure is injected through these tubes into the Tap Hole and the molten metal starts flowing. Depending on the type of Ferro alloy or Steel Plant or Copper or Zinc Smelter the Consumption of the Pipe is determined. This lance pipes are basically used to open the Tap holes of Bottom Pouring Furnaces.
No IS-1239 and IS-10577/82 is not the same. IS-10577/82 is actually the IS which specifies the requirements of a Lancing Pipe. IS-1239 is primarily meant for Water Tubes.
No NB Stands for Nominal Bore. It is not the same as OD (Outside diameter). NB is a Nomenclature and is basically the name assigned to that particular Pipes. Please refer to the IS-10577/82 given in our Products to get the correct Outside diameter and Thickness of each pipe Category. As per the IS the pipes are classified by their OD (Outside Diameter) and not ID (Inside diameter). This is because the pipes need to be threaded at both ends or at one end as such the OD cannot vary beyond a certain range as specified in the IS.
In our opinion one should buy in terms of Metric Ton rather than in terms of Meters/Pieces. This is because when one is buying in terms of meter then it is not possible to check the thickness of each and every pipe. Neither is it possible to count the exact numbers of bundles nor is it possible to verify what is the number of pipes in each bundle. Last but not of the least importance it is not possible to measure the lenght of each pipe because generally the pipes are supplied in bundle which appear like Broom Sticks (Not in our case as tolerance in lenght is 0.1 Meters) . Looking at the reasons stated above our Company prefers to supply these pipes in terms of Metric Tons. However should a Customer insist on buying in terms of Meters we want the Weight per meter as stated in the IS to be mentioned in the purchase order so that there is no scope for foul play and materials are supplied strictly as per the Indian Standards or British Standard as the case may be.