Rosin & Turpentine Factory Nahan is one of the two Rosin Factories under the H.P. State Forest Corporation. This was established during the year 1949, with M/s Gopal Singh & Sons as Managing Agents under an agreement drawn during the erstwhile Sirmour Darbar. From the year 1957-58 to 1958-1959 the overall control of the factory was transferred to the Industries Deptt. of H.P.and from 1.4.1959 the administrative & financial control of this factory was handed over to H.P. Forest Deptt. On 1.4.1974 the management of this factory was handed over to H.P. State Forest Corporation and is continuing so till date.

                           The resin contained in  about 400 Tins (7.2 Tons.approx.) is emptied in to the Resin Pit. During winter resin is a bit hard to work, so 100-200 Litres of Turpentine Oil is mixed to dilute this resin. The Screw Elevator lifts this resin along with sakki (pine needles, bark pieces & other foreign particles) to the mixing Vat. The capacity of the Mix Vat is 350-400 tins i.e. about 7.2 Tons. of resin. The resin is heated indirectly in this vat by passing steam through copper coils for 4 to 6 hours to melt the resin in it. The temperature is maintained upto 95⁰ Celsius. 600-1200 Litres of Turpentine Oil (depending on the quality of resin) is also mixed in the mixing vat. 5 kgs. Common Salt is added. The molten resin is then stirred with Iron arms mechanically. The molten resin is then passed through 40-mesh (in one square inch, there are 40 openings ) stainless steel wire net to remove bigger impurities like pine needles, bark pieces etc.

                         In the Distillation Kettle, the resin is cooked for 1-2 hours by indirect steam at pressure of 10kgs/cm . In Distillation Kettle, the molten resin remains inside the copper tubes and steam remains in the outside. In this process the Turpentine Oil and moisture present in the resin get evaporated   and condense in the condenser. T.Oil is collected in a T.Oil Separator.

                          The Rosin left in the distillation kettle is taken out at 165⁰ Celsius & collected in trolleys ,wherein about 100-200 grams of Oxalic Acid ( depending on the quality of resin) is mixed to increase the transparency / shine of Rosin. This Rosin is then packed in Tin Patra Barrels of 200 Kg. capacity.

                         These items i.e. Rosin and Turpentine Oil are also called Gum Naval Stores in American markets. This is based on the historical use of rosin for making boats water proof.

                                    General Manager,
                                    Rosin and Turpentine Factory,
                                    NAHAN –173001
                                    HIMACHAL  PRADESH
                                    Tele fax :  1702- 224019, 225478
                                    E-mail   : vanpraniharsh@sancharnet.in
                                    For Tenders : http://himachal.nic.in/tender.htm

Rosin is a brittle, faintly aromatic solid, which may be transparent or slightly translucent and possesses a glassy fracture. It is insoluble in water, but soluble in many organic solvents including alcohols, ethers and esters, and aliphatic, aromatic and chlorinated hydrocarbons.

                   All rosin is purchased on a colour basis, which varies from pale amber to black. The lighter the colour, the more valuable the rosin.

                 The procedure for sample and colour grading is fairly simple: a portion of rosin is formed into a cube of 7/8 inch(22mm) sides. This cube is placed inside the cabin of Lovibond Tintometer and Standard Colour of the specific grade is compared with that of the cube. The standard  colour is obtained by combination of glass slides of different shades  of Red, Blue and Yellow . This is as per the procedure laid down in IS 553:1984.

Technical specification of various grades of Rosin.

X - Extra White, WW – Water White, WG – Window Glass,
N–Nancy, M – Mary, K – Kitty, H – Harry, D – Dark & B – Black.

                           Turpentine, like rosin, is a very versatile raw material. At one time turpentine was a very important solvent and thinner for paint and varnish. In recent years this use has declined drastically, both on account of substitution by cheaper petroleum-derieved solvents (white spirits) and because of the growth of paints based upon polymeric latexes. Whereas in the past turpentine was used mostly in its natural form, today most turpentine is further processed into its various constituents before use. Since turpentine is mainly used in its fractionated form, the major fractions of turpentine are given below:

Specifications of Turpentine Oil- Grade-II