BS ISO 502:2015 pdf download – Coal — Determination of caking power — Gray-King coke test

BS ISO 502:2015 pdf download – Coal — Determination of caking power — Gray-King coke test 5 Apparatus 5.1 Furnace, horizontal electric, 50 mm internal diameter and 300 mm long, with one end closed and the other carrying a plug of insulating material which is bored centrally with a hole 25 mm in diameter. The winding of the furnace shall be such that the middle 200 mm is at a uniform temperature within ±5 °C at both 300 °C and 600 °C. Alternatively, the furnace may be constructed from an electrically-heated aluminium-bronze block, with one or several, bores of 25 mm diameter. The furnace shall be insulated and located in a cover of metal or other suitable material, and shall be equipped with a suitable thermocouple, lying above the retort tube when the latter is in position and with the junction at the centre of the furnace. An indicator shall be provided for showing the furnace temperature with an accuracy of ±5 °C. A suitable means of controlling the energy input shall also be provided to permit an increase in temperature at a rate of 5 °C/min. A multiple tube furnace to allow simultaneous determinations is convenient. The furnace may be of the fixed type or mounted on rails. Suitable furnaces are shown in Figure 2 and Figure 3. 5.2 Retort tube (see Figure 4), a heat-resistant glass or transparent silica tube, 20 mm internal diameter and 300 mm long, closed at one end, with a side arm, 8 mm internal diameter and 50 mm long, sealed in at a distance of about 20 mm from the open end. The tube shall be smooth and either of uniform bore or with a slight taper (19 mm to 21 mm) such that the open end is the larger. 5.3 Distance rod, with a flat disk at one end to assist in the packing of the coal and to indicate the free end of the coal sample in the retort tube. 5.4 Receiver and outlet tube A glass vessel of adequate size, suitably supported and attached to the side arm of the retort tube, fitted with an outlet tube leading to atmosphere or to a piece of small bore silica tubing at the end of which the gas leaving the receiver can be burned through Bunsen burner (in a fume cabinet) to ensure toxic fumes are burnt before venting to the atmosphere...