When refractory casting operations are conducted in the ferrous and non-ferrous metal, glass, Portland cement, refining, and petrochem industries, use of ASTM Test Method C 1445, Standard Test Method for Measuring Consistency of Castable Refractory Using a Flow Table, produces a numerical result that allows the operator to follow manufacturer’s recommendations or to reproduce the consistency of a particular castable between laboratories.

“A refractory castable can be thought of as a raw material,” says Robert Antram, staff engineer, Exxon Research and Engineering, Florham Park, N.J., and chairman of Committee C08 on Refractories. “It is not a finished product until mixed with water, placed, and cured. The refractory manufacturer and the cement manufacturer realize how important these final steps are to the success of a material. A good means of control, such as the flow table, can really improve the control of the casting step, and result in an improved final product.

“The ideal flow range for a particular castable can be quickly determined either by the manufacturer or the installer, and then used to control any casting operation,” says Antram, referring to the flow table method in C 1445. “It is important in the quality control both of the material itself and for the quality control of a casting operation. One of the questions invariably asked in the field is ‘How much water shall I cast with?’ The answer, up till now, is generally one of two things: a fairly wide range of water contents or the blithe statement, ‘as dry as possible to get the best possible properties.’ Neither has much real meaning, and certainly little control. It is much better to say ‘Cast this material at a flow range of x to y percent.’ If the water it takes to get you to a flow range of x to y percent is in the range of a to b percent, then you know everything is in good order, and you are controlling a good casting operation. If you are outside of these limits, then you need to investigate, because something is wrong.”

C 1445 was developed by a task group of Subcommittee C08.09 on Monolithic Refractories, representing refractory and cement manufacturers, and the refining industry. Members of academia provided some input.

For further technical information, contact Robert Antram, Exxon Research and Engineering, 180 Park Ave., Florham Park, NJ 07932 (973/765-2599; fax: 973/765-1463). Committee C08 meets October 19 at the Imperial Palace, Las Vegas, Nev. For details, contact manager Felicia Quinzi, ASTM (610/832-9738). //

Copyright 2000, ASTM