GRULET'S SCREW FOR RAISING WATER.
The French Agricultural Machínery Company has recently made a very interesting application of the screw for raising water for submersion and irrigation, and, to our knowledge, it is the first of its kind.
It is only necessary to examine the accompanying cut and observe the dimensions of the machine (which was constructed according to plans of Mr. Grulet) to recognize the fact that we have here a really practical application.
The screw, which constitutes the principal peculiarity of the system, has six blades, with a pitch of 0.465 m. On making 210 revolutions per minute it is capable of raising about 435 liters (95 gallons) per second to a height of 1.2 m (about 4 feet). The shaft that drives it revolves in a bearing which is bolted to a cross piece that is affixed to the cylindrical chamber. This latter consists of a cast iron case that is easily taken apart, and of a strong cylinder of iron plate whose upper extremity is connected, by means of riveted angle iron, with the bottom of the sluice. In the interior of the cylinder there are two cones, whose bases embrace the hub of the screw in such a way as to obtain a continuous superposition of the layers of liquid, and prevent bodies in suspension from penetrating between the rubbing surfaces of the bearing. One of the cones is made of iron plate, and is connected with the principal cylinder by four radiating braces and small angle irons, and the other is cast in a single piece with the box of the pivot.
The rotary axis is guided above by two pillow blocks held by the cross pieces of a frame that is riveted to the sides of the sluice. Finally, this latter terminates in a hinged gate which regulates the flow of the water.
Two beams that rest upon the sides of a stream will suffice in most cases to support the entire affair.
The mechanical duty of the apparatus is estimated at about 65 per cent. In the apparatus put up by Mr. Grulet, the motive power is furnished by a portable 10 H.P. engine. The boiler is a return flame one, with movable fire place, and the steam cylinder has a diameter of 0.2 m. (8 inches) for a piston stroke of 0.3 m. (about 12 inches). Before the apparatus was finally put in place it was sent to the last exhibition at Carcassonne, where it attracted very much attention from visitors. Its great regularity in working was particularly remarked. This quality, and the simplicity of its construction and the ease with which it may be put in place, are valuable features in apparatus that are designed to be looked after by inexperienced persons, and to operate in open air far from repair shops.—Revue Industrielle.
GRULET'S SCREW FOR RAISING WATER.