Abstract: Fluid flow control devices such as drip irrigation or micro-sprinkler valves and emitter unit membranes are constructed of an elastomeric composition selected from the group consisting of (1) a halogenated butyl elastomer, and (2) a diene nitrile elastomer and mixtures of (1) and (2). An ethylene propylene diene elastomer EDPM can also be incorporated into the composition. Use of the compositions inhibits valve and membrane swelling that would otherwise occur when such valves and membranes are contacted by water sources comprising organic and inorganic impurities.

Abstract: A spiral chute device, especially for use in conveying seed materials to storage chambers. The spiral chute device is employed for guiding the seed material downwardly in the storage chamber to prevent the seed material from undergoing free fall which could lead to cracking thereof. The device is, preferably, suspended from the top wall of the chamber and has a hopper at the top with an upwardly opening spiral chute extending downwardly therefrom to near the bottom of the chamber. The device includes a center post telescopically engaged by a guide member at the center of the bottom wall of the chamber and the device can be moved laterally in the chamber by disengaging the lower end of the post from the guide member.