PURPOSE: To enable to monitor a circulating condition and a circulating amount of steel balls and the like surely at all times by a method wherein a steel ball accumulating tank is divided into upper and lower chambers, which are free of contraction and expansion, and a plurality of spring type batchers are interposed between them in a circumferential direction.

CONSTITUTION: A scale of a spring type batcher 9 is set at zero under noload condition of a steel ball accumulating tank 1, subsequently, the steel balls are thrown into an upper chamber 1a of the steel ball accumulating tank 1 through a steel ball transporting pipe 2. The steel balls are accumulated in a lower chamber 1b sequentially and a connecting member 5 which is free of contraction and expansion is expanded by a weight thereof, therefore, indications of standard amount of steel balls in the lower chamber 1b and a specified amount thereof are maked on a spring type batcher 9. According to this method, whether the amount of steel balls circulating through a circulating path is normal or not may be confirmed surely from outside by monitoring the indicating mark on the batcher 9.