JPS57143616A - Condition controller for pc steel wire - Google Patents

Abstract

PURPOSE:To control the condition of a steel wire efficiently by automatically tensing and elongating a steel wire for a press-tressed concrete structure as prescribed by using a hydraulic pressure signal and an elongation signal from a hydraulic cylinder which applies tensile force and performs the elongation, and performing automatic recording. CONSTITUTION:A tensile-force caluclating circuit 31, an elastic-force comparing circuit 32, an elongation comparing circuit 33, an output equipment 34, a recorder 35, etc., are provided. A hydraulic-pressure signal from a pressure detector 16B which detects the pressure of a PC steel wire 2 is converted by the tensile-force calculating circuit 31 into an tensile-force signal, which is compared by the circuit 32 with the upper and lower limit values of preset tensile force. An elongation signal from an elongation detector 19B which detects the elongation of the PC steel wire is compared with the elongation comparator 33 with the upper and lower values of elongation. Tht output signals of the circuits 32 and 33 are inputted to the output equipment 34, whic performs control over hydraulic pressure in a hydraulic cylinder and warning display upon occasion.