ISO 8643:1997, Earth-moving machinery - Hydraulic excavator and backhoe loader boom-lowering control device - Requirements and tests

This International Standard establishes uniform requirements and test procedures for boom-lowering control devices fitted on boom-lift cylinders to control the rate of drop in the case of a hydraulic line failure or rupture.This International Standard applies to boom-lowering control devices on hydraulic excavators and the backhoe part of backhoe loaders, when used for handling and lifting objects.