The use of time study, method study and GPS tracking in improving operational harvest planning in terms of system productivity and costs

[摘要] ENGLISH ABSTRACT: This study aims to quantify the benefits of implementing an operationalharvesting plan in forest harvesting operations. This is to be achieved bycomparing productivity and costs from unplanned and planned harvestingoperations. The study was conducted on a Pinus radiata plantation ownedby Mountain to Ocean Forestry Company (Pty) Ltd (MTO) located near thetown of Grabouw in the Western Cape Province of South Africa.MTO conducts harvesting operations using semi-mechanised tree-lengthharvesting systems. A wheeled H67 Clark Ranger cable skidder is used toextract tree-lengths from infield to the landing. Data was obtained bothmanually (work study) and from GPS tracking. Choking and dechoking datawas obtained through time and method studies. GPS tracking was used tomeasure travel loaded and travel empty times, as well as travel distancesand travel speeds. The aim of using both manual techniques and GPStracking was to obtain detailed and spatially accurate information about theoperation. The operating costs were estimated using South AfricanHarvesting and Transport Costing Model.Productivity of the newly introduced tagline system (45.97 m³/pmh) exceededthat of mainline system (37.85 m³/pmhh) by 26%. The unit production cost ofusing tagline system (R20.21/m³) was 10% lower than the unit productioncost of using mainline system (R22.54/³3). There were no benefits to begained from improving the level of skid trail construction by removal oflogging residue or cutting down stumps to as near the ground level aspossible. A combination of manual (time and method studies) data collectionand GPS tracking provided more detailed and accurate information on thesemi-mechanised harvesting system.

[发布机构] Stellenbosch University