23-Ind-A2 Analysis and Design of Work · May 2014
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
National Exams — May 2014 — 98-Ind-A2 Analysis and Design of Work. Three-hour, closed-book exam (approved Casio/Sharp calculator only); any five of the seven questions constitute a complete paper and only the first five answered in the answer book are marked — all seven are solved below for completeness.
Reference texts: Niebel & Freivalds, Niebel’s Methods, Standards, and Work Design (13th ed.) — methods engineering and operation analysis, flow process charts, principles of motion economy, multiple-machine assignment, stopwatch time study, performance rating and allowances, predetermined time systems (MTM), work sampling, and job evaluation / wage-incentive systems.
Question text not reproduced: the examination questions are © Engineers and Geoscientists BC. Open the official past paper (linked at the top of this page) to read the question, then follow the worked solution below.
Methods engineering and work measurement attack cost from two complementary directions: methods engineering removes or simplifies work before it is ever measured, and work measurement then converts whatever work remains into an accurate, fair time value that drives every downstream planning and pay decision. Read together, the broad opportunity areas are: (1) elimination of unnecessary operations, motions and handling — the single cheapest saving, since work removed entirely costs nothing to perform; (2) combination of operations or elements that are currently split across separate stations or separate motions; (3) improved sequencing and routing to cut backtracking and cross-traffic; (4) workplace and plant layout improvements that shorten reach and travel distance; (5) tooling, jigs and fixtures that replace manual holding/positioning and cut setup time; (6) working-condition improvements (lighting, noise, temperature, housekeeping) that reduce fatigue and error; (7) balanced multiple-machine or multiple-operator assignments that remove idle time from whichever resource — person or machine — is currently underused (Question 3(iii)); (8) accurate, properly maintained time standards that support realistic scheduling, correct costing, and fair incentive pay, since a loose or tight standard is itself a hidden cost; and (9) reduced scrap and rework through better process and tooling design. Methods engineering supplies (1)–(6) and (9); work measurement, applied to the improved method, supplies (7)–(8).
A flow process chart records, step by step, everything that happens to a material, part or worker as it moves through a process, using the five standard ASME symbols: a circle for an operation (work is performed — a value-adding step), an arrow for a transportation (the item is moved), a square for an inspection (checked for quality or quantity, no value added), a capital D for a delay (the item waits before the next step), and an inverted triangle for a storage (the item is held under authorization, not merely waiting). Each line of the chart carries the symbol, a short description of the step, the distance moved (for a transportation), the time taken, and the quantity handled, so the whole sequence — operations mixed with the transportations, delays, inspections and storages that surround them — is visible on one page rather than scattered across separate records.
The summary form is a small table — one row per symbol type — giving the count, total time, and (for transportations) total distance for each of the five categories, placed at the top or bottom of the chart. It is what turns the chart from a record into a decision tool: a “before” summary and an “after” summary, placed side by side once a proposed method is charted the same way, show at a glance how many transportations, delays, and storages the proposed method removes and by how much total time and distance.
Main uses. The flow process chart is used to: (1) visualize an entire process route on one page, revealing hidden non-value-adding steps — excess transportation, avoidable delay, unnecessary storage — that are easy to miss when only the operations themselves are examined; (2) systematically apply operation-analysis questioning (can a step be eliminated, combined, resequenced, simplified) to every recorded step, not just the operations; (3) quantify the “before” and “after” cost of a proposed method change via the summary form, supporting a defensible economic case for the change; (4) estimate and cost material-handling and layout requirements, since distances and delay times on the chart translate directly into handling-equipment and floor-space needs; and (5) document and standardize an approved method for training and for future audit against drift.
Applying the operation-analysis checklist of part (i) specifically to a metal-cutting shop, the areas worth investigating are: (1) raw material specification — stock size, shape and metallurgy, to minimize the material removed (and therefore machining time) while still meeting the finished-part tolerance; (2) cutting parameters and tooling — cutting speed, feed rate, depth of cut and tool material/geometry, since these set both the machine (power-feed) time directly measured in Question 4(i) and the tool-wear/downtime rate; (3) work-holding and fixturing — jigs, quick-change chucks and fixtures that replace manual positioning, cutting both the load/unload element time and setup time between jobs; (4) machine and plant layout — sequencing machines to minimize part travel between operations, and choosing process vs. product layout appropriately for the batch size; (5) materials handling between machines — conveyors, chutes or powered transport in place of manual carrying, shortening the transportation steps identified on the flow process chart; (6) sequence and combination of operations — whether successive cuts can be combined on one machine (e.g. a multi-axis or CNC setup replacing several single-purpose machines) to remove intervening transports and delays; (7) multiple-machine assignment potential — whether the automatic (power-feed) run time on a given machine is long enough that one operator can be economically assigned more than one machine (the calculation performed in Question 3(iii)); (8) coolant, chip and swarf management — poor chip evacuation both slows the cycle (interruptions to clear chips) and accelerates tool wear; (9) in-process inspection method — gauging frequency and technique (e.g. the go/no-go gauge check of Question 4(i)), balancing quality assurance against added non-value time; (10) preventive maintenance scheduling — reducing the unplanned machine downtime that a multiple-machine assignment calculation must otherwise allow for; and (11) working conditions at the machine — noise, swarf hazards and lighting, which affect both fatigue allowance and operator safety.
