23-Ind-A3 Facilities Planning · December 2014
Nivaar worked solution (AI-drafted; not reviewed by a licensed engineer)
Reference texts: Tompkins, White, Bozer & Tanchoco, Facilities Planning (4th ed., Wiley) — facilities design alternatives, material flow planning, activity relationships, machine space determination, material handling systems and the materials handling equation, computerized layout (CRAFT/CORELAP), and tool-crib centralization; Niebel & Freivalds, Niebel’s Methods, Standards, and Work Design (13th ed.) — assembly-line balancing (Ranked Positional Weight technique), balance delay, and production/scrap-allowance planning.
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.
In the context of facilities planning, materials handling is the movement, storage, protection and control of materials throughout the manufacturing and distribution process — from receiving, through every in-process move, to shipping. It is deliberately defined broadly (movement AND storage AND protection AND control, not movement alone) because a handling system must account for material while it sits between moves, not only while it is physically in transit.
The objectives of materials handling are: (1) increase efficiency of material flow by reducing distance, time and the number of handling operations (the unit-load principle: move the largest practical load per handling operation, Question 6(a)); (2) reduce handling cost, since handling adds cost without adding value to the product (Question 2(i)(c)'s cost-of-flow principle applies directly here); (3) increase usable production/storage capacity by minimizing the space consumed by handling equipment, aisles and staging; (4) improve working conditions and safety by removing manual handling of heavy, awkward or hazardous loads; (5) improve control over material — location, quantity and condition are known at every point, reducing loss, damage and misplacement; (6) promote productivity by keeping production and distribution personnel doing value-adding work rather than moving material themselves; and (7) improve customer service at the distribution end by making outbound material flow fast and reliable. These objectives are not independent: a handling system change that improves flow efficiency (1) very often also reduces cost (2) and improves safety (4) simultaneously, which is why handling-system evaluation weighs them together rather than optimizing any one alone.
The materials handling equation formalizes handling-method selection as a function of two inputs: Method $=f(\text{Material},\ \text{Move})$. The Material term captures WHAT is being handled — its physical, chemical and value characteristics (size, weight, shape, fragility, hazard classification, unit-load potential) — while the Move term captures the requirements of the movement itself: WHERE the move originates and ends, WHEN and how frequently it must happen, and any timing/scheduling constraint it must satisfy. The equation's point is that neither input alone determines the right handling method: the same material (e.g., a pallet of finished goods) may need a very different handling method depending on the move (a short, high-frequency in-plant transfer suits a powered conveyor, while a long, low-frequency yard move suits a forklift), and the same move (e.g., dock-to-storage) may need a different method depending on the material (a fragile, irregular load rules out equipment suited to a rigid, stackable one). Handling-system design (Question 1(ii)) is, in effect, the systematic process of evaluating this equation for every material/move combination the facility must support, rather than selecting equipment first and forcing the material and moves to fit it.
(a) Areas with the greatest opportunity for improvement. The areas that repay a facilities-design study first are those where the cost-of-flow principle (Question 2(i)(c), $\min\sum f_{ij}d_{ij}$) shows the largest concentration of cost: departments/areas with the highest material-flow VOLUME combined with the greatest DISTANCE or number of handling touches between them; areas relying on manual, repetitive handling (highest labour cost and injury/ergonomic risk per unit moved); congested or bottleneck work centres carrying visible queuing and excess work-in-process; storage and warehousing areas, which are often the least visible cost in a plant (poor space utilization and long put-away/retrieval travel rarely show up on a process chart the way production delays do); and shipping/receiving docks (Question 6(b)), since they are the single interface between the whole internal flow and the outside world and any inefficiency there is felt across the entire plant. Layouts and handling methods that have not been revisited despite significant product-mix or volume growth since they were designed are prime candidates, because the layout was optimized for conditions that no longer hold.
(b) Systematic procedure. The study follows the standard facilities-planning sequence, applied here as an improvement (not greenfield) study: define the study's objective and scope; collect current-state data (part (c)); analyze the existing flow, activity relationships, and handling methods against that data; generate alternative layout/handling improvements; evaluate each alternative against cost, flexibility, disruption-during-implementation, and the layout constraints already established; select the preferred alternative; plan phased implementation to minimize production disruption; and implement, then audit the realized results against the original objective, feeding findings into the next improvement cycle.
(c) Data/information required, and specific techniques. Required data: current layout drawings and space utilization; from-to material-flow volumes and frequencies between departments; material characteristics and unit-load practice; the existing handling-equipment inventory, condition and cost; production routings, schedules and volumes; labour and handling cost rates; and historical downtime, damage and safety-incident records. Specific techniques: from-to charts and flow-process charts to quantify and visualize current flow; activity-relationship (REL) charts for closeness needs not captured by flow volume alone; string diagrams or a walk-through to observe actual (versus documented) movement; time study/work sampling to quantify handling labour content; and, once alternatives are generated, computerized layout algorithms (CRAFT/CORELAP, Question 4) or simulation to evaluate and validate a proposed change before committing to physical implementation.
