エンジニアリング英語：必須語彙とフレーズ

"tensile strength"

The maximum stress a material can withstand while being stretched before it breaks

"The design team specified a steel alloy with a tensile strength of 550 MPa to handle the bridge load."

"thermal conductivity"

A measure of a material's ability to transfer heat through itself

"Copper's high thermal conductivity makes it the preferred choice for heat exchanger tubes."

"fatigue failure"

The fracture of a material caused by repeated cyclic loading below its ultimate tensile strength

"Inspection revealed fatigue failure in the crankshaft caused by millions of stress cycles over five years."

"redundancy"

The inclusion of extra components or systems that can take over if a primary component fails

"The control system was designed with triple redundancy to ensure safe operation even if two channels failed."

"stress concentration"

A localised increase in stress around a geometric feature such as a hole, notch, or corner

"The sharp notch at the base of the bracket created a stress concentration that initiated the crack."

"yield point"

The stress level at which a material begins to deform plastically and no longer returns to its original shape

"The component was loaded beyond its yield point during the test, leaving a permanent bend in the beam."

"coefficient of thermal expansion"

A material property describing how much it expands or contracts per degree of temperature change

"Engineers accounted for the coefficient of thermal expansion when designing the expansion joints in the pipeline."

"resonant frequency"

The natural frequency at which a structure vibrates most intensely when excited by an external force

"The bridge deck collapsed because wind-induced oscillations matched its resonant frequency."

"finite element analysis"

A computational method that divides a structure into small elements to simulate how it behaves under loads

"The team ran finite element analysis on the chassis to identify stress hotspots before building a prototype."

"tolerance stack-up"

The cumulative effect of individual dimensional tolerances on the overall fit or function of an assembly

"A tolerance stack-up analysis confirmed that the parts would assemble correctly even at worst-case dimensions."

"design of experiments"

A systematic method for planning tests to understand how input variables affect an output

"They used design of experiments to identify which combination of temperature, pressure, and feed rate maximised yield."

"factor of safety"

The ratio of a structure's capacity to the maximum load it is expected to carry, providing a margin against failure

"The code required a factor of safety of 3.0 for the lifting hook, meaning it could hold three times the rated load."

"iterative design"

A development process in which successive versions are built, tested, and refined based on results

"Using iterative design, the team improved the heat sink geometry through five prototyping cycles."

"computational fluid dynamics"

A simulation technique that models fluid flow, heat transfer, and chemical reactions to predict system behaviour

"Computational fluid dynamics revealed that the original valve geometry caused excessive pressure drop at full flow."

"proof of concept"

An early demonstration that a design idea is feasible before full development resources are committed

"The proof of concept showed the sensor array could detect microcracks, securing funding for the full prototype."

"design margin"

The additional capability or capacity built into a design beyond the minimum required by specification

"A 15 % design margin on the motor rating ensured reliable operation under unexpected peak loads."

"scope of work"

A document that defines exactly what tasks, deliverables, and boundaries are included in a project

"Before signing the contract, both parties agreed on a detailed scope of work to avoid misunderstandings later."

"technical specification"

A formal document stating the requirements, materials, tolerances, and standards a product or system must meet

"The client issued a technical specification requiring all welds to conform to AWS D1.1 structural welding code."

"change request"

A formal proposal to modify the original design, schedule, or cost of an engineering project

"The customer submitted a change request to increase the pipe diameter, adding two weeks to the schedule."

"milestone"

A key event or stage in a project schedule that marks the completion of a significant phase of work

"The critical design review was set as the milestone that had to be passed before manufacturing could begin."

"as-built drawing"

A revised set of engineering drawings that records how a structure was actually constructed, including any site changes

"Facilities management requested as-built drawings to ensure accurate records for future maintenance work."

"punch list"

A document listing outstanding tasks, defects, or incomplete items that must be corrected before project handover

"The commissioning engineer produced a punch list of twelve items requiring attention before final acceptance."

"request for proposal"

A formal invitation for suppliers or contractors to submit bids for a defined engineering scope of work

"The company issued a request for proposal to six structural engineering firms for the new warehouse design."

"lessons learned"

A documented record of what went well and what could be improved, captured at the end of a project

"The lessons learned report highlighted that earlier supplier engagement would have reduced material lead times."

"nondestructive testing"

Inspection methods that evaluate a component's integrity without damaging or altering it

"Nondestructive testing using ultrasonic probes detected a subsurface crack in the turbine blade."

"statistical process control"

A method of using statistical tools to monitor and control a manufacturing process and reduce variation

"Control charts from statistical process control showed the injection moulding machine was drifting out of tolerance."

"root cause analysis"

A systematic investigation to identify the fundamental reason why a failure or defect occurred

"Root cause analysis traced the casting defects back to inconsistent pouring temperature in the foundry."

"first article inspection"

A comprehensive review of the first part produced to verify it meets all drawing and specification requirements

"The first article inspection confirmed the machined housing met all dimensional requirements before batch production."

"corrective action"

A documented step taken to eliminate the cause of a defect or non-conformance and prevent its recurrence

"The corrective action plan required retraining operators and adding a go/no-go gauge to the inspection process."

"surface finish"

A measure of the texture and roughness of a machined surface, usually expressed as Ra in micrometres

"The bearing seat required a surface finish of Ra 0.8 µm to ensure proper fit with the inner race."

"geometric dimensioning and tolerancing"

A symbolic language on engineering drawings that defines the allowable variation in form, orientation, and location of features

"Geometric dimensioning and tolerancing ensured the datum reference frame was defined unambiguously on the drawing."

"capability index"

A statistical measure of how well a manufacturing process is able to produce parts within specification limits

"A capability index of 1.67 confirmed the grinding process was well within the required diameter tolerance."

"failure mode and effects analysis"

A systematic method for identifying potential failure modes, their causes, and their impact on system function

"Failure mode and effects analysis on the braking system identified a single-point failure in the hydraulic line."

"risk assessment"

A process of identifying, evaluating, and prioritising hazards to determine appropriate control measures

"The risk assessment rated the high-pressure vessel as a critical item requiring a third-party safety inspection."

"hazard and operability study"

A structured technique used in process engineering to identify potential hazards and operational problems in a system

"The hazard and operability study flagged reverse flow as a credible scenario requiring a non-return valve."

"permit to work"

A formal authorisation document required before carrying out high-risk maintenance or construction activities

"No work could begin in the confined space until a valid permit to work had been issued by the safety officer."

"design life"

The intended service period for which an engineering structure or component is designed to perform reliably

"The offshore platform had a design life of 25 years, after which a full structural reassessment would be required."

"proof test"

A test that applies a load or pressure above normal operating levels to verify structural integrity without causing damage

"Every pressure vessel was subjected to a proof test at 1.5 times working pressure before leaving the factory."

"CE marking"

A mandatory declaration that a product meets European Union safety, health, and environmental requirements

"The machinery directive required CE marking before the automated press could be sold in the European market."

"lock-out tag-out"

A safety procedure that ensures hazardous energy sources are isolated and secured before maintenance work begins

"Strict lock-out tag-out procedures prevented accidental energisation of the conveyor while technicians replaced the drive belt."

"in accordance with"

A phrase indicating that work was performed following a specific standard, code, or specification

"All welds were inspected in accordance with ISO 9606 qualification requirements for welding procedures."

"it is recommended that"

A cautious phrase used in technical reports to propose a course of action without mandating it

"The inspection report stated: "It is recommended that the corroded section be replaced within the next 12 months.""

"design intent"

The underlying purpose or performance goal that a component or system is meant to achieve

"The revision preserved the original design intent while reducing manufacturing cost by 18 percent."

"to flag up"

To draw attention to a potential problem, risk, or issue for further discussion

"The site engineer flagged up a discrepancy between the drawing dimensions and the actual installed pipe route."

"sign off"

To formally approve a document, design, or completed piece of work, accepting responsibility for it

"The chief engineer was required to sign off all calculations before they were submitted to the client."

"walk through"

To explain or review something step by step with colleagues or stakeholders

"The project manager walked through the updated risk register at the start of the weekly team meeting."

"back-of-envelope calculation"

A quick, approximate estimate done to check whether an idea is feasible before detailed analysis

"A back-of-envelope calculation showed the proposed motor was far too small for the required torque."

"redline"

Handwritten or marked corrections made directly on a drawing or document to indicate required changes

"The client returned the drawing with redline comments requesting a larger access hatch on the side panel."