Equipment Supervision Engineer cheat sheet

Stress = force/area (σ = F/A); strain = ΔL/L0; in the elastic region σ = E·ε, where E is Young's modulus and the slope of the stress–strain curve.

Yield strength marks the onset of plastic deformation (0.2% offset for materials without a distinct yield point); ultimate tensile strength is the maximum engineering stress before necking.

Hardness scales are empirical and non-interchangeable: approximate conversion only, e.g. HB ≈ 2·HV/2.5 relations hold loosely; use the standard conversion table for the specific material class.

Heat treatment decision rule: annealing softens and relieves stress; normalizing refines grain; quenching hardens; tempering restores toughness after quench - always temper after hardening.

Welded joint efficiency η reduces allowable stress: allowable = σ_allow × η; common values are 1.0 (full radiography), 0.85–0.9 (spot), 0.7 (no radiography) depending on the applicable code.

Surface roughness Ra is the arithmetic mean deviation of the profile; Rz is the maximum height of profile; a lower Ra requires finer machining and raises cost nonlinearly.

Tolerance stack-up: worst-case = Σ|t_i|; statistical (RSS) = √(Σt_i²); RSS assumes independent random deviations and yields a smaller, less conservative allowance.

Supervision is third-party control of quality, progress, and cost on behalf of the owner; the supervisor has no authority to alter the contract or the design without written owner approval.

Three control pillars:事前控制 (pre-event, preventive), 事中控制 (in-process, real-time), 事后控制 (post-event, verification); preventive control has the highest leverage and lowest rework cost.

The supervision plan (监理规划) is prepared by the chief supervision engineer and approved by the supervising entity's technical director before commencement.

The supervision implementation rules (监理实施细则) are prepared by the专业 supervision engineer for specialized, high-risk, or newly applied works, and approved by the chief supervision engineer.

Work hold points (停止点) require supervisor sign-off before the contractor may proceed; witness points (见证点) require notification but not mandatory presence.

Supervisor's core documents: supervision log (监理日记), monthly report, supervision notice (监理通知单), work suspension order (工程暂停令), and completion quality assessment report.

A work suspension order may be issued for serious quality hazards or unsafe conditions; it must be reported to the owner and the order lifted only after rectification is verified.

The supervision contract defines the scope, authority, fee, and liability; supervision authority exists only where the contract and applicable law grant it.

Registered equipment supervision engineers must practice within their registered scope and may not simultaneously serve as supervisor and as contractor's quality officer on the same project.

Conflicts of interest must be disclosed and avoided: no acceptance of gifts, gratuities, or subcontracting interests from contractors or suppliers on supervised projects.

Supervisor's signature on acceptance documents certifies that the work meets contract and code requirements; signing without verification creates personal and entity liability.

Mandatory standards (强制性条文) for equipment and pressure systems must be enforced regardless of contract silence; contract terms below the mandatory minimum are void.

Document retention: supervision records, inspection lots, and test reports must be archived for the period required by the applicable regulation and the contract.

Confidentiality: technical data, process parameters, and commercial terms learned during supervision may not be disclosed or reused without the owner's consent.

Design review gates: concept, preliminary, detailed, and manufacturing readiness; each gate requires documented closure of open items before the next phase.

Critical characteristics are identified by a risk-based method (e.g. FMEA severity × occurrence × detection); they drive inspection level and hold points.

Incoming material control: certificate of conformity plus, for critical items, independent re-test of chemical composition and mechanical properties.

Non-destructive testing method selection: RT for volumetric internal flaws, UT for internal planar flaws in thick sections, PT for surface-breaking flaws in non-porous materials, MT for surface/near-surface flaws in ferromagnetic materials.

Welder qualification and welding procedure qualification (WPS/PQR) must be verified before production welding; production welds must follow the qualified WPS.

First article inspection (FAI) verifies that the manufacturing process can produce a conforming part before mass production; results are recorded on the FAI report.

Nonconformity disposition categories: rework, repair (with design approval), use-as-is (with concession), reject/scrap; repairs affecting strength require design authority sign-off.

Bid evaluation methods: lowest evaluated price, and comprehensive scoring (technical + commercial); the method and weights must be fixed in the bidding documents before bid opening.

Bid validity period binds the bidder; the owner may request extension, and a bidder refusing extension may withdraw without forfeiting the bid bond.

Performance bond (履约保函) typically 5–10% of contract price; advance payment bond covers the prepayment and reduces as the prepayment is recovered.

Contract price forms: lump-sum (fixed price), unit-price (re-measured), and cost-plus; lump-sum transfers quantity risk to the supplier, unit-price leaves it with the owner.

Incoterms decide risk transfer and cost allocation: FOB risk passes at the ship's rail, CIF adds freight and insurance to the named destination, DDP places delivery duty at the buyer's site.

Variation orders require written instruction and agreed price/time adjustment before execution; unilateral contractor work without instruction is generally not compensable.

Claim time bars: notice of claim within the contractually specified period (commonly 28 days) after the event; late notice may extinguish the claim.

Installation prerequisites: foundation handover with elevation, centerline, anchor-bolt position, and concrete strength records verified against the equipment general arrangement drawing.

Alignment tolerances: shaft alignment checked for concentricity and parallelism (angular and offset); soft-foot check precedes final alignment and grouting.

Commissioning sequence: single-machine no-load test → single-machine load test → linked/interlocked no-load test → linked load test → performance test.

Pressure test pressure is commonly 1.25–1.5 times design pressure (per applicable code); hydrostatic test uses water and is followed by thorough drying before service.

Acceptance categories: concealed works acceptance, sub-item (检验批), sub-division (分项), division (分部), and unit works (单位工程) acceptance, in ascending order.

Performance acceptance requires measured capacity, efficiency, and consumption within guaranteed values; shortfall triggers liquidated damages or correction per contract.

Punch list (尾项清单) items must be closed and re-verified before final acceptance; outstanding items are tracked with responsible party and due date.

Critical path method: the critical path has zero total float; delaying any activity on it delays project completion by the same amount.

Total float = LS − ES = LF − EF; free float = ES of successor − EF of current activity; free float ≤ total float.

Earned value metrics: CV = EV − AC (positive = under budget); SV = EV − PV (positive = ahead of schedule).

Performance indices: CPI = EV/AC; SPI = EV/PV; values below 1.0 indicate cost overrun or schedule slippage respectively.

Estimate at completion: EAC = BAC/CPI when current cost performance is expected to persist; EAC = AC + (BAC − EV) when remaining work proceeds at budgeted rate.

Schedule compression: crashing adds resources to critical activities at extra cost; fast-tracking overlaps activities and raises risk; both must be justified by cost-benefit.

S-curve compares planned versus actual cumulative progress and cost; divergence in slope signals emerging deviation before it appears in periodic reports.

Risk = likelihood × severity; the risk matrix places items in unacceptable, tolerable (ALARP), and broadly acceptable zones.

Hierarchy of controls: elimination → substitution → engineering controls → administrative controls → PPE; PPE is the last line of defense.

FMEA: RPN = severity × occurrence × detection; high RPN items require corrective action, and RPN is recalculated after action to verify reduction.

Reliability metrics: MTBF = total operating time / number of failures; availability A = MTBF/(MTBF + MTTR); failure rate λ = 1/MTBF for constant-failure-rate (exponential) models.

Safety instrumented function integrity: SIL level determined by required risk reduction factor and verified by PFDavg calculation for the specified demand mode.

Hazardous area classification (gas: Zone 0/1/2; dust: Zone 20/21/22) determines the required equipment protection type and marking.

Incident investigation: preserve evidence, identify root cause (not just proximate cause), issue corrective actions with owners and deadlines, and verify effectiveness.

Case analysis structure: facts → applicable contract and code clauses → responsibility allocation → corrective action → prevention of recurrence.

When a defect is found after acceptance, trace the inspection record: missing hold-point sign-off or absent test data shifts liability toward the supervisor.

Delay analysis: determine whether the delay is owner-caused, contractor-caused, or excusable (force majeure); concurrent delay generally denies extension to both parties.

Quality accident classification typically by loss and consequence severity; the supervisor must report upward within the statutory time limit and preserve on-site evidence.

Change control case: an undocumented design change executed without written instruction is generally non-compensable and may be ordered removed.

Dispute resolution ladder: negotiation → mediation → adjudication/arbitration or litigation, as specified in the contract's dispute clause.

Lessons-learned output from a case must be specific and auditable: revised hold points, revised inspection plan, or revised supplier evaluation criteria.