JIS Consultancy Limited
Engineered.
Analysed.
Certified.

Nearly 30 years of specialist expertise across nuclear, oil & gas, pharmaceutical, power generation and energy. Rigorous, code-compliant engineering delivered to ASME, EN, PED and API standards.

Engineering Design
Compliance and shell verification.
Technical Analysis
Forensic reporting and EDX support.
Regulatory Control
Engineering change control workflows.
30+
Years Experience
300+
Vessels to PED
6+
Sectors Served
20+
Codes & Standards
About JIS Consultancy

Jonathan Saa — Principal Consultant

JIS Consultancy Limited is a specialist engineering practice led solely by Jonathan Saa — a Senior Engineering Consultant with 30+ years of post-graduate experience delivering compliance-led solutions across nuclear, oil & gas, pharmaceutical, power generation and energy sectors.

Jonathan has held roles as Responsible Engineer, Technical Authority and Lead Consultant on major UK programmes, applying codes including ASME, EN 13445, PED, ATEX and API. His project work spans eight countries, combining computational rigour with practical engineering judgement at every stage.

Types of Organisations Worked With
🏭
Major EPC Contractors
Large engineering, procurement & construction firms delivering complex industrial programmes
⚛️
Nuclear Operators & Decommissioners
Licensed nuclear site operators, decommissioning authorities and NDA supply chain
💊
Pharmaceutical Manufacturers
Global pharma companies requiring GMP-compliant vessel design and pressure system validation
🛢️
Oil, Gas & Petrochemical
Upstream, midstream and downstream operators across the UK, Europe and Africa
Power Generation & Utilities
Conventional and renewable power plant operators, grid infrastructure and energy utilities
🔬
Specialist OEMs & Fabricators
Pressure vessel and heat exchanger manufacturers requiring third-party technical authority sign-off
“Every calculation, analysis, and design decision must be defensible — not just functional.”
30+
Years Post-Graduate Experience
8
Countries Delivered In
Sectors
Nuclear Oil & Gas Pharmaceutical Power Generation Energy
Codes & Standards
ASME EN 13445 PED ATEX API Machinery Directive PD 5500
Roles Held
Responsible Engineer  ·  Technical Authority  ·  Lead Consultant  ·  Work Package Owner
Explore Further
Consultancy Services

What JIS Consultancy Delivers

Learn More — Expertise

JIS Consultancy Limited offers specialist engineering consultancy across six core disciplines, backed by three decades of cross-sector experience and deep knowledge of international codes and standards.

H PV-001 EN 13445 : ASME VIII DIV.1
⚙️
01

Pressure Vessel Design & Analysis

Design, analysis and compliance assessment of pressure-retaining equipment. API 579 fitness-for-service, Design-by-Analysis, data sheets and technical file compilation.

ASME VIIIEN 13445PD 5500API 579API 650
Fy Fx ΔT ASME B31.3 CAESAR II STRESS ISOMETRIC
〰️
02

Pipework Stress Analysis

Static and dynamic analysis using Caesar II and AutoPipe. Full load cases including seismic, blast, wind, surge and thermal expansion across all major piping codes.

ASME B31.3ASME B31.8EN 13480Caesar IIAutoPipe
346 MPa 0 MPa σeq FEA VON MISES ANSYS MECHANICAL ASME DBA
🔬
03

Finite Element Analysis

Structural, thermal and vibration FEA for pressure equipment and specialist components. Nonlinear, fatigue, local load and lifting analysis using Ansys and Staad Pro.

AnsysStaad ProASME DBAFatigueVibration
TECH FILE CE CE PED 97/23/EC ISO 9001 : 2015 UK PER COMPLIANT ATEX DIRECTIVE REGULATORY COMPLIANCE TECHNICAL FILE CE MARKING
📋
04

Regulatory Compliance

Full lifecycle PED/PER compliance from material appraisal through to technical file approval, CE marking, supplier audit and ISO 9001 implementation.

PED 97/23/ECPER (UK)ATEXISO 9001CE Marking
GMP T=121°C PHARMA REACTOR EN 13445 GMP FAT / SAT
🧪
05

Pharmaceutical Engineering

Tank and vessel design to EN 13445 for GMP facilities. FAT/SAT supervision, surface anomaly investigation and Work Package Owner accountability.

EN 13445FAT/SATGMPAPI 579
P1 P2 ΔP CFD VELOCITY PROFILE FLUENT TWO-PHASE FLOW
💨
06

CFD & Flow Analysis

Computational fluid dynamics for internal and external flow, two-phase analysis, window burst behaviour and thermal modelling using Fluent and FLO EFD.

Fluent CFDFLO EFDTwo-PhaseThermal
Manufacturing Excellence

Vessel Manufacturing & Quality Management

Under Jonathan Saa's technical leadership, JIS Consultancy has delivered over 300 pressure vessels to full PED compliance, spanning pharmaceutical, chemical, oil & gas and power generation — from design appraisal through to CE marking.

300+
Vessels to PED
EN 13445
Primary Code
FAT/SAT
Supervised & Signed Off
CE
Marked & Compliant
Zero
Compliance Failures
Case Study — Manufacturing Non-Conformance

Black Residue Contamination: Root Cause Investigation & Resolution

During manufacture of stainless steel vessels to EN 13445 for a pharmaceutical facility, black residue contamination was identified at FAT. Jonathan led the root cause investigation and structured a multi-stage remediation programme that resolved all non-conformances without programme delay.

Root Cause

Embedded iron particles and surface oxides from grinding operations. Inadequate carbon steel tooling segregation introduced free iron into the stainless substrate, promoting black oxide formation and corrosion risk.

Compliance Risk

Contamination compromised corrosion resistance, violated GMP surface finish requirements and invalidated PED technical file acceptance. Vessels could not be released until EN 13445 and PER compliance was demonstrated.

Programme Outcome

All vessels remediated on schedule. Updated manufacturing controls and ITP hold points embedded into the supplier quality plan, preventing recurrence across the full programme.

Five-Stage Resolution Process

1
Mechanical Preparation

Affected areas reworked using dedicated stainless steel grinding discs and flap wheels, fully segregated from carbon steel tooling. Surface profiles verified to EN 13445 and client specification.

2
Chemical Passivation

Citric acid passivation applied to ASTM A967 / BS EN ISO 16048, restoring the passive chromium oxide layer and eliminating free iron. Verified by ferroxyl testing and surface inspection.

3
Hygiene Protocol Implementation

Full workshop hygiene audit, dedicated tooling registers, formalised cleaning procedures and area zoning enforced to prevent cross-contamination between carbon and stainless steel work.

4
Electrochemical Compliance (ECC) Verification

Electrochemical corrosion testing deployed to confirm passive layer integrity. Results documented as objective evidence within the PED technical file and FAT inspection records.

5
ITP Hold Point & Sign-Off

Formal hold point inserted at post-passivation stage for all subsequent vessels. Jonathan provided technical sign-off, closing the NCR and releasing vessels for hydrostatic test and CE marking.

Passivation & Surface Treatment

Citric and nitric acid passivation to ASTM A967, post-weld treatment and surface finish verification for pharmaceutical and hygienic-grade vessels.

Workshop Hygiene Management

Tooling segregation, dedicated SS work zones, cleaning protocol authorship and supplier audit against GMP and EN 13445 requirements.

ECC & Ferroxyl Testing

Electrochemical corrosion compliance testing and ferroxyl inspection as objective evidence of passive layer integrity within PED technical files.

Non-Conformance Management

Root cause analysis, corrective action planning, ITP hold point integration and formal NCR closure within ISO 9001 and PED quality frameworks.

FAT / SAT Supervision

Witness and sign-off of Factory and Site Acceptance Testing including dimensional, hydrostatic and surface inspection across large vessel programmes.

PED Technical File Compilation

End-to-end technical file management including design calculations, material traceability, weld records, NDE, hydrostatic test certificates and CE Declaration of Conformity.

Technical Capability

Technical Expertise

A comprehensive technical toolkit built over three decades of high-stakes engineering. Select a category to explore, or search within any area.

30+
Years Experience
18
Codes & Standards
9
Industry Sectors
12
Software Platforms
Codes & Standards
Design, analysis and fabrication codes applied across pressure equipment, structural and piping work. Click any code to see its application area.
ASME VIII ASME B31.3 ASME B31.8 ASME B31.1 ASME III NC ASME DBA EN 13445 EN 13480 EN 14015 PD 5500 EN 12952 R3 EN13840 API 650 API 579 AISC ASD Eurocode DNV Norsok
No codes match your search.
18 codes & standards
Software Tools
Industry-standard engineering analysis platforms used across FEA, pipework stress, CFD and draughting disciplines.
Ansys FEA Caesar II AutoPipe Staad Pro Etabs Fluent CFD FLO EFD AutoCAD Inventor CADWorx MathCAD Visual Basic
No tools match your search.
12 software platforms
Regulatory Frameworks
Directives, regulations and compliance frameworks governing pressure equipment, hazardous areas, machinery and quality systems.
PED 97/23/EC UK PER ATEX Directive Machinery Directive ISO 9001:2015 ISO 9001 Lead Auditor CDM Regulations CE Marking Module Conformances Technical File Compilation
No frameworks match your search.
10 regulatory frameworks
Industry Sectors
Sectors served across a 30-year consultancy career, spanning the most safety-critical and highly regulated industries globally.
⚛ Nuclear
Sizewell B, Hunterston B, Torness — ASME III, R3, seismic & missile analysis
⛽ Oil & Gas
Shetland Gas Plant, Grangemouth — B31.3/B31.8, PED, DNV offshore
💊 Pharmaceutical
Novo Nordisk, AstraZeneca — EN 13445, EN 13480, FAT/SAT supervision
⚡ Power Generation
Eraring, Ratcliffe — SCR plant design, PED CE approval, pressurised components
🏭 Petrochemical
SASOL, Grangemouth — API 650/579, EN 14015 storage tanks, PED compliance
🔬 R&D / Research
STFC Oxford, Leeds Uni — ASME DBA, vacuum chambers, FEA vibration, CFD
🌿 Environmental
Air filtration, Gas Suspension Absorbers, Ceramic & Fabric Filters
⚓ Marine Offshore
DNV, Norsok structural marine offshore review for North Sea projects
⚙ Energy & CHP
Combined Heat and Power plant design and pressure system engineering
Analysis Specialisms
Advanced analytical techniques applied to pressure equipment, pipework and structures across safety-critical and high-consequence environments.
Static Stress Seismic Analysis Fatigue Analysis Vibration Analysis Thermal Analysis Blast Loading Wind Loading Local Load Assessment Surge / Water Hammer Nozzle Analysis Missile Impact Two-Phase CFD
No specialisms match your search.
12 analysis specialisms
Engineering Management
Senior delivery and governance roles spanning technical authority, project ownership, supplier oversight, and quality management system leadership.
Work Package Owner Technical Authority Responsible Engineer FAT/SAT Supervision Supplier Audit Inspection Plan Dev. Equipment Specification Team Leadership ISO 9001 Lead Auditor
No capabilities match your search.
9 management capabilities
FEA Work — Stress Analysis Examples
Representative finite element stress analysis outputs produced for pressure vessel and pipework systems. Von Mises stress contours, mesh detail and loading annotations as delivered in engineering reports.
FEA Stress Analysis – Complex Process Manifold Cross-Section
Process Manifold — FEA Stress Analysis (Cross-Section)

Combined pressure + weight load case on a multi-branch manifold at 20.0 MPa internal pressure. Solid hexahedral mesh highlights stress concentration at branch-header welds, elbow/valve body peaks and stress gradient through the manifold wall. Bolt pre-load simulation at blind flange termination included.

Von Mises Stress 20.0 MPa Ansys FEA Solid Hex Mesh ASME VIII
FEA Stress Analysis – Longitudinal Section View
Pressure Vessel — Longitudinal Section FEA

Pressure vessel under 15.0 MPa internal load — longitudinal cut plane reveals stress gradient through head thickness and high stress concentration at the nozzle junction. Solid finite element mesh with fixed support boundary conditions applied at saddle locations.

Von Mises Stress 15.0 MPa Ansys FEA Nozzle Analysis EN 13445

Representative outputs only. Actual deliverables are provided under formal engineering sign-off and covered by professional indemnity insurance.

Structure & Governance

Organisation

JIS Consultancy operates as a lean, specialist engineering practice — structured for agility, accountability, and direct senior-engineer engagement on every project.

Practice Structure

Principal Engineer
Jonathan I. Saa
30+ years experience
Sole technical authority & client point of contact on all engagements.
Operating Model
  • Independent practice — no sub-contracting of technical work
  • Direct senior-engineer delivery on every project
  • Available for UK, EU and international engagements
  • On-site, hybrid or fully remote working
  • Day rate, fixed-fee and retainer arrangements available
Quality & Compliance
  • ISO 9001 Lead Auditor certified
  • Full professional indemnity insurance
  • Deliverables issued under formal engineering sign-off
  • Confidentiality agreements standard on all projects

Sectors Served

⚛️
Nuclear Power
🛢️
Oil & Gas
💊
Pharmaceutical
Power Generation
🏭
Petrochemical
Marine Offshore

Why Clients Choose JIS

🎯
Senior-only delivery
Every calculation, report and review is performed by a chartered engineer with decades of relevant experience — never delegated to juniors.
Rapid mobilisation
No procurement process, no onboarding delays. Technical work begins within days of engagement.
🌍
International experience
Projects delivered across UK, Europe, Middle East and South America under multiple regulatory frameworks.
Track Record

Client Portfolio

A 30-year record of delivery for globally recognised organisations across nuclear, oil & gas, pharmaceutical, power generation and petrochemical sectors.

Novo Nordisk
Pharmaceutical

FEA for pressure-retaining components, EN 13445 vessel design, API 579 fitness-for-purpose, FAT supervision and PER compliance across pharmaceutical plant upgrade.

BakerHicks (BakerHughes)
Pharmaceutical

Function Owner for Novo Nordisk plant upgrade — FEA, EN 13480 pipework review, pressure vessel data sheets and equipment specifications.

Sizewell B Nuclear Power Station
Nuclear

Responsible Engineer — ASME III, R3 EN13840, B31.1. Missile impact, surge, seismic and wind calculations; structural steelwork to AISC ASD.

STFC Oxford
Research

Vacuum chamber design to ASME VIII Div 2 (DBA), vibration analysis via Ansys FEA, and CFD analysis of window burst behaviour.

GDF / Petrofac — Shetland Gas Plant
Oil & Gas

Final technical authorised signatory. Caesar II / AutoPipe to ASME B31.3/B31.8 with PED 97/23/EC; structural marine offshore review to DNV.

Eraring Power Station
Power Generation

On-site technical authority. Pressurised economiser design with full CE approval to PED 97/23/EC.

Grangemouth Refinery
Petrochemical

Technical Authority for API 650 and EN 14015 storage tanks.

Hunterston B Nuclear Power Station
Nuclear

ASME III NC and B31.1 seismic analysis for nuclear plant systems.

Ratcliffe Power Station
Power Generation

Lead Engineer for first-of-kind UK SCR plant design and delivery.

Torness Nuclear Power Station
Nuclear

EN 13480 and EN 13445 analysis for nuclear plant systems.

SASOL Petrochemical
Petrochemical

Analytical engineering and PED 97/23/EC compliance for petrochemical plant equipment.

University of Leeds
Research

ASME/TEMA Shell & Tube Heat Exchanger design and technical file approval via Lloyds Register.

AstraZeneca
Pharmaceutical

Pharmaceutical Glove Box design and specialist pressure vessel engineering to pharmaceutical standards.

Tyco — AG Marvac & Whessoe Vapour
Industrial

PED 97/23/EC implementation and type examination. New product development: API Tanks, Detonation Flame Arrestors and Safety Relief Valves.

SECTORS: Nuclear Oil & Gas Pharmaceutical Power Generation Petrochemical Research Industrial
Engineering Tools

Calculators

Interactive engineering calculators built on the same codes and standards used in JIS Consultancy project work.

Directive 2014/68/EU — Annex II
PED Hazard Category Calculator
Determine pressure equipment classification per Annex II Tables 1–9

Disclaimer: Results are consistent with PED 2014/68/EU Annex II classification rules and are provided for preliminary guidance only. They do not replace formal engineering review or Notified Body assessment. Equipment meeting Article 4(3) must be designed to sound engineering practice (SEP) but must not bear the CE marking.

EN 13445-3 — Cl. 11 Strength & Rigidity · Bisection MAWP Solver
Flange Design — Integral Welding Neck Type
Flange Geometry
mm
mm
mm
mm
mm
mm
mm
Bolting
mm²
MPa
Design
MPa
MPa
MPa
Gasket
mm
mm
MPa
Load Case
Geometric Factors (Interpolated)
Factor Y
Factor Z
Factor K
Factor T
g₀/e_f
d/D (k)
Moments (Cl. 11.5)
Wm1 min bolt load (operating)
Wm2 min bolt load (seating)
W actual bolt load
M0 total flange moment
Stress Checks (Cl. 11.6)
σR radial
σT tangential
σH hub longitudinal
Allowable (f)
Rigidity Check (Cl. 11.7 — J ≤ 1.0)
Rigidity Factor J
Governing limit
Utilisation at Design P
Radial stress σR/f
Tangential σT/f
Hub σH/f
Rigidity J
MAWP (Bisection Solver)
— MPa
Design P:
Flange Cross-Section — Forces & Moment Arms
+ 2bGπmP;   Wm2 = bGπy;   M0 = W·hD+FG·hG+FT·hT;   σR = Y·M0/ef²;   σT = Z·M0/ef² − Z·σR/Y;   J = 52.14M0/(E·ef³·V) ≤ 1.0. Factors Y, Z, K, T interpolated from Cl. 11 Table A.1 via g₀/e_f and K = A/B ratios.

Integral welding-neck flange (Type 1). Gasket contact width b = (Go−Gi)/4. Y/Z/K/T factors derived from the Taylor Forge / EN 13445-3 Annex A polynomial curves as a function of k = A/B and h₀/√(B·g₀). MAWP found by 25-iteration bisection between 0 and 100 MPa satisfying both stress (σ ≤ f) and rigidity (J ≤ 1.0).
EN 13445-3 / General Principles — Skirt-Supported Vertical Vessels
Base Ring Design — Bearing Pressure & Thickness
Applied Loads
kN
kN·m
Ring & Skirt Geometry
mm
mm
mm
mm
mm
Allowable Stresses
MPa
MPa
Ring Section Properties
Ring Area A
Section Modulus Z
Outer cantilever lo
Inner cantilever li
Controlling length l
Bearing Pressures
Compressive pcomp = W/A
Bending pbend = M/Z
Max bearing pmax
Min bearing pmin
Concrete Bearing Check (pmax ≤ fc)
pmax
Allowable fc
Ring Thickness Check — treq = l·√(3pmax/f)
Required treq
Provided tr
Overall Result
Section Schematic — proportional to input dimensions
Plan View (Top)
Cross-Section A–A

A = π/4·(Do²−Di²);   Z = π/(32·Do)·(Do⁴−Di⁴);   pcomp = W/A;   pbend = M/Z;   pmax = pcomp+pbend;   l = max(lo, li);   treq = l·√(3pmax/f). All forces in N, dimensions in mm, pressures in MPa.

Uplift (pmin < 0) indicates tension under the ring — anchor bolts must be sized for the net uplift force. For stiffened base rings with gussets, the cantilever length l should be taken to the nearest stiffener rather than the skirt wall.
EN 13445-3 — Cl. 8 · Elastic Instability & Yield
Cylindrical Shell — External Pressure
Unstiffened & Ring-Stiffened shells · Elastic buckling, yield & interaction collapse pressure
Shell Geometry
mm
mm
mm
Distance between heads or bulkheads
Material Properties
MPa
MPa
Section Schematic
Cross-Section
Elevation View
CALC REF: JIS-EXT-001  |  CODE: EN 13445-3 Cl. 8
DESIGN BASIS: External pressure, cylindrical shell — buckling & yield assessment
Governing Equations
Yield Pressure Py = σe · ea / R
Elastic Instability (min over n≥2) Pm = (E/R) · [shell membrane + shell bending + stiffener terms]
Interaction Collapse Pr = Py·Pm / √(Py² + Pm²)
Assumptions & Scope
Buckling modes: Lobes n = 2…50 iterated; critical (minimum Pm) governs.
Safety factor: γ = 1.5 applied to Pr to give allowable Pall.
Stiffened case: Local analysis (spacing Ls) and global (full length L + Ie) both assessed — lesser governs.
Limitation: Simplified continuous interaction formula used for preliminary assessment. Full EN 13445-3 Cl. 8 requires graphical or polynomial root solution for exact compliance.
Derived Geometry
Mean Radius
R = (Do − ea) / 2
mm
Cylinder Parameter
Z = π·R / L
Shell Analysis (Unstiffened)
Yield Pressure
Py = σe·ea/R
MPa
Elastic Instability
Pm (min, n lobes)
MPa
Critical lobe count
Interaction Collapse
Pr,local
MPa
Result
Allowable External Pressure
MPa
Pall = Pr / 1.5
AWAITING INPUT
Enter all inputs to compute
Interaction formula: Pr = Py·Pm / √(Py² + Pm²) gives a continuous lower-bound approximation. EN 13445-3 Cl. 8.5 specifies the exact knock-down method using polynomial roots from Fig. 8.5-1; for code-compliance use the standard graphical procedure.

Disclaimer: Results are for preliminary guidance only and do not replace formal engineering review or code-qualified calculations. Design stress f must be taken from EN 13445-3 Annex B material tables at design temperature.

Enquiries

Engage JIS Consultancy

All work is delivered personally by Jonathan Saa — you engage directly with the consultant.

Location
Sutton Coldfield, West Midlands, UK

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Organisations & Industry Experience
Novo
Nordisk
Pharmaceutical
BakerHughes
Energy Services
Doosan
Babcock · Power
Power Generation
Bureau
Veritas
Inspection & Testing
AstraZeneca
Pharmaceutical
Tyco
Industrial
Engie
Energy
Doosan
Babcock
Nuclear & Power
Influit
Engineering
Oil & Gas
STFC
Oxford
Research & Science
Petrofac
Oil & Gas EPC
Ineos
Chlor
Chemical
Eraring
Power Station
Power Generation
Powder Systems
Limited
Pharmaceutical
Scottish
Power
Power Generation
Prospect
Services
Engineering
EDF Energy
Sizewell B
Nuclear
GDF Suez
Sullom Voe
Oil & Gas
Shell UK
Oil & Gas
Statoil
Petroleum
Oil & Gas