Ptrotek | Industrial Services | Inspection Services

We have long experience in oil & gas industry ...

For more info, Contact Us

Our Articles

You can choos our articles from menu in below …

The Industrial Third Party Inspection Services article provides you with information about the services which are provided by third party inspection agencies.

These companies provide a variety of inspection services such as Pre-Shipment inspection, shop inspection, site inspection and Price Verification.

You may need to review this article in conjunction with the following articles to get a full understanding:

Industrial Inspection System

Third Party Inspection Agency

Third Party Independent Inspection

Third Party Quality Inspection

Third Party Inspection Services – Shop Inspection:

This is called Third Party Vendor Inspection or Third Party Shop Inspection. The purchaser is either the end-user or the engineering company under contract with an end-user. They may make a contract with a third party inspection company to do inspection work based on an agreed inspection and test plan.

For more information, please review the Inspection and Test Plan article.

Generally, the third party inspection company receives inspection notification, and carries out inspection and supplies the purchaser with an inspection report.

third party inspection services

Several inspection visits might be needed for each type of equipment depending on the equipment type and complexity.

The inspection company controls the project through inspection and test plan, and when all tasks are fulfilled by the manufacturer, they will issue an inspection release note and the manufacturer can organize for packing, marking and shipment.

For more information, please review the Shop Inspection article. This article provides you the links inside of this site for most of the oil and gas equipment third party inspection guidelines.

Third Party Inspection Services – Site Inspection:

Third party inspection companies are hired for site inspection for industrial projects. These companies are used for process and power piping, storage tanks, steel structures and pipeline inspection in their construction process.

Third Party Inspection Companies are not involved in the installation; the supervision normally is done by engineering company.

Contrary to shop inspection, the site inspection projects use the resident inspectors, which normally accommodated near the construction site.

Third Party Inspection Services – Pre-Shipment Inspection:

Pre-Shipment inspection has a commercial approach. Pre-Shipment inspection is mandatory in some countries.

When the buyer opens a Letter of Credit (LC) at the bank, and the funds are transferred through the buyer and seller banks, then a third party inspection agency might be necessary, and the name of this company will be stated on the LC, which is needed to certify the goods.

Without the third party inspection company certificate, funds will not be transferred between buyer’s and seller’s banks.

The scope of inspection for Pre-shipment inspection is visual quality, quantity, packing, marking and loading inspection.

There is clause in the LC as to the “conclusion,” which should be stated in the inspection certificate exactly.

For more detail on the Preshipment Inspection review following articles:

Pre-Shipment Inspection

Goods Inspection

Price Verification:

The price verification is mandatory in some countries. This service supports the customs authority to make sure the prices stated in declaration document are the real value agreed upon between buyers and sellers.

The service is sometimes required by banks to approve proforma invoices.

Some importers try to deceive customs by declaring the goods with a lower price so they pay less to import duties. A Third Party Inspection Company helps the customs authority to indicate the international price of the imported goods. This service is named third party inspection for customs.

Executive Summary & Industrial Inspection Scope

In demanding industrial environments across Oil, Gas, Petrochemical, Offshore, and Heavy Process Infrastructure, rigorous compliance with ISO 17020, API Source Inspector, ASME is essential to ensure operational integrity, personnel safety, and compliance with statutory regulatory frameworks. This technical specification provides QA/QC managers, procurement engineers, welding inspectors, and third-party inspection (TPI) agencies with an authoritative, field-tested guideline for “Industrial Third Party Inspection Services”.

Ensuring compliance regarding industrial third party inspection services services minimizes the risk of catastrophic asset failures, costly unscheduled shutdowns, and supplier non-conformances. The following technical sections delineate the scope of inspection, mandatory verification protocols, acceptance criteria, documentation deliverables, and root cause mitigation strategies.

Governing International Engineering Codes & Specifications

Verification and validation of Industrial Third Party Inspection Services must strictly conform to the latest editions of the following international engineering codes and project specifications:
• **Primary Standard Reference:** ISO 17020, API Source Inspector, ASME
• **Quality Management & Inspection Systems:** ISO 9001:2015 & ISO/IEC 17020 (Requirements for the operation of various types of bodies performing inspection)
• **Material Compliance & Traceability:** EN 10204 Type 3.1 / 3.2 Inspection Certificates for metallic and non-metallic pressure-retaining components
• **Personnel Qualification:** ASNT SNT-TC-1A / ISO 9712 for NDT personnel, CSWIP 3.1 / AWS CWI for welding inspection, and NACE / AMPP Level 2/3 for coating and corrosion personnel
• **Statutory & Health Safety Directives:** ASME Boiler & Pressure Vessel Code (BPVC), API Standards, OSHA, and regional local authority regulations.

Step-by-Step Quality Control & Inspection Procedure

The execution of quality surveillance for Industrial Third Party Inspection Services is structured across four progressive QA/QC intervention phases:

Stage 1: Pre-Inspection & Engineering Document Review (Review Point – R)

Prior to commencement of any physical activities or manufacturing operations related to Industrial Third Party Inspection Services, the contractor or vendor must submit all technical submittals to the Owner or TPI agency for formal review and approval.

  • Verification of approved Inspection and Test Plan (ITP) identifying all Hold (H), Witness (W), Review (R), and Surveillance (S) intervention points.
  • Cross-examination of Material Test Reports (MTR / Mill Certificates) against standard design specifications (ISO 17020, API Source Inspector, ASME).
  • Review and approval of specific Procedure Qualification Records (PQR), Welding Procedure Specifications (WPS), or calibration certificates.
  • Verification that all measurement instruments, gauges, and NDT equipment hold valid calibration certificates from ISO/IEC 17025 accredited calibration laboratories (within 6 to 12 months validity).

Stage 2: In-Process Witnessing & Fabrication Control (Witness / Hold Point – W/H)

During the active execution phase, the certified inspector performs physical surveillance to ensure strict adherence to certified drawings, manufacturing procedures, and code tolerances.

  • Verification of material traceability (heat number, heat treatment lot, plate number) transferred accurately onto fabricated components.
  • Dimensional verification and visual inspection using calibrated gauges, micrometer depth dials, or laser alignment systems.
  • Monitoring ambient environmental parameters (relative humidity, dew point, substrate temperature) when applying surface treatments, welding preheat, or pressure testing.
  • Witnessing non-destructive examination (RT, UT, MT, PT, PMI) at specified percentages according to project critical rating and code requirements.

Stage 3: Final Acceptance, Pressure/Performance Testing & Marking (Hold Point – H)

The culminating milestone where the fully assembled or completed item is subjected to definitive acceptance tests in the presence of the Owner’s Third-Party Inspector (TPI).

  • Execution of pressure proof tests (Hydrostatic at 1.3x to 1.5x MAWP or Pneumatic test) with dual calibrated pressure gauges and temperature recorders.
  • Full visual inspection of completed surfaces, welds, protective coatings, and flange contact faces for absence of mechanical damage or code defects.
  • Validation of permanent stamping, low-stress die markings, nameplate data verification, and barcoding in strict conformity with project specs.
  • Clearing all open punch-list items, non-conformance reports (NCRs), and concession requests prior to issuance of the release note.

Stage 4: Packing, Preservation & Inspection Release (Inspection Release Certificate – IRC)

Ensuring the inspected equipment is adequately protected against atmospheric corrosion, mechanical shock, and marine transit degradation.

  • Inspection of rust preventative coatings, desiccant bags, flange face blind protectors, and vapor corrosion inhibitor (VCI) packaging.
  • Verification of heavy-lift sea fastening lugs, center-of-gravity markings, and export crating compliance (ISPM 15 wooden crating).
  • Compilation and signing of the final Inspection Release Certificate (IRC / Shipping Release) and manufacturer data dossier (MDR).

Technical Acceptance Criteria & Tolerances Matrix

All measurements and physical characteristics must comply with the engineering tolerances and acceptance thresholds tabulated below:

Inspection Parameter / Test Item Applicable Standard & Clause Permissible Tolerance / Acceptance Limit Verification Method Intervention Type
Material Chemical & Mechanical Verification ISO 17020, API Source Inspector, ASME / EN 10204 3.1 100% compliance with minimum tensile, yield, elongation, and impact values (Charpy V-Notch at design temp) Optical Emission Spectrometry (OES) / MTR Verification Review (R)
Visual & Dimensional Tolerances ISO 17020, API Source Inspector, ASME / Project Specs Zero cracks, lack of fusion, severe pitting; dimensional tolerances within ±1.0mm to ±3.0mm per code drawings Calibrated Vernier, Bridge Cam, Depth Micrometer Witness (W)
Non-Destructive Examination (NDT) ASME Sec V / ASNT SNT-TC-1A 100% compliant with code acceptance criteria; zero planar defects or unpermitted volumetric indications Radiographic (RT) / Ultrasonic (UT) / Magnetic Particle (MT) Hold (H)
Pressure / Proof Testing (Hydrostatic) ISO 17020, API Source Inspector, ASME / ASME Sec VIII Test pressure maintained for minimum 30 to 60 mins; zero pressure drop, zero leakage or visible sweating Dual calibrated Bourdon pressure gauges + Chart Recorder Hold (H)
Surface Prep & Protective Coating Quality SSPC-SP / NACE / ISO 8501 Surface profile 50 – 75 µm; Dry Film Thickness (DFT) within 80/20 rule of specified nominal thickness Replica Tape (ASTM D4417) & Magnetic Gauge (SSPC-PA 2) Witness (W)
Nameplate & Final Preservation Verification API / ASME / Client Specs 316L SS nameplate securely affixed with correct design code, MAWP, design temp, and national board stamping Physical visual check & VCI preservation verification Hold (H)

Mandatory QA/QC Dossier & Inspection Deliverables

Prior to the final issuance of the Inspection Release Certificate (IRC), the contractor and vendor must compile and submit the verified manufacturer data record containing:

  • Approved Inspection & Test Plan (ITP) with sign-off stamps by Contractor, Client, and TPI.
  • Material Test Reports (MTR / Mill Test Certificates EN 10204 Type 3.1 or 3.2).
  • Certified Welding Procedure Specifications (WPS), Procedure Qualification Records (PQR), and Welder Performance Qualifications (WPQ).
  • Calibration Certificates for all test instruments and measuring equipment (NABL / ISO 17025 accredited).
  • Non-Destructive Examination Reports (RT, UT, MT, PT, PMI, Ferrite Content) evaluated by Level II/III inspectors.
  • Heat Treatment & PWHT Time-Temperature Recorder Charts with thermocouple layout drawings.
  • Hydrostatic / Pneumatic Pressure Proof Test Certificate with calibrated chart recorder logs.
  • Surface Preparation and Protective Coating Inspection Reports (Daily environmental log, blast profile, DFT summary).
  • Non-Conformance Report (NCR) and Concession Disposition Closeout Log.
  • Official Inspection Release Certificate (IRC / Shipping Release Note) permitting packing and dispatch.

Common Non-Conformances & Field Mitigation Strategies

Based on extensive third-party inspection field records in oil & gas projects, the following deviations require heightened surveillance:

Defect / Hazard: Material Grade Substitution & Lack of Heat Traceability

Root Cause: Uncontrolled workshop storage, missing color coding, or unverified supplier sub-tier procurement without EN 10204 3.1 documentation.

Preventative Action: Enforce strict 100% Positive Material Identification (PMI) prior to cutting, and mandatory material receiving inspection with physical stamping cross-referenced to original mill test certificates.

Defect / Hazard: Out-of-Tolerance Fit-Up & Alignment Mismatch

Root Cause: Poor thermal cutting, thermal distortion from excessive preheat, or inadequate jigging and tacking arrangements.

Preventative Action: Establish a mandatory Witness/Hold point at joint fit-up before root pass deposition. Use calibrated Hi-Lo gauges to verify bevel angle, root face, and root gap according to the qualified WPS.

Defect / Hazard: Premature Coating Delamination & Blistering Under Film

Root Cause: Excessive soluble salt contamination (>20 mg/m²) left on the substrate, blast cleaning below dew point (<3°C above dew point), or oil/moisture in the blasting compressor air line.

Preventative Action: Perform Blotter Test (ASTM D4285) daily on compressed air, enforce Bresle patch chloride testing, and apply primer within 4 hours of abrasive blasting before rust blooming initiates.

Defect / Hazard: Pressure Drop During Final Hydrostatic Proof Testing

Root Cause: Micro-leakage through temporary test flange gaskets, entrapped air pockets inside vessel high points, or inadequate temperature stabilization.

Preventative Action: Ensure thorough venting at all high-point vents until bubble-free fluid emerges, allow minimum 15-minute temperature stabilization between filling medium and ambient metal, and torque all blind flanges with calibrated torque wrenches.

Frequently Asked Questions (FAQ)

Q: What are the mandatory qualifications for inspectors verifying Industrial Third Party Inspection Services?

A: Inspectors must hold recognized international certifications applicable to the discipline. For welding and fabrication: CSWIP 3.1/3.2, AWS CWI, or API 510/570 Source Inspector. For NDT: ISO 9712 or ASNT SNT-TC-1A Level II minimum. For coatings: NACE / AMPP Level 2 or FROSIO Level III. Additionally, the inspection agency must operate under an ISO/IEC 17020 accredited quality management system.

Q: How does PtroTek resolve non-conformances (NCRs) encountered during vendor surveillance?

A: When a deviation from certified drawings or ISO 17020, API Source Inspector, ASME is detected, the inspector issues a formal Non-Conformance Report (NCR) within 24 hours. The vendor must submit a Root Cause Analysis (RCA) and proposed disposition (Rework, Repair, or Concession). Work on the affected component is halted (Hold Point) until the Owner’s engineering authority approves the disposition and a re-inspection confirms full compliance.

Q: What is the difference between Witness (W) and Hold (H) points in an Inspection & Test Plan (ITP)?

A: A Hold Point (H) is a mandatory milestone where fabrication or testing CANNOT proceed without the physical presence of the designated client or third-party inspector. Written clearance or stamping is strictly required. A Witness Point (W) requires prior notification (typically 24 to 48 hours) to the inspector; however, if the inspector fails to attend at the scheduled time, fabrication or testing may proceed with subsequent review of the test records.

Q: Can international clients review inspection reports and photos in real time?

A: Yes. PtroTek provides comprehensive Flash Reports issued within 24 hours of inspection completion, followed by detailed formal inspection reports accompanied by high-resolution calibrated photographic evidence, dimension logs, and signed vendor test records for complete global transparency.

Need Certified Third-Party Inspection (TPI) Support?

PtroTek provides international vendor surveillance, ASME code vessel inspection, welding QA/QC, and protective coating verification across Southeast Asia, the Middle East, and global fabrication hubs.

Request a Technical Inspection Quote