Process and mechanical · SERNEM

Flange Assembly and Controlled Bolt-Up Method Statement

Tightening bolts alone does not prove a leak-tight joint. Component selection, flange faces and tightening procedures must follow approved engineering documentation.

Illustrative work method — not a permitVerify site permits, risk assessments, approved procedures, competent engineering, equipment instructions and local laws separately. This page does not define test pressures, torque values, anchor ratings or work authorization.

Work sequence, hazards and safeguards

Illustrative sequence only: adapt to the approved job pack and site conditions.

  1. 1

    Identify joint and specification

    Hazard
    Wrong flange class, gasket or material
    Safeguard
    Match approved isometric, material records and gasket/fastener requirements.
  2. 2

    Verify isolation and boundaries

    Hazard
    Pressure, residual product or wrong equipment
    Safeguard
    Have operations verify work permit, isolation status and safe access.
  3. 3

    Inspect joint surfaces and tools

    Hazard
    Damaged sealing face or unsuitable equipment
    Safeguard
    Have competent personnel confirm sealing faces, tool condition and equipment instructions.
  4. 4

    Apply approved bolt tightening sequence

    Hazard
    Uneven loading, pinch points and excessive force
    Safeguard
    Take torque values and tightening sequence only from the approved engineering procedure and record completion.
  5. 5

    Quality checks and reinstatement

    Hazard
    Leakage or unsafe restart
    Safeguard
    Perform inspections, any specified approved leak checks and controlled operations handover.

Three critical pre-start verification points

  • Correct materials, gasket and design reference confirmed
  • Isolation and mechanical-completion records available
  • Approved bolt-up process and acceptance criteria available

Stop-work triggers

Stop for incorrect gaskets, damaged faces, missing approved torque references or uncertain isolation.

Frequently asked questions

Does this page provide standard torque values?

No. Values and sequence are engineering-specific and must come from an approved work pack.

Can the line be pressurized immediately after assembly?

Only after operations authorization, mechanical completion and any required examinations.

Official technical sources

These sources have jurisdiction-specific scope; verify local legal and engineering requirements.

Prepare your own document

Open the existing SERNEM generator to prepare and edit a site-specific method statement separately from this reference. Printing from the tool may require sign-in.

Open method statement generator →

Related field resources

Line breaking safety →JSA worksheet →