Table of Contents

  1. Purpose
  2. General
  3. Responsibilities
  4. Work Instructions
  5. Flowchart
  6. References
  7. Attachments

1. Purpose

The purpose of this work instruction is to lay down the requirements for the development, control and application of tie-in schedules.

This work instruction is applicable for all projects containing tie-in activities unless otherwise directed by the Project Manager.

2. General

A tie-in schedule is a document that ensures that all requirements of a technical and planning nature, in relation to the design, fabrication and installation of tie-ins is compiled, reviewed/com­mented upon and formally issued.

Tie-ins of piping and underground piping lines may be required within/to an existing plant as a revamp exercise, as an extension exercise or when an additional adjacent plant is designed, where interconnections with an existing plant are necessary.

3. Responsibilities

The Project Manager is responsible to assure that this work instruction is applied and for the approval of formal issues (e.g. to the Client) of the tie-in schedules.

The Project Engineer is responsible to ensure that the tie-in schedules are prepared in his section, commented upon, updated and issued in accordance with this work instruction and Client's requirements. This responsibility includes the coordination of all involved dis­ciplines.

The Piping Designer and Underground Piping Designer are responsible for the field verification and subsequent development of input to the tie-in schedules.

The Planning Engineer is responsible for providing the installation planning input and for monitoring any subsequent forecast changes.

The Process Engineer is responsible for provision of the necessary input or "construction data" to satisfy process, operational and safety requirements and to review the proposed configurations.

The Piping Engineer is responsible for providing the "testing" input and for reviewing the piping wall thicknesses, classifications and con­figurations.

The Construction Coordinator/Construction Manager is responsible for review of tie-in criteria and testing requirements.

4. Work Instructions

The Project Engineer shall mark the necessary tie-ins on the P&ID's. (Ref. 6.1).

The Project Engineer shall develop a tie-in numbering system that satisfies Client's requirements.

The Project Engineer shall add the tie-in numbers to the P&ID's (also referred to as EFD's or EFS's) and shall complete columns 1,2,3,4 and 5 of the tie-in schedule. (See Attachment 1).

The Project Engineer shall make an internal issue (Ref. 6.5 and 6.6) of the tie-in schedule(s) to the Process, Planning and Piping Engineers and shall submit the original to the Piping Designer while at the same time, keeping a copy in the project engineering file. This internal issue shall be coded "OA" and carry the description:

"For Information and Piping Design Updating".

The Planning Engineer shall mark-up a copy of this issued tie-in schedule for column number 23 of the tie-in schedule and submit this to the Project Engineer. This marked-up print shall be signed and dated by the Planning Engineer.

The Piping Designer shall carry out a field verification (site survey) to determine the accuracy of existing plant piping design documents. If discrepancies/variations are encountered, the Piping Designer shall mark-up the existing documents to reflect the actual sit­uation.

The Piping Designer shall complete columns 6, 7, 8, 10, 11 and 13 of the tie-in schedules and, where appropriate, mark up comments for the P&ID's. These mark-ups and the original of the tie-in schedule shall be sent to the Project Engineer.

The Project Engineer shall discuss the tie-in schedule, particularly columns 9 to 12 inclusive, with the Client so as to collect and record the proper information.

The Piping Engineer shall, together with the Process Engineer and the Construction Coordinator/Construction Manager, complete the construction data, columns 14 to 22 inclusive, of the tie-in sched­ule.

For tie-ins where new lines tie into existing lines by means of a weld new-old: it shall be established with Client where Company 's work in relation to hydraulic testing and flushing is limited to, e.g. tie-in point will be 100% X?rayed or flushing/testing to nearest flange in existing line with indication of location of this flange. The above philosophy shall be attached on a separate sheet to the tie-in schedule. Also, responsibility for a failure in testing and subsequent repair of existing lines shall be clearly stated (include also test pressure for the part of existing systems that will have to be retested).

After receiving the necessary data from the Piping Designer and the Planning Engineer, the Project Engineer shall verify, update and complete as appropriate all data of the tie-in schedules.

The Project Engineer shall then make the first formal issue of the tie-in schedule. The issue description shall read:

"Preliminary for Comments" or "For Client's Comments".

The distribution shall include, as a minimum:

  • the Planning Engineer
  • the Piping Engineer
  • the Process Engineer
  • the Piping Designer
  • the Underground Piping Lead Designer
  • Construction Coordinator/Construction Manager
  • the Client.

The comment period shall be specified.

During the comment period, the Project Engineer shall interface with the discipline specialists and the Client so as to resolve any queries and ensure that comments are submitted in time.

At the conclusion of the comment period, the Project Engineer shall update the tie-in schedules and reissue (Ref. 6.1). The issue description shall be:

"For Detail Design".

The Project Engineer shall establish a Project "Master" for further mark-ups as the project progresses.

The Project Engineer shall make regular reissues, as necessary, of the tie-in schedules in combination with the reissues (updates) of the P&ID's and line tables. (Ref. 6.1).

The Project Engineer shall maintain a close interface with the discipline specialists and the Client in order to review column 23 and, if required, to complete column 24 of the tie-in schedule (See attachment 1).

The Project Engineer shall continue to refine the information and make regular reissues as necessary until all piping isometrics have been completed and issued for construction.

The last issue, after distribution, shall be kept in the project files as records until the project close-out. (Ref. 6.2).


5. Flowchart



6. References


  Number Title Level
6.1 CM-PE-002 Preparation of PFD's, EFD's and Related Documents 2
6.2 CM-PE-111 Final Disposition of Project Documents 2
6.3 CM-PE-705 Subcontracts Procedure 2
6.4 BN-EP-338C Piping Material Control Piping Design Section 3
6.5 BN-W-U012 Document Issue Code and Change Identification 4
6.6 BN-W-UE-301 Numbering of Project Documents 4

7. Attachments

  1. Tie-in Schedule - Standard Form (BN-UE-302)
  2. Tie-in Schedule - Example