DIMENSIONAL CONTROL PROCEDURE

TABLE OF CONTENTS

1. Objective

2. Scope of application

3. Implementation responsabilities

4. References

5. Terminology

6. Development

7. Historical changes

NOTE 1: It is the users responsibility to ensure that you use the current revision. NOTE 2: No other total or partial reproduction or transmission is permitted without permission of the General Manager or their representative.

DIMENSIONAL CONTROL PROCEDURE

1. OBJECTIVE

This procedure defines the guidelines for the dimensional control and verifies

dimensional tolerances in Pressure Vessel in accordance with the provisions of the

ASME Code Section VIII.

2. SCOPE OF APPLICATION This procedure applies to the manufacture of Pressure Vessel made by xxx . for the

project xxx, whose manufacturing stage to be held in xxx production to supply the xxx

3. IMPLEMENTATION RESPONSABILITIES Project Manager: He must assure that the qualified personnel and other resources (materials,

equipment, etc.) needed for the execution of the project is available.

Quality Control Chief: He manages the Project Quality Plan and ITP. He is responsible to assure the resources for the correct execution of this

procedure.

Quality Inspector: He is responsible for execution of the Inspection and Test Plan. Responsible for implementation of this procedure and its implementation in

accordance with the requirements of the reference standard.

Responsible for informing the supervisor of manufacturing /assembly finding deviations outside tolerance.

He informs the Quality Chief about any finding. He cooperates in the organization of the final Quality Dossier.

NOTE 1: It is the users responsibility to ensure that you use the current revision. NOTE 2: No other total or partial reproduction or transmission is permitted without permission of the General Manager or their representative.

DIMENSIONAL CONTROL PROCEDURE

4. REFERENCES ASME Code Section VIII, Div. 1 Standard ASTM A6/A6M

5. TERMINOLOGY

5.1 Tolerance: Dimensions, properties, or conditions may vary within certain practical limits

without significantly affecting functioning of equipment or a process. Tolerances

are specified to allow reasonable leeway for imperfections and inherent variability

without compromising performance.

5.2 Peaking: Local deviation from the theorical form, associated with the distortion caused by

welding vertical joints tanks shell.

5.3 Banding: Local deviation from the theorical form, associated with the distortion caused by

welding in the horizontal joint on the tank shell.

6. DEVELOPMENT

6.1 EQUIPMENT / TOOLS TO USE

Templates (minimum length: 900 mm) for control of peaking and banding.

Flexometer

Topographic equipment

Other manual and auxiliary measurement tools (squares, plumbs, etc.)

Personal protection equipment

NOTE 1: It is the users responsibility to ensure that you use the current revision. NOTE 2: No other total or partial reproduction or transmission is permitted without permission of the General Manager or their representative.

DIMENSIONAL CONTROL PROCEDURE

6.2 EXECUTION - DIMENSIONAL CONTROL IN WORKSHOP a) For inspection after welding, dimensional inspection shall be performed as

follows:

Tolerances for Formed Heads The inside surface shall not deviate outside the shape by more

than 1.25% of the inside diameter nor inside the shape by

more than 0.625% of the inside diameter. (ASME VIII Div.1

UG-81).

Out of Roundness of shell The maximum permitted ovality tolerance (Dmax Dmin) shall

not exceed 1% of the nominal diameter of the vessel.

If you have an opening, then the tolerance can be increased by

2% x d (d = diameter of opening), if the measurement is taken

within a distance of d from the axis of the opening. (ASME

VIII Div.1 UG-80).

Nozzles Control Nozzles (excluding manholes) shall be installed within the

following tolerances:

- Specified projection from outside of tank shell to extreme

face of flange: 1% nominal dimension.

- Elevation of shell nozzle or radial location of a roof nozzle:

1% nominal dimension.

- Flange tilt in any plane, measured on the flange face: 0.5

degree deflection is permissible.

- Flange bolt hole orientation: 3 mm (1/8 in.).

Local deviations control Local deviations from the theoretical shape (for example,

weld discontinuities and flat spots) shall be limited as

follows.

- Deviations (peaking) at vertical weld joints shall not exceed

1% of the nominal diameter of the vessel.

NOTE 1: It is the users responsibility to ensure that you use the current revision. NOTE 2: No other total or partial reproduction or transmission is permitted without permission of the General Manager or their representative.

DIMENSIONAL CONTROL PROCEDURE

Peaking at vertical weld joints shall be determined using a

horizontal sweep board 900 mm (36 in.) long. The sweep

board shall be made to the nominal radius of the tank.

- Deviations (banding) at horizontal weld joints shall not

exceed 1% of the nominal diameter of the vessel. Banding

at horizontal weld joints shall be determined using a straight

edge vertical sweep board 900 mm (36 in.) long.

NOTE 1: It is the users responsibility to ensure that you use the current revision. NOTE 2: No other total or partial reproduction or transmission is permitted without permission of the General Manager or their representative.

This procedure defines the guidelines for the dimensional control and verifies dimensional tolerances in Pressure Vessel in accordance with the provisions of the ASME Code Section VIII.This procedure applies to the manufacture of Pressure Vessel made by xxx . for the project xxx, whose manufacturing stage to be held in xxx production to supply the xxx