Engineering & Inspection Services (EIS) is a full service design and engineering firm based in Metairie LA. In addition to engineering and design, EIS also provides specialty services such as equipment bolt torque procedure generation and review.

Controlled bolt torquing is the most common method for developing a certain level of bolt tension. A well written bolt torque procedure should be utilized on equipment where leaks can be critical to safety and operations. We are all well aware of the unintended consequences resulting from improper torque on a bolted joint. Some of the basic steps that should be incorporated in every torque procedure are:

1. Check the condition of the flange surface after cleaning.• All burrs and nicks shall be repaired.• Radial grooves across the flange surface

shall be repaired by refacing or be replaced.2. Always use hardened steel washers on the

flange surfaces.3. Always use new studs, nuts and gaskets.

• Do not mix old studs and nuts with new ones.

4. Clean threads on all new studs and nuts.5. Check the alignment of the flanges.

• Bolts should move freely in their respective holes without binding.

6. Lubricate all bolts and nuts liberally with the specified lubricant.• Always know the lubricant type being used.

7. Follow the specified number and type (star, circumferential or combination pattern) of passes required for optimum seal.

A QA/QC procedure should also be developed to ensure that the torquing procedure has been followed properly. This is especially the case during TAR activities, where numerous pieces of equipment may require controlled torquing. Also, it is not unusual to develop a specific torque procedure for a historically problematic piece of equipment. In these cases, an operational start up procedure and/or hot bolting may also be incorporated to ensure a leak free start up.

EIS has extensive experience in developing torque values and procedures. Feel free to contact us if you have any questions pertaining to a specific application. We would be glad to discuss your concerns free of charge. If additional services are needed, EIS can provide these at a reasonable cost. References are available upon request.

For more information:Tonya ChauvinBusiness Development Managertchauvin@eisllc.net

Engineering & Inspection Services, LLC 3501 N Causeway Blvd., Suite 900Metairie, LA 70002T: (504) 837-3310F: (504) 837-3889www.eisllc.net