The mechanics training shall consist of a minimum amount of lecture and a lot of hands on exercises. We also have a 45min. videotape on bolting which reviews all of the discussed topics (optional). Objectives Discuss the relationship of Design, Assembly & Performance to Bolted Joints. Using a full sized flanged joint the participants will go from discussion to application! In small groups using different assembly procedures students will have instant feedback of results by way of our instrumented demonstration flanged joint! Performance Introduce performance criteria and failure modes Leaks Gaskets Fatigue Loosening Who should attend Anyone tightening bolted joints; mechanics and engineers! We can also customize any of the seminar offerings for your particular needs.

 Outline of one day Mechanics Seminar

• Preload
• Definition
• Importance of Preload - Leak prevention, improve fatigue life, prevent loosening, joint reliability

• Assembly
• Torque- Prerload relationship (T = KDF_P)
• Discuss the effect on preload of:
• Surface condition- external threads, tapped threads, bearing surfaces
• Lubricant and application
• Washers
• Materials
• Calibrated torque versus mechanics feel or slugging
• Uniform torque application

Using a load cell, two or three exercises will be performed which illustrate the importance of the assembly factors discussed above.

1. Mechanics feel Vs. Calibrated torque - three mechanics tighten a fastener in a load cell until it "feels tight ". Record and discuss the resulting preloads.
2. Lubricated bolt versus dry. Simulate both conditions in a load cell.
3. Lubricate threads only versus lubrication of threads and bearing surface of turned element.

 Second Discussion Period

• Sealing surface finish
• Preload required to seal
• Assembly considerations
• Fit-up,
• Surface irregularities
• Tightening - tightening patterns, number of passes

Using instrumented bolts the preload in each of the fasteners in the gasketed joint will be measured and displayed in real time on our data-logging computer after each pass. The discussion is usually very active as the participants try to apply new information to 'generally accepted as correct' prior knowledge.

1. Mechanics feel and experience - Allow a mechanic to tighten the gasketed joint using skill of the craft; that is the mechanic uses his judgment and feel to determine: the tightening sequence, the number of passes and the load level. Measure and discuss the results.
2. Tighten the gasket joint using a specified procedure, which includes torque control, lubricant application, tightening sequence and number of passes. Discuss the results and compare to the mechanics feel.