#VDI 2230 TIGHTENING FACTOR GENERATOR AND REACTOR#
#VDI 2230 TIGHTENING FACTOR FULL THREE DIMENSIONAL#
#VDI 2230 TIGHTENING FACTOR GENERATOR SUPPORT BOLTING#

These are guidelines based upon actual experience and measurements made in the field. Tightening factor and tool precision discrepancies are available from the SR1 - VDI 2230 database. Deutsch/englisch Issue German/English VDI-Handbuch Produktentwicklung und Konstruktion VDI. VEREIN DEUTSCHER INGENIEURE Systematische Berechnung hochbeanspruchter Schraubenverbindungen Zylindrische Einschraubenverbindungen Systematic calculation of highly stressed bolted joints Joints with one cylindrical bolt VDI 2230 Blatt 1 / Part 1 Ausg.

Vdi 2230 Tightening Factor Full Three Dimensional

However, these require that the model is correct. Recently full three dimensional finite element models have been used to determine the relationship between the nominal applied load and the resulting critical tooth root stress within threaded connections. The bolts must be designed such that the joined sectionStress analysis of threaded connections has been a widely researched topic for many years. A bolted joint is a separable joint between two or more components using one or more bolts.

Three very different connection types were studied, these were large diameter thick and thin walled connections and a regular ISO metric threaded bolt. For these reasons an experimental investigation of preload due to applied torque in threaded connections was carried out. Stress corrosion cracking could also become a significant feature even without fatigue loading. If large tensile mean stresses are not taken into account in fatigue analysis, unconservative fatigue life predictions can result. The level of preload applied during make-up of threaded connections will directly effect the stress moreВ В» distribution within the connection as a whole, and will also determine the level of mean stress of an oscillating fatigue stress.

The tightening factor is a measure of the scatter in a bolt's clamp force as a result of the tightening method used to tighten the fastener. Readers who wish to put the standard to use are urged to refer to the complete standard that contains all information, figures. Important NoteThis summary of the VDI 2230 Standard is intended to provide a basic understanding of the method. In the hydraulic torque-controlled tightening method, the torque tool stops when reaching a.Overview of VDI 2230An Introduction to the Calculation Method for Determining the Stress in a Bolted Joint. В«В lessVDI 2230 tightening factor friction optimized: A 1.1 1.2. Conclusions are that large circumferential stresses may exist close to the rotary shoulder interface due to applied preload, and fatigue analyses should consider whether packing material remains inert during service - otherwise the initial stress analysis may no longer be appropriate.

Vdi 2230 Tightening Factor Generator Support Bolting

Vdi 2230 Tightening Factor Generator And Reactor

A Westinghouse Owners Group funded program was established to develop in situ ultrasonic examination techniques to determine steam generator support bolting integrity at the head-to-shank and first-thread locations. One of the issues deals specifically with high-strength bolting materials, which are vulnerable to stress corrosion cracking. Subsequently, the bolting issues were addressed in generic issue B29. The US Nuclear Regulatory Commission concerns for high-strength bolting were identified in NUREG-0577, ''Potential for Low Fracture Toughness and Laminar Tearing moreВ В» in PWR Steam Generator and Reactor Coolant Pump Supports,'' which was issued for comment on unresolved safety issue A-12. These bolts are part of the pressurized water reactor steam generator supports at the integral support pads (three per steam generator, with each pad housing six, eight, or ten bolts depending on the design).

The ability to insure required preload in normal service is, consequently, an important question. These studies have been performed under controlled, laboratory conditions. The literature also shows the uncertainty associated with use of torque to establish preload is typically between moreВ В» 10 and 35%. The extensive literature on threaded fasteners provides sound guidance on design and torque specification for closure bolts.

Several coupling bolts at the three flanged connections on most units have experienced failures: 127 mm (5 in) diameter bolts joining the main shaft to the runner hub, 76 mm (3 in) diameter bolts joining the adapter cone to the runner hub, and 114 mm (4.5 in) bolts joining the moreВ В» adapter cone to the stub shaft. This paper focuses on the fastener failures. These problems have been discussed in earlier papers. The eight turbines have experienced several failure problems, including shaft cracking, stay vane cracking, and failure of coupling bolts. В«В lessThe Ozark and Webbers Falls powerhouses were constructed on the Arkansas River between 19.

The degree of preload in the coupling bolts has been varied with some uncertainty about the optimal preload. There is significant chloride content in the river water and the different connections have different degrees of protection from the corrosive environment. Stainless steel was used in replaced fasteners to improve corrosion resistance. As the bolts have been replaced over time, increased care has been taken to improve the fastener geometry to extend the fatigue life.