Monitoring of L-Shape Bolted Joint Tightness Using Thermal Contact Resistance

The tightening operation with a bolt heater has advantages surpassing those of other tightening methods. Currently, a bolt heater is mainly applied to tighten huge bolts that cannot be clamped by other means, and the tightening operation is usually supported by the expertise of skilled workers. In this paper, a numerical approach is presented to aim at a broader use of bolt heater technique by elucidating the tightening mechanism. The effects of thermal contact resistance existing around a bolted joint are taken into account for a better accuracy in the numerical analyses. Based on the numerical results obtained, a series guideline to help the tightening operation when performed by less skilled workers is proposed.

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Interface pressure distributions and thermal contact resistance of a bolted joint

Proceedings of The Royal Society A Mathematical Physical and Engineering Sciences ◽

10.1098/rspa.2005.1452 ◽

2005 ◽

Vol 461 (2060) ◽

pp. 2339-2354 ◽

Cited By ~ 13

Author(s):

M Tirovic ◽

G.P Voller

Keyword(s):

Cast Iron ◽

Contact Resistance ◽

Thermal Contact Resistance ◽

Thermal Contact ◽

Conductive Heat ◽

Bolted Joint ◽

Interface Pressure ◽

Pressure Distributions ◽

Area Of Interest ◽

Wide Range

The paper studies interface pressure distributions and thermal contact resistance (TCR) of a large automotive bolted joint. The research was initiated by the need to determine accurately conductive heat dissipation from a commercial vehicle disc brake. The main area of interest was the conduction between the grey cast iron disc and the spheroidal graphite cast iron wheel carrier. The bolt clamp forces and interface pressure distributions were investigated theoretically and experimentally. Finite-element analyses and pressure-sensitive paper experiments provided very similar interface pressure distributions. TCR change with interface pressure was studied experimentally, by conducting numerous temperature measurements. The derived linear relationship is of generic nature, enabling the calculation of the TCR for a variety of engineering bolted joints, over a wide range of interface pressures.

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Bolted Joint Interface Pressure for Thermal Contact Resistance

Journal of Applied Mechanics ◽

10.1115/1.3408817 ◽

1971 ◽

Vol 38 (2) ◽

pp. 542-545 ◽

Cited By ~ 20

Author(s):

T. L. Bradley ◽

T. J. Lardner ◽

B. B. Mikic

Keyword(s):

Contact Resistance ◽

Thermal Contact Resistance ◽

Thermal Contact ◽

Three Dimensional ◽

Joint Interface ◽

Bolted Joint ◽

Interface Pressure ◽

Flat Plates ◽

Pressure Distributions ◽

Photoelastic Analysis

One of the parameters needed to calculate the thermal contact resistance across a bolted joint is the interface pressure distribution between the plates of the joint [1, 2]. As part of a study [3] on thermal joint conductance, a three-dimensional photoelastic analysis using the stress freezing technique was used to predict the interface pressure. Nine bolted joint geometries were investigated using smooth flat plates of photoelastic material and equal thickness. The resulting interface pressure distributions which are presented are sufficiently accurate for the calculation of thermal contact resistance.

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