著者
高木 知弘 福岡 俊道
出版者
一般社団法人 日本高圧力技術協会
雑誌
圧力技術 (ISSN:03870154)
巻号頁・発行日
vol.41, no.3, pp.106-114, 2003 (Released:2003-07-24)
参考文献数
17
被引用文献数
2

In these environmentally sensitive times, bolted flanged joint design that makes the leakage from a joint a design criterion has been investigating. However, achieving uniform bolt preload is difficult when tightening pipe flanges with a number of bolts, even if the appropriate amounts of bolt preload can be calculated following established design rules. A guideline for bolted flange joint assembly has been presented by ASME. However, the guideline needs repeated bolt-up operations to get uniform preloads. In this study, in order to establish a more effective bolt assembly guideline, numerical calculations are systematically executed by using three-dimensional finite element analysis. The analytical objects are pipe flanges of class 150lb and 300lb raised face slip-on welding type specified in JPI with a compressed asbestos sheet gasket inserted. The variations of bolt preload and contact pressure distributions at the gasket bearing surface during bolting up are estimated.
著者
福岡 俊道
出版者
公益社団法人 日本マリンエンジニアリング学会
雑誌
マリンエンジニアリング (ISSN:13461427)
巻号頁・発行日
vol.48, no.6, pp.847-853, 2013-11-01 (Released:2014-11-01)
参考文献数
10
被引用文献数
1

A bolt heater is frequently applied to tighten large and critical structures with large bolts that cannot be clamped by any other means. In addition, multiple bolts can be tightened simultaneously by using the same number of bolt heaters. When bolt heaters are used for tightening large bolts, they are usually placed vertically because the target bolts are installed in the same vertical direction. In this study, the applicability of horizontally plated bolt heaters is examined to promote its broader use. It is found from tightening experiments that the bolt heater technique can be applied for bolts placed horizontally or on an inclined plane. Based on the experimental results, a guideline is proposed for the cases of bolt heaters used in the above-mentioned manner. It is also shown that the bolt heater technique can be an effective assisting method to JIS B2251, “Bolt tightening procedure for pressure boundary flanged joint assembly”.
著者
福岡 俊道 野村 昌孝
出版者
一般社団法人 日本機械学会
雑誌
日本機械学会論文集 (ISSN:21879761)
巻号頁・発行日
vol.83, no.851, pp.17-00018-17-00018, 2017 (Released:2017-07-25)
参考文献数
13
被引用文献数
1

Titanium and titanium alloys have a lot of excellent characteristics when used for the parts and components of machines and structures. As for bolted joints, however, they are used only for some limited cases because of the high cost. Their specific characteristics, e.g., low weight and high resistance to corrosion, are highly attractive from the engineering point of view. In this paper, thermal contact coefficients at the interface composed of titanium and titanium alloys are measured, and the empirical equations for evaluating the coefficients are derived in the same form proposed in the previous papers. Then, heating experiments of bolted joints, tightened by titanium bolts, are conducted to examine how the bolt preloads vary when subjected to thermal loads, and the bolt preload variations are compared to the case tightened by carbon steel bolts. In the next place, aiming at a broader use of titanium and titanium alloy bolts, numerical analyses are performed to demonstrate the effectiveness of those bolts by incorporating the foregoing thermal contact coefficients into the finite element formulation. The numerical results are favorably in good agreement with the experimental ones, and they suggest that threaded fasteners made of titanium alloys can be favorably applied to the joints whose clamping forces are likely to decrease when subjected to thermal loads.