This paper describes the deformation of the sliding surfaces of a mechanical seal. That is, the values of the deformation due to the seal pressure and the oil film pressure are analyzed theoretically, in the analysis a mechanical seal is considered as a ring having rectangular section. Then the seal characteristics are tested by some analogical experiments in which a surface having the shape of theoretical deformation are used as a sliding surface of a mechanical seal.
And the followings are obtained.
1) The distribution of the oill film pressure between the sliding surfaces is varied by the deformed shape of the surfaces, then the necessary thrust force to seal the fluid is greatly influenced to the shape also.
2) It is necessary to balance the moments arround the center of the axial section for decreasing the amount of the surface deformation.
3) In the outside type seal a concave shaped surface which gives convex shape oil film pressure distribution shows more stable seal caracteristics than a plane shaped one.

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In this paper, frictional vibrations are experimentally investigated. The experiments are compared with the theoretical analysis in the previous report. The obtained results are as follows : 1. Amplitude characteristic from experiments is agree well with the theoretical analysis which includes a time effect. 2. The time effect of frictional characteristic is important factor to determine the limit of vibration. 3. The critical driving velocity V_c is given by a following equation; V_c=c/w_n² c; constant, w_n ; natural frequency.

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As the basis on grinding ceramic bobbins used for high frequency coils, the influence of a height distribution in cutting edges on grinding force and surface roughness is investigated when grinding ceramics, such as alumina, forsterite and steatite ceramics, by No.320 diamond wheels in which the conditions of cutting edges were prepared by grinding alumina. The results obtained are as follows : (1) Grinding force changes from 1 to 13kg depending upon dullness of edges and their number. (2) The horizontal grinding force consists of a force fracturing work material and a frictional force between work and wheel. Both the forces is nearly the same in magnitude. (3) Surface roughness is largely governed by the height distribution of cutting edges and by fractured depths which is inherent to work material. Initial roughness of 6μ is reduced to 2μ with the progress of wheel wear. (4) A No.600 wheel, having fine and numerous cutting edges with a comparatively uniform height distribution in cutting edges introduces better finish of less than 1μ in roughness and smaller fracture of work material. It is, therefore, applicable for thread grinding to use this diamond wheel.

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In order to clarify the effect of some elements (Te, Se, Bi, P, N, Sn, B, and In) and deoxidation procedures (MnS Killed, Si Killed, Al Killed, Ca deoxidation, Misch metal additive and Vacum melting) on tool life, the experiments on tool wear, cutting temperature and amount of oxidation in steel were done. The result was analyzed by a conventional method and a statistical approach.
This leads to the following conclusions.
(1) Te, Bi, B, and Se elements inclusion in low carbon steels improves machinability from the standpoint of tool life. On the other hand, Si and N additives decrease tool life. Sufficient attention should be paid to the interactions as well as the main effect.
(2) As to the deoxidation procedures, the tool life is in the order of MnS Killed, Al Killed, Si Killed and Ca deoxidation method.
(3) Assumming that the tool life is dependent on the thermal and mechanical characteristics of steels, the relationship among tool life, cutting temperature, and amount of oxidation was graphed and discussed. It is found that these results may explain the effects of some elements and deoxidation procedures on tool life systematically.

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In this paper, a new kind of single flank gear meshing tester with two master worms is newly introduced and studied.
In this method, two master worms are meshed with a tested gear on the same side tooth flanks.
One of them, the driving worm, is used to drive the gear and the other, the detecting worm, is used to detect the angular position error of the gear by means of detecting the axial fluctu-ation of the worm.
The relations between the angular position error of the gear and the axial fluctuation of the detecting worm are analyzed.
From the results of many experiments, the followings are clarified.
1. With this method the measurement of the angular position error of a high accuracy spur gear can be done quite easily.
2. With this method the errors of a fine pitch gear such as the gear with the module less than 0.1 may be measured also.
3. The measuring device can be made without difficulties.

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In grinding aluminium, the pores of grinding wheels are easily loaded with the fine ground off particles of aluminium. When high accuracy is required of the size and the finished surface of a work, there are many problems as to the grinding conditions concerned with loading phenomena.
In this experiment, Surface Grinder was used. The test specimens of aluminium (IS) were ground by aluminium oxide grain wheels, using various grinding fluids. The amount of loading aluminium, the grinding resistance, and the roughness of the ground surface were measured. Especially, the amount of loaded aluminium on the wheel surface w as estimated by chemical analysis.
As a result, aluminium is able to be ground fairly good by aluminium oxide abrasive grain, if the suitable grinding fluids which have a good boundary lublicating ability for aluminium and alminium oxide are applied. Namely, in the case of suitable grinding fluids, the quantity of loaded aluminium on the aluminium oxide wheel does not increase so evilably. And it is found that the loaded aluminium on wheel has less value in the use of soluble type fluids, and also, the roughness of finished surface largely depends on the degree of loading.

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