Dũa kiểm độ cứng thép Yamamoto HRC (8) (Mã đặt hàng: 14123)

Yamamoto Scientific Tool Laboratory Co., Ltd. was established in 1939. It was the first dedicated manufacturer of standard test blocks in Japan, and has maintained its reputation as the best and foremost company in this field.

It is well known that hardness testers of Shore, Brinell, Rockwell and Vickers are used widely for measurement of hardness of various metal materials. They are obliged very often to know the rough hardness of articles on site and find it very inconvenient for various reasons. In such case, Yamamoto's hardnester will be very useful and provide easy as well as prompt measurement of articles’ hardness anytime and anywhere.

Constitution of Hardnester

Yamamoto's hardnester consists of two parts; touch measure and shank. Ultra-hard steel round material has been adopted for the touch measure and tapered as shown in the Fig. 1. It has been formed to be a file fit for scratching and a specified hardness has been given to it. Unstable composition causing the fluctuation in hardness has been removed completely from it, resulting in assuring users of extremely stable hardness. Touch measure with odd and even hardness numbers are screwed in the both ends of the shank. The shank bears criterion hardness of the hardnester. As shown in Fig. 1, symbolized bands of clock figures are combined and indicated at both ends of knurling tool so that users may know the hardnester number number at first sight.

Principle and Use of Hardnester

When the hardnester is pressed against the object article with forefinger (4.5-4.8 kg in the case of male adult), it slips and does not penetrate in it so far as the hardness of the hardnester is lower than the object article to be measured. However, when the hardness of the hardnester is slightly higher than the object article to be measured, it will start penetrating in it rapidly. The above relations are clearly known as the position of the forefinger goes near to the touch point of the touch measure and the article. If hardnesters of different hardnesses are provided, it will be possible to measure every hardness of articles very easily and promptly.