Huanghua pear, the scientific name of the scented rosewood, fragrant wood. Latin name: Dalbergia odorifera T.Chen
Product name: scentedrosewood
Huanghuali logs are good wood for making mahogany furniture, and there are very few existing ones on the market. Most of the things we can see are mostly yellow pears from Vietnam. Because Vietnam and Hainan are geographically close to each other and are basically at the same latitude, Vietnamese huanghuali is very similar to Hainan huanghuali, especially wood from eastern Vietnam and Hainan across the sea. How to identify the two types of wood can be referred to the following five points:
First, the relative texture of Hainan huanghuali (brown eye) is fine, and the texture of Vietnamese huanghuali is thicker.
Second, Hainan huanghua pear tastes a little bigger, that is, the fragrant flavor, while the Vietnamese huanghua pear has a slightly less scent.
Third, Hainan huanghua pear texture is good, more grimace, so-called tiger skin pattern, Vietnamese huanghua pear is relatively poor.
Fourth, the color is also different between the two, Hainan huanghuali color is darker, Vietnamese huanghuali lighter.
5. From the material point of view, the Vietnamese huanghuali tree is coarse, and the Hainan huanghuali is generally small in diameter. The diameter of the Vietnamese huanghuali heartwood seen today is mostly 20-40 cm.
The difference between the above two types of wood is relatively speaking, and it is necessary to identify the wood after partial planing. The specifics must be subject to the real thing!
Since the texture and aroma of Hainan huanghuali and Vietnamese huanghuali are basically the same, the biggest difference is analyzed from the perspective of density and color. The density of Hainan huanghuali is high, the texture is very fine and the color is heavy, and the scent is thick. The texture of Vietnamese huanghua pear is relatively loose, with more needles and noses, lighter color and lighter scent. It is difficult for consumers who have no experience to distinguish it, and the price gap between Vietnam and Hainan huanghuali wood is quite large.
The full ceramic ball bearings listed below are supplied with rings and balls made from zirconium dioxide (ZrO2). These zirconia bearings are available as full complement (no cage) or with cages made from PTFE, PEEK or 316 stainless steel.
These are non magnetic, non-conductive and highly corrosion resistant to most chemicals although ZrO2 bearings are not recommended for prolonged contact with steam. Full complement bearings or those with a 316 stainless cage can be used up to 400°C while bearings with a PEEK or PTFE cage can cope with temperatures of up to 250°C. For temperatures below -70°C, PTFE or 316 stainless steel cages are preferred. Standard radial clearance for full ceramic bearings is C0 but other clearances can be supplied to order.
ZrO2 ceramic bearings are generally used for their extreme temperature capabilities, excellent corrosion resistance or non-magnetic properties. Other sizes can be supplied on request.
The Description of Ceramic Bearings:
Compared to steel, Ceramic ball Bearings have many specific advantages. They offer superior corrosion and heat resistance, higher dimensional stability, and lower density, which facilitate high speed. Ceramics are superior to steel in heat and corrosion resistance, and are lightweight and extremely hard as well. Consequently, ceramic rolling bearings can be used in environments where conventional steel bearings cannot. That is to say, the superiority of these bearings makes it possible that they can be applied in some special environments.
Firstly, they can be used in corrosive environments. Compared to stainless steel bearings, hybrid and all Ceramic Bearing lasted three and twenty times longer respectively. It is presumed that water readily adheres to silicon nitride and forms a better lubrication film, leading to extended bearing life.
Secondly, they can be performed in corrosive agents. Generally, silicon nitride has excellent corrosion resistance. However, corrosion resistance varies depending on the type and quantity of sintering additives, and certain corrosive agents decrease in hardness and flexural strength. In such situation, it is can be proved that the carbide-based ceramic bearings are the most effective.
Thirdly, they can be used in high-temperature vacuum. An all-silicon nitride Ball Bearing with a self-lubricating laminated cage (mainly composed of MoS2) and with MoS2-coated rings and balls proved superior in durability in a high-temperature vacuum environment. Compared with the hybrid bearings, the all-ceramic bearing was superior in both dynamic frictional torque and life.
Fourthly, they can be performed with poor lubrication. As ceramics are extremely hard and have outstanding wear resistance, they outperform other materials in bearing life without lubrication. According to a test, the steel bearing seized within a short period while the hybrid and all 627 Ceramic Bearings, though sustaining wear, did not. And the all-ceramic bearing sustained considerably less wear than the hybrid bearing, indicating that its endurance life is much longer.
Cermic Ball Bearing,Full Ceramic Bearing,Hybrid Ceramic Bearing,Self-Aligning Full Ceramic Ball Bearing
Shijiazhuang Longshu Mechanical & Electrical Equipment Trading Co., Ltd. , https://www.lsjgbearing.com