Cemented carbide anvil is an important component of synthetic diamond device. It bears high temperature and high pressure alternating load in the process of diamond synthesis. Its life directly determines the production cost of diamond synthesis. The synthetic industry of synthetic diamond in China mainly adopts hexahedral top synthesis process, which belongs to static pressure catalyst method. The basic principle is that six carbide anvils are used on the six faces respectively, and the action area is on the high-pressure cavity composed of hexahedral pyrophyllite, so that the graphite in the cavity can be transformed into diamond by high temperature and high pressure under the action of catalyst.
Zhejiang Hengcheng cemented carbide Co., Ltd. is one of the enterprises which developed and produced cemented carbide anvil earlier in China. The quality level and stability of the products are in the leading position in China. The annual output of cemented carbide anvil can reach more than 200 tons.
The company always attaches great importance to the quality control of anvil products and the research and development of new products. At present, DC10 series cemented carbide anvil developed independently has become one of the leading products of the company, which has been used by customers at home and abroad and has been well received. Hengcheng cemented carbide anvil has become the preferred brand of diamond manufacturers at home and abroad.
|Grade||Cobalt Content||Physical & mechanical properties|
Model specification and tolerance requirements
matters needing attention:
1. Elimination of internal stress
The residual surface internal stress of anvil after finish machining should be aged before use. The methods can be divided into natural aging, oven thermal aging and oil boiling thermal aging. Among them, the natural aging time is not less than one month, the oven thermal aging temperature is controlled at 250 ℃, and the time is not less than 72 hours.
2. Assembly requirements of anvil
The taper of anvil and steel ring shall be consistent, and the contact surface shall not be less than 90%; the press mounting height shall be reasonable, and the press mounting height of anvil with diameter less than or equal to 127mm shall be 8-10mm, and that of anvil larger than 127mm shall be 10-12mm.. The point contact between anvil and large and small cushion blocks should not occur to avoid stress concentration.
3. Requirements for raw materials
The machining accuracy of steel ring and large and small cushion blocks shall meet the requirements. The finish of steel ring inner wall shall not be greater than Ra1.6. The roundness and taper shall be consistent with the shape and position tolerance of anvil. The parallelism of large and small gaskets shall be less than or equal to 0.02mm, and the hardness shall be moderate.
The roasting temperature and time of pyrophyllite should be moderate to prevent blasting accidents caused by poor pressure transmission performance and high moisture content of pyrophyllite. The surface of conductive steel ring is required to be free from corrosion, edge crack, and no blue baking phenomenon after baking. Attention should be paid to moisture-proof storage.
4. Requirements for equipment
The press should have good adjustment accuracy, no leakage is allowed, and the synchronization and neutral deviation shall not exceed 0.2mm.
5. Requirements for operation
When assembling on the machine, the pyrophyllite should be checked for cracks, impurities, and whether the thin and thick steel sheet is installed in wrong or reverse way. The surface of 6 anvil should be cleaned to avoid squeezing hammer and hitting. Before each anvil is combined, all four surfaces must be delimited to prevent caving hammer blasting. When the idle travel is advancing, check the action of 6 cylinder, whether the fixed cylinder has misoperation and whether the moving cylinder is suspended when the moving cylinder is in place. When the heat is stopped for pressure relief, the pressure holding time shall not be less than 1 minute to prevent the pressure relief and venting gun.