FAQ

Q1.O que é tempo de garantia para OS produtos Sinowon exportados para o Mercado internacional?


Answer: in China, we supply 12-month as warranty time for the customers, the date time is started to count from the machine installed and acceptance checked. As for instruments exported to international market, it is 15-month for warranty time, but it is started to count from the shipping time, the shipping time will be declared and found on the bill of loading or airways.


Q2!Quem inventou o método de testes Rockwell para testes de materiais?


Answer: It is acceptable that Mr. Hugh M. Rockwell (1890–1957) and Mr. Stanley P. Rockwell (1886–1940) from Connecticut in the United States co-invented the "Rockwell hardness tester," a differential-depth machine. They applied for a patent on July 15, 1914.[4] The requirement for this tester was to quickly determine the effects of heat treatment on steel bearing races. The application was subsequently approved on February 11, 1919, and holds U.S. Patent 1,294,171.


Q3!Qual é a diferença entre Rockwell e Superficial Rockwell?


A fundamental distinction is made between two types of Rockwell method: Regular Rockwell (or Rockwell) and Superficial Rockwell (or Super Rockwell):


1. Rockwell: The perforce (or p reload) is always 10 kgf, while the total test force (also referred to as main force or load) can vary between 60, 100, or 150 kgf.
2. Super Rockwell: The perforce is 3 Kgf, while the main force can vary between 15, 30, or 45 Kgf.


Métodos de ensaio Rockwell. Super Rockwell.
Força de pré-carga 10kgf. 10kgf. 10kgf. 3kgf 3kgf 3kgf
Força principal 150kgf 100kgf 60kgf 45kgf. 30kgf. 15kgf



Os valores de Dureza determinados pelo Super Rockwell podem ser convertidos EM valores Rockwell e vice-versa.O método Superficial Rockwell FOI inventado NOS EUA, ONDE a SUA utilização é significativamente Mais Comum do que Na Europa.É particularmente adequado para o USO EM testes de Dureza de Componentes e camadas finas, Ou com espécimes Cujo valor de Dureza calculado está fora Da escala regular de Rockwell.


Rockwell and Superficial hardness testing shall be performed in accordance with the latest revision of ASTM E18.

There are two general classifications of the Rockwell test: the Rockwell hardness and the Rockwell superficial hardness test. In the Rockwell hardness test the preliminary test force is 10 kgf. Total test forces are 60 kgf, 100 kgf and 150 kgf. In the Rockwell superficial hardness test, the preliminary test force is 3 kgf and total test forces are 15 kgf, 30 kgf, 45 kgf. The indenter of either test shall be of spheroconical or spherical configuration The standard indenters are the diamond spheroconical and tungsten carbide ball indenters' 1/16, 1/8, 1/4, 1/2 inch in diameter. Annex 3 or A3. STANDARDIZATION OF ROCKWELL INDENTERS, covers the requirements of indenters to be used. The dust, dirt, grease and scale shall not be allowed to accumulate on the indenter as this will affect the test. Anvils used for indention’s must be suitable for specimen. Cylindrical pieces shall be tested with a V-grooved anvil Flat pieces shall be tested on a flat anvil, whose plane is perpendicular to the axis of the indenter. The anvils shall be clean and smooth and free from pits, scratches, dust, dirt and grease. The anvil and indenter shall be set properly by running two tests not used in calculations.

The test specimens shall be clean and prepared in a way that alteration of the surface hardness is minimized. Flat specimens' surfaces should be flat and parallel to indenter and anvil. The thickness of the test piece or of the layer under test should be as dictated in Table 7, 8, 9, and 10 of ASTM E18. The general rule, is the thickness should be 10 times the depth of the indenter. For tests on convex cylindrical surfaces the corrections given in Tables 11, 12, 13, and 14 of ASTM E18 shall be applied.

Place the specimen on the proper anvil and bring the indenter in contact with specimen until the machine engages the minor load. This indicates machine is ready for reading and will give automatic readout. There should be a minimum 3 readings per sample and 4 readings for bolt testing. Each reading should be a distance of three times the diameter of the indenter apart. Take an average of the readings for the final result. If technician believes that a reading is not representative of material an additional 3 readings can be used to replace the one.

Before each test using a different scale, start of a day, or change of indenter the machine will be calibrated using NIST traceable hardness blocks. This calibration will be logged and recorded using hardness block limits with an average of three readings for each test block.   After testing the final report will include Rockwell hardness number, scale used, and readings to nearest the whole number by rounding in accordance with ASTM E29.


Q4: Qual é a aplicação do teste de Dureza Rockwell e Superficial?


No ensaio de Rockwell, a Dureza é determinada medindo a profundidade comparativa de duas indentações cuidadosamente controladas, UMA sobreposta à outra.


First a Minor Load (one of a lesser force) is applied to a steel ball or sphere—conical diamond perpetrator. Then, while the Minor Load is still being applied, a Major Load (one of greater force) is applied at a precisely controlled rate. The Major Load is removed and the hardness determination is displayed.


The hardness determination obtained represents the additional depth to which the Major Load has indented the test specimen beyond the initial indentation of the application of the Minor Load. The displayed indication is proportionally inverse, e.g. the higher the displayed determination of hardness, the shallower the indentations, therefore the harder the material.


In the regular (R) Rockwell scale, the Minor Load is is 10 kgf and the Major Load may be 60, 100, or 150 kgf. In the superficial scale (S), the Minor Load is 3 kgf and the Major Load may be 15, 30, or 45 kgf.


To ensure accuracy and consistency, the Major Load is under precise control and the Penetrate are manufactured to specific tolerances. Each point of hardness on the regular (R) scale is 0.00008 inch and 0.00004 inch on the superficial (S) scale, making the need for precise control of the applied forces and precision manufacture of the Penetrate readily apparent.


Escalas Superficiais Rockwell


PEDIDOS REGULAMENTARES DE ROCKwell (R)
Símbolo Da Escala Penetrate
Maior (Menor)Carga Aplicação típica
Sim. Diamante de cone 60 KGF (10 kgf) «Carbonetos cimentados » aço Fino » aço endurecido EM minúsculas
B Bola 1/16 100 KGF (10 kgf) «Ligas de Cooper», «aço macio», «ligas de alumínio», «ferro maleável»
C Diamante de cone 150 KGF (10 kgf) Aço · ferro fundido Duro · ferro maleável perlítico · titânio · aço endurecido de Fundo
D Diamante de cone 100 KGF (10 kgf) «Aço fino», «aço endurecido» ferro maleável perlítico
E. Bola 1/8 100 KGF (10 kgf) Ferro fundido, ligas de alumínio, ligas de magnésio, METAIS metálicos
F Bola 1/16 60 KGF (10 kgf) « ligas de Cobre anizadas » finas Chapas metálicas
G. Bola 1/16 150 KGF (10 kgf) «Órfãos de bronze· berílio · ferro maleável »(G92+) prejudicarão o penetrador)
H Bola 1/8 60 KGF (10 kgf) «zinco· Chumbo » alumínio
K. Bola 1/8 150 KGF (10 kgf) · Metais Portadores · matérias finas · matérias plásticas · relativamente Macias · matérias finas » (refiro-me à ASTM D7851)Use a Bola Mais Pequena e a Mais Alta que não produza efeitos « bigornas ».
L Bola 1/4 60 KGF (10 kgf)
M Bola 1/4 100 KGF (10 kgf)
P Bola 1/4 150 KGF (10 kgf)
R Bola 1/2 60 KGF (10 kgf)
Sim. Bola 1/2 100 KGF (10 kgf)
V Bola 1/2 150 KGF (10 kgf)

ASTM D785 (Vol. 08.01) Método de ensaio padrão para a Dureza do Rockwell DOS plásticos e materiais de Insulação Elétrica


Escalas Superficiais Rockwell


PEDIDOS DE PESSOAL SUPERFICIAIS
Símbolo Da Escala Penetrate
Maior (Menor)Carga Aplicação típica
15N. Diamante de cone 15 KGF (3 kgf) A escala superficial é ideal para testar materiais que não têm largura ou espessura suficientes para Serem testados Na Escala de Dureza de Pedras Regular (R),Estas são tipicamente: · Chapas Muito finas · strip metal · FIO · pequenas rondas · nitride steel · ligeiramente carburado · aço fortemente cianideado · Placa de estanho · outras amostras Ou materiais igualmente configurados.
30N. Diamante de cone 30 KGF (3 kgf)
45N. Diamante de cone 45 KGF (3 kgf)
15T. Bola 1/16 15 KGF (3 kgf)
30T. Bola 1/16 30 KGF (3 kgf)
45T. Bola 1/16 45 KGF (3 kgf)
15W. Bola 1/8 15 KGF (3 kgf)
30W. Bola 1/8 30 KGF (3 kgf)
45W. Bola 1/8 45 KGF (3 kgf)
15X. Bola 1/4 15 KGF (3 kgf)
30X. Bola 1/4 30 KGF (3 kgf)
45X. Bola 1/4 45 KGF (3 kgf)
15Y. Bola 1/2 15 KGF (3 kgf)
30Y. Bola 1/2 30 KGF (3 kgf)
45Y. Bola 1/2 45 KGF (3 kgf)

Escalas de Carbidos Rockwell


Testes de escala C (carboneto) são usados para testar carbonetos cimentados Na Escala Rockwell A, ONDE são necessárias tolerâncias de $1000.20 de um Ponto de Dureza Rockwell.Utiliza-se um penetrador de travões especialmente seleccionado "A" para medir a Dureza DOS carbonetos cimentados de acordo com o ASTM B 294 e com a Associação de Produtores de Carbide Cemented (CCPA).


In addition to the 60 kgf Major Load required for carbide A Scale testing, the Scale C testers also include 100 and 150 kgf capabilities.