CN112244615A

CN112244615A - Non-carcinogenic stainless frying pan

Info

Publication number: CN112244615A
Application number: CN201910659998.9A
Authority: CN
Inventors: 马兆瑞; 马丹萌
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-07-22
Filing date: 2019-07-22
Publication date: 2021-01-22

Abstract

Belongs to a non-carcinogenic stainless frying pan of a Chinese cooking segment-shaped frying pan, and has the principle of non-carcinogenicity, non-sensitization and non-rust property and a manufacturing method thereof: the main body piece of the small-caliber frying pan with the diameter of 26-38 cm is manufactured by adopting a cold-rolled low-carbon steel plate which does not contain carcinogenic agents of chromium, nickel, chromium metal, nickel metal and nickel alloy in a mould pressing mode; the large-diameter frying pan main body part of 56-108 cm is cast by gray cast iron and nodular cast iron. And then nitriding or nitrocarburizing process is carried out on the main body part of the frying pan formed by die pressing or casting, so that a nitriding layer with 0.20-0.42 mm thickness and strong abrasion resistance and corrosion resistance is generated on the surface of the frying pan. Even if particles which are frequently collided and ground by the metal frying shovel in the frying process of the frying pan enter dishes and eat into the digestive system of a human body, the particles are iron, trace nitrogen and carbon which are harmless to the human body. Because the thermal conductivity is lower than that of a nitriding layer of steel, the oil smoke of initial frying can be reduced; and has a tendency to "stick-out" and is easy to clean.

Description

Non-carcinogenic stainless frying pan

(I) technical field

Metalworking, oncology epidemiology, oncology prevention, cancer primary prevention, chemical heat treatment nitriding or nitrocarburizing process, applied to kitchen utensils, Chinese style woks.

(II) background of the invention

By metallic definition, the concept of "stainless" means that it does not rust in air, such as stainless steel.

The frying pan used for the food cooking of Chinese nationality is different from the pan used for western food. The Chinese cooking mode is to cook dishes in a spherical-segment-shaped metal pot, and in order to ensure that the cooked dishes are uniformly heated in the pot, a cooking turner is required to continuously turn the dishes from the bottom to the upper part in the pot. The frying shovel used by the Chinese predecessors in the two thousand years is basically commonly called an iron shovel (also commonly called a black iron shovel because of rusting) and the used frying pan is commonly called an iron pan (also commonly called a black iron pan because of rusting). The so-called "iron" is cast iron or steel plate. The commonly known iron plate belongs to a carbon steel plate according to the metal concept, wherein iron refers to an alloy consisting of elemental iron (Fe) and trace carbon (C); cast iron, which is an iron-carbon alloy, has a higher carbon content than steel. It is well known that ordinary steel is easily rusted in the atmosphere in which we live. This corrosion is electrochemical corrosion. The rust spots of the iron oxide (ferric oxide) formed on the surface of the common carbon steel are continuously enlarged, and the corrosion speed is high. The occurrence of electrochemical corrosion is a process which can not be overcome by ordinary steel exposed in air. In addition, the rust on the frying pan is mixed into the dish, which not only damages the taste of the dish, but also influences the aesthetic property of the surface color of the frying pan. British metallurgy experts sharehi Braille (Harry Brearley) in the first 20 th century discovered that when more than 12% chromium was added to the steel, the steel did not rust in air, and thus produced stainless steel. Ferritic stainless steel, pearlitic stainless steel, and martensitic stainless steel containing only chromium are commonly referred to as "stainless iron" because of their magnetic properties. The austenitic stainless steel which is most widely applied in the world and contains 18-20% of chromium and 9-10.5% of nickel has no magnetism. The stainless steel and alloy steel made of chromium and nickel as alloy components in different proportions can present high strength, heat resistance, acid resistance, alkali resistance, atmospheric corrosion resistance, good comprehensive mechanical properties and the like. Stainless steel has a wide and important application in almost all fields of industry. Chromium and nickel are therefore called "industrial bones". China is a country lacking in the mineral resources of chromium and nickel. Since the 80 th century in China, a large amount of chrome-nickel mineral products or stainless steel materials can be imported overseas, and therefore white, bright and beautiful stainless steel frying pans appear in the Chinese market. But also comprises stainless steel frying pans manufactured by a plurality of famous kitchen ware manufacturers in Germany and China. To provide evidence for the prior art of the present patent application, the applicant took photographs of some stainless steel woks sold on the market. The labels of all stainless steel woks in the Chinese market are marked that the materials are stainless steel so as to dazzle the good selection of the materials. For example, there are references to "304", "18-10", "food grade stainless steel", "medical stainless steel", "stainless steel conforming to the Chinese national standard GB 9684-2011", etc., in order for the user to believe its safety.

U.S. grade "304" stainless steel, the chinese grade "chromium 18 nickel 9" stainless steel, is the most widely used austenitic stainless steel grade worldwide.

However, chromium metal, nickel element, nickel metal, and nickel alloy, which constitute austenitic stainless steel, are collectively referred to as nickel-chromium. Nickel is also the allergen of nickel allergic dermatitis, and medical statistical data show that five people are allergic to nickel.

The Chinese national standard GB9684-2011 which is in line with the European Union standard and the Germany standard is a standard established for stainless steel in the food industry. It is defined as follows: the amount of nickel and chromium migrating into the acetic acid solution of the experimental medium due to the thermal movement of molecules is limited under a static state. These standards do not completely restrict the migration amount of nickel and chromium which are dynamically and frequently collided and worn away between a stainless steel frying shovel and a frying pan in Chinese cooking and frying operations.

The unique point of Chinese cooking is that a frying shovel and a frying pan are used for frying during the frying operation. Frequent collision type abrasion between the frying shovel and the metal of the frying pan is inevitable. The nickel-chromium as heavy metal has the physical and chemical characteristics of super heat resistance, acid resistance and alkali resistance.

Even if the frying pan is made of stainless steel which meets European Union standards, German standards and Chinese standards GB9684-2011, the situation that nickel and chromium which are frequently abraded by collision between a frying shovel and metal of the frying pan are not mixed into dishes and are eaten in vivo is avoided.

Note the following figure at page 3 of the documentation: a kitchen ware manufacturer in Germany, which is famous all over the world, has a die pressing 18/10 character at the center of the outer surface of the bottom of a stainless steel frying pan produced in China so as to dazzle the stainless steel with excellent material selection. "18/10" means a generic name for stainless steel containing 18% chromium and 10% nickel, commonly known as 18-10%.

The nickel chromium belongs to the scientific basis of carcinogenic agents

1, Shanghai's first college of medicine "practical internal sciences" editorial Committee to write "practical internal sciences" (published by the people's health publishing house, 7 th edition of 5 months 1981), on page 1239 of the book is written: "physicochemical carcinogenic factor: currently, the known carcinogenic factors include tobacco heating products, chromium, chromate, and nickel. "

2, the European Association 1994 issues a Standard "Nickel Release Instructions" (94/27/EC): products which are in long-term contact with human bodies, such as earrings, necklaces, watch chains, watchcases, tooth sockets and the like, have the nickel content of less than 0.05 percent. All hospitals in China nowadays and all people who do heart operation mounting brackets know to mount the titanium alloy bracket. The essence of the titanium alloy stent is as follows: the standard for its implementation does not allow the use of chrome-nickel stainless steel for the fabrication of cardiovascular stents.

Details of chromium and nickel in nine hundred of carcinogens published by the International Agency for Research on Cancer (IARC) affiliated to the World Health Organization (WHO) on 10 months and 22 days 2010 are as follows:

in this table, "carcinogens: chromium, metals "(written" Chromium, metallic "for english master)," carcinogens: nickel, metals and alloys "(the English edition is correspondingly written" Nickel, metallic and alloys "). That is, not only chromium and nickel are carcinogenic agents, but also chromium metal, nickel metal, and nickel-containing alloys are carcinogenic agents.

4, the first department of China, "prevention of oncology", published by the national institutes of medicine, national health publisher 2015, international standard book number ISBN 978-7-117-. Main weaving: 110 editors of Zhao Ping professor, Wang Long Longde courtyard of China preventive medicine society, and the like. Pages 322 and 329, the carcinogens chromium, chromium metal, nickel metal and nickel alloy are cited in the declaration of the international cancer research institute.

5, the most widely used stainless steel all over the world is austenitic stainless steel with 18-20% of chromium content and 9-10.5% of nickel content. The steel grade is expressed in different countries as: china 0 Cr18Ni9 or 06 Cr19Ni 10; us304 or S30400; uk 304S 15; japanese SUS 304; france Z6CN18.09; germany, European Committee for standardization (CEN: EN10088-1-2005) and International organization for standardization X5CrNi 18-9.

6, an austenitic stainless steel containing 18 to 20% of chromium and 9 to 10.5% of nickel regardless of countries.

Unique characteristics of using frying pan for cooking operation

With a complete chain of evidence.

1, during the frying operation, when a metal frying shovel is used for frying, frequent collision type abrasion between the metal frying shovel and a frying pan is inevitable. If a stainless steel frying pan is used, the carcinogenic chromium metal, nickel metal and nickel alloy particles which are abraded by collision enter dishes, and are inevitably eaten into a digestive system by family members, and the stainless steel frying pan is initially applied by mymeri 2009, 8/20 and is granted patent of a low-carbon steel integral bluing turner without stainless steel and necessarily containing chromium and nickel on 2010, 10/20 (patent number ZL 200920171113.2). As the frying pan is used for frying, frequent collision type abrasion between the frying shovel and the frying pan metal is inevitably generated, and the abraded nickel-chromium particles are inevitably eaten into the bodies by family members.

2, Ma Merrill and Ma Dan sprout application for Chinese patent in 2017. ZL201720275748.1 'nitrogenized low carbon steel spatula' was granted in 2018, 5 months and 4 days.

In 8 months 3,2018, The society of cancer prevention (CACA), International Union of cancer prevention (UICC), and society of cancer prevention In The United states, recorded paper 909544, namely Magnety, Madanese, The discovery of The stationary-free spraying map of Cr-Ni stationary step In The center of The kitchen of The cooking with Chinese chips to form carcinogenic channels, and popular science. See "invent special forBook of Requests

Add file list other documents for certification page 5. The article [ introduction ] is as follows at line 26:

nowadays, almost all metal cooking turners sold in the China market are made of chrome-nickel stainless steel. The foundation of legal evidence in this paper is two main: one, carcinogens derived from the international agency for research on cancer and identified by "preventive oncology": chromium, chromium metal, nickel metal, and nickel alloys. Second, the authors of the present text describe in patent ZL200920171113.2 granted in 2010 and patent ZL201720275748.1 granted in 2018: in traditional Chinese cooking, a Chinese cooking turner and a pan with a spherical bottom must be used. Metal collision type abrasion between the slice and the pan inevitably occurs.

The discussion herein presents: chinese cooking is different from western cuisine 1. In traditional Chinese cooking, a Chinese spatula and a pan with a bulbous bottom are used. Six factors which are integrated into a whole by six parts of a solid passage are necessarily formed when the chromium-nickel stainless steel turner is used for frying dishes, and the six factors form a whole body of a complete evidence chain; 2, since the physiological characteristics of the rectal folds and the transverse folds are the fold state, the method provides good physical conditions for the heavy metal chromium-nickel alloy solid micron-sized microsomes to be stored in the rectal folds and the transverse folds. The authors foresee that this could be a substantial cause for the 4.2% annual growth rate in colorectal cancer in china over thirty years. 3, the nickel alloy with high content of chromium and nickel has super stability to high temperature, acid and alkali. The carcinogenic agents of chromium metal, nickel metal and nickel alloy eaten in the body cannot be oxidized or decomposed in the body. Thereby negating the epidemic saying that "colorectal cancer has a genetic element"; 5, the molecular carcinogen chromium nickel with angstrom-sized particles can enter other organs of the human body by virtue of a digestive system and a blood circulation system, thereby bringing various cancer accidents to human beings; 6, the reasons, basis and significance of the China national Standard administration Committee, the China national health Committee and the national food safety Risk assessment center to revise the current national Standard GB9684 + 2011.

In the 5 th month 4,2019, the Megger of Marble and Madaneng treatise on the 2019 Congress of Chinese oncology Focus academy in China, recorded in the Megger of Madanese, the Carcinogenesis from Ni-Cr category accumulation in human body forming the greatest carcinogenic risk to human body for the human body, as "Excellent Lexue article", compiled in the Association's literature, the article "Association". See patent application for invention

Add file list other documents for certification page 6. The dame reception conference invites participation in the conference held at the hotel of wanda warfarin, zheng. In the treatise book 59, the only article in the fields of "tumor epidemiology" and "primary cancer prevention" is "outstanding symptoms". Synthesis of nickel-chromium-derived air channels (nickel-chromium-derived mines and their smelting), liquid channels (inevitably produced during the production of beer, beverages, dairy products, pharmaceuticals and health products), solid microsome channels (inevitably produced during the frying of dishes by stainless steel shovels or stainless steel woks, ground coffee beans, ground oats, pressed and dried), and tail gas channels (inevitably produced in gasoline, diesel oil, kerosene and refinery gas due to petroleum refining). The latter two pathways, solid microsome pathway, exhaust pathway, were discovered by marmeri, madeng. In addition, in view of the theory that the carcinogenic theory of nickel and chromium accumulated in human bodies is more causal than the carcinogenic theory of immunity reduction and is directly carcinogenic; the theory can reasonably explain the worldwide cancer morbidity phenomenon and law: the higher the human civilization development index, the higher the incidence of cancer; the incidence of cancer increases with age. The paper explains the physical condition of nickel chromium species to form a risk for colorectal cancer. The article describes nanoscale molecular state or ionic state chromium and nickel carcinogens. The 0.2486 nanometer nickel molecular carcinogenic agent with the diameter of one eighth of influenza virus has super heat resistance, acid resistance and alkali resistance. With the possibility of infiltration into the blood circulation system. It has carcinogenic risk to many other organs of the human body, including the cleanest brain.

The marmeri and madeng paper "excellent character" from the "2019 chinese oncology focus academic congress paper compilation" (abstract) is as follows 31:

1, the original discovery of the authors about the formation of a nickel-chromium solid pathway by frying with a stainless steel turner has been popular with government department of western city in Beijing and the university of 2018 Chinese Oncology. The emphasis herein is on the fluid pathways of nickel chromium species (chromium, chromium metal, nickel metal, nickel alloys) that are more harmful to humans, and the main source of recent carcinogenesis in humans is the cumulative theory of nickel chromium species in the body. 2, the first 20 countries with the highest incidence of cancer worldwide are the most economically developed europe, america and korea. Many carcinogenic theories prevail in the contemporary medical community, such as: the higher the human progression index, the higher the incidence of cancer; the incidence of cancer increases with the decline of immunity with age; lifestyle changes to cancer; high fat and high protein intake to cause carcinogenesis; the more the age, the more the number of cell divisions causes more chance of gene mutation and causes cancer. These theories do not have causal properties of direct carcinogenesis; 3, all equipment, containers, pipelines, valves, crushers, mixers, heat exchangers and homogenizers for processing food, drinks, dairy products, medicines and health care products all over the world are made of stainless steel; 4, the most widely used stainless steel contains 18 percent of chromium and 9 to 10.5 percent of nickel. And the nickel chromium is a heavy metal carcinogen confirmed by the international cancer research institute and prevention oncology, and has super-strong stability to high temperature, acid and alkali. Will not oxidize or decompose in vivo, but will only accumulate more; 5, according to the law of molecular thermal motion, in the process of industrially processing food, drinks, medicines and health-care products, nickel and chromium in stainless steel inevitably migrate into a processed medium in three ways, and the migration amount is in direct proportion to temperature and acidity; 6, the more economically developed countries, the more food, drink, and medicine are eaten by people in factory processing, and particularly, the most amount of nickel and chromium is eaten through a nickel and chromium liquid passage. Therefore, the actual phenomenon that the incidence rate of cancer is higher as the human development index is higher becomes evidence of the theory that nickel chromium accumulates carcinogenesis in human body. This theory has direct oncogenic causal properties; cancer data in developed and under-developed regions, as well as international, european union, and chinese standards for the restriction of nickel-chromium species, published by WHO, are numerous evidences of the direct causal properties of nickel-chromium species as a cumulative carcinogenic theory; 8, the molecular or ionic carcinogen of nickel-chromium with angstrom size can permeate into other organs of human body by means of digestive system and blood circulation system, thus bringing about various cancer accidents to human beings, including the cleanest brain; 9, reasonable interpretation of IARC release "global epidemiological data of tumor prevalence 2012" on colorectal cancer distribution. The incidence of colon cancer is derived from how much of the processed beverage is taken in the factory. The highest incidence of cancer in developed countries and regions is associated with the fluid pathway of nickel and chromium; 10, the theory that nickel and chromium accumulate carcinogenesis in human bodies has more causal property of direct carcinogenesis than the carcinogenesis theory that the immunity is reduced; 11, the improvement of human development index, the popularization of stainless steel in the food industry and the pharmaceutical industry, and the increase of cancer incidence rate are coupled. 12, illustrating the presence of a nickel chromium exhaust gas pathway.

Some statistics of the present state of cancer in China

The Chinese media is published in 2017, 2, 4 and 4 in the world cancer day, and the tumor incidence number in China 2015 is 430 thousands of people. Among them, the number of patients suffering from digestive system cancer is nearly half.

The current state of China is that about six thousand new digestive system cancers, including one thousand and hundreds of colorectal and anal cancers, occur daily. Furthermore, the dregs containing carcinogens move from the colon to the rectum and are excreted further down the exposure to carcinogenic metals is higher, i.e. carcinogenic metals in the dregs are more threatening the rectum than the colon. Thus forming a short length rectum with twice as many incidence as a colon cancer as a longer length colon. This conclusion was demonstrated in chinese clinical case statistics. Clinicians also find that there are people in the same family who suffer from colorectal cancer. Thus, both the elderly and young members of the same family who use the inconel pan have a possibility of developing colorectal cancer-thereby precluding colorectal cancer from being inherited.

In millions of years of human evolution, Chinese never like the current use of austenitic stainless steel stir-frying pans and woks to eat such huge amount of carcinogens of chromium, nickel, chromium metal, nickel metal and nickel alloy. Since nickel-chromium compounds have superior heat resistance, acid resistance and alkali resistance, they are never oxidized or decomposed in vivo. The more accumulated the more. The more nickel chromium species accumulate in the body with age, the greater the risk of carcinogenesis with age. The national cancer center promulgates that the incidence rate of 40-80 year-old cancer is the best to confirm.

Stainless pan for searching non-carcinogenic

The keywords "wok", "non-carcinogenic wok", "nitrogenated wok" and "nitrocarburizing wok" are input at the patent database website www.patentics.com to search for chinese patents. The contents of the abstract description after clicking on the appearing patent name are all irrelevant to the present patent application. The contents of the european patent, the united states patent and the WO patent (international organization of PCT patent cooperation treaty) are searched for by continuously inputting keywords such as cooking pan in Chinese style frying pan, frying pan in Chinese style frying pan, nitriding pan, nitrided frying pan, nitrocarburing pan and non-carcinogenic frying pan into the database website, and are irrelevant to the present patent application.

Disclosure of the invention

In order to realize the non-carcinogenic and non-rusty technology of the frying pan in the frying operation, the overall technical scheme adopted by the invention is as follows:

firstly, a cold-rolled low-carbon steel plate with strictly controlled contents of chromium and nickel impurities (nickel should be less than 0.05%) is selected to manufacture the frying pan main body piece. A frying pan with the diameter of 26-38 cm for household and restaurant use is preferably formed by die pressing of a cold-rolled steel plate. And removing burrs and grinding edges. If high nitriding quality is pursued, the main body part of the frying pan can be subjected to sand blasting treatment by using alumina powder before nitriding. Then the frying pan main body piece is processed by chemical heat treatment nitridation (nitriding) or nitrocarburizing process.

Secondly, cast iron with strictly controlled contents of chromium and nickel impurities (both less than 0.05%) is used for casting the main body piece of the frying pan. The spherical frying pan is manufactured by adopting a casting process according to the actual use and size (when the diameter of the frying pan for families and restaurants is 32-38 cm; and the diameter of the frying pan for large dining halls of the group is 56-108 cm). And removing burrs and grinding edges. Before nitriding, the main body part of the frying pan needs to be subjected to sand blasting treatment by using alumina powder. Then the frying pan main body piece is processed by chemical heat treatment nitridation (nitriding) or nitrocarburizing process.

Thirdly, the core technology of the non-carcinogenic stainless frying pan of the invention is the chemical heat treatment of the frying pan main body: nitriding (nitriding) or nitrocarburizing (nitrocarburizing). The nitriding purpose is to form a thin compound layer and a diffusion layer on the surface of the frying pan, control the selected specific nitriding process to have good nitriding temperature, nitriding heat preservation time and other process parameters, ensure that the working surface of the frying pan main body part generates a nitriding surface layer with the thickness of 0.20-0.42 mm, high hardness, strong wear resistance and excellent corrosion resistance, and control the total thickness of the diffusion layer not to exceed 0.42 mm.

Nitriding media are mainly ammonia (NH)₃). Nitriding of the main body part of the frying pan is generally carried out in four nitriding media (ammonia, ammonia and hydrogen, ammonia and nitrogen, and mixed gas of ammonia and decomposed ammonia, namely ammonia, hydrogen and nitrogen after ammonia decomposition). Generally, nitriding is carried out at a temperature of 500 to 600 ℃. The main component of the low-carbon steel wok main body part is iron (Fe), and nitrogen (N) permeates into the appearance of the low-carbon steel (or cast iron), so that the chemical components and the structural organization state of the surface of the low-carbon steel (or cast iron) wok main body part are changed by a nitrided layer after nitriding, namely the nitrided layer on the surface of the wok main body part has five phase regions represented by Greek letters: alpha phase, gamma' phase, epsilon phase and zeta phase.

The alpha phase is alpha-Fe with ferromagnetism, and the toughness is good; the gamma phase is an interstitial solid solution of nitrogen in gamma-Fe; the ferromagnetic phase gamma' being a compound of iron and carbon Fe₄N, the toughness is good; the epsilon phase of ferromagnetic phase is a compound with variable iron and carbon components, the component being Fe₂N、Fe₃And N has strong abrasion resistance and excellent corrosion resistance, and high nitrogen has better corrosion resistance.

Five phases are generated in the nitriding layer, so that the low-carbon steel (or cast iron) frying pan main body piece obtains strong abrasion resistance and corrosion resistance. The strong corrosion resistance ensures that the stainless pan without carcinogenicity has the function of rust prevention; the strong abrasion resistance prolongs the service life of the product with the function of rust prevention.

(IV) advantageous effects

Firstly, the specification explains the principle and the manufacturing method that the Chinese cooking-used segment-shaped frying pan, namely the non-carcinogenic stainless frying pan, has the non-carcinogenicity and the non-rust property.

Secondly, compared with stainless steel frying pan, the utility model has no carcinogenicity and sensitization

After the product of the invention is implemented, the low-carbon steel (or cast iron) of the frying pan main body piece and the elements of the nitriding layer are iron, carbon and nitrogen. Among carcinogens reported by the international agency for research on cancer (IARC) WHO is affiliated with the World Health Organization (WHO), iron, carbon, and nitrogen are absent. The product of the frying pan does not contain chromium, nickel, chromium metal, nickel metal and nickel alloy carcinogenic agent which are necessarily contained in stainless steel. The product of this frying pan is even if by the frequent collision grinding of metal spatula and get into the human body and eat into the particle body of digestive system in the operation of cooking, is the iron and the trace amount nitrogen, carbon element harmless to the human body. Compared with the stainless steel frying pan in the prior art, the stainless steel frying pan has the advantages of no carcinogenicity and no sensitization.

The most important beneficial effects of the product of the invention are that the product has no carcinogenicity, no sensitization and no rust. The name of the stainless wok without carcinogenicity conforms to the actual name. The use of the stainless frying pan product without carcinogenicity can turn the situation that the stainless frying pan is used for frying dishes to harm the health and the life of human beings.

Thirdly, the nitriding layer of the stainless pan has good high-temperature corrosion resistance and wear resistance

The operating temperature of the single-acting slide valve and the double-acting slide valve of one of the key equipment of the catalytic cracking unit of the oil refinery is over 500 ℃. The valve plate track is nitrided. The bearing frame is also nitrided. The nitriding layer with the thickness of 0.20-0.42 mm of the stainless frying pan has good corrosion resistance and wear resistance at high temperature. The nitrided layer of the stainless wok is sufficient to accommodate cooking temperatures. From the carburization of tank grip-pad alright understand that the nitriding layer has good corrosion resistance and the visual effect of wearability. Since nitrogen is a more inert element than carbon.

Fourthly, the tendency of less oil smoke and anti-sticking pan during the initial frying of the dish

Because the heat conductivity of the nitriding layer of the stainless non-carcinogenic frying pan is far less than that of the iron and steel parent body, the evaporation of oil smoke can be reduced in the initial frying process of the frying operation. The nitrided layer reduces sticking to cooking foods in contact therewith, has a tendency to "stick-out" and is therefore also easy to clean.

Fifth, the world health organization's international agency for cancer research is well-documented by the knicker friedel-crafts (Dr Christopher Wild): to solve the problem of the frightened increase of the global cancer burden, a lot of things are needed to be done, and the prevention plays a key role. "(the new setting high fat areas from the areas to the areas of the cancer butyl globalley, and the fat preservation has a key roll to the plant.) the subject of this patent application is" first degree prevention of cancer ". The "refusal of cancer to prevent seriously", especially the primary prevention, should be a permanent consensus among humans throughout the world.

The applicant thus filed the patent of the invention, namely 'stainless pan without carcinogenicity'.

(V) detailed description of the preferred embodiments

First, the main body of the frying pan is selected

The main body piece of the non-carcinogenic stainless frying pan is made of the following materials: preferred cold rolled low carbon steel sheets are, for example: selecting carbon structural steel Q195, Q215B, Q215BF, Q215C or Q235B, Q235C and the like according to Chinese national standard GB/T700; selecting high-quality carbon structural steel No. 08, 08F, 10F, 15F and 20 according to Chinese national standard GB/T699-2015. The nickel content and the chromium content of impurities of the materials used for the main frying pan body piece are strictly controlled, and the nickel content after sampling inspection is less than 0.05 percent. According to the caliber (38, 37, 36, 35, 34, 33, 32, 30, 28 and 26 cm) of the frying pan, a cold-rolled steel plate with the thickness of 4.0-2.5 mm is selected.

The corrosion resistance of the gray cast iron is obviously better than that of the steel plate. Therefore, the traditional iron pan in China is usually manufactured by a casting process of gray cast iron. Because this scheme is going on nitriding treatment. Therefore, the frying pan with large caliber (56, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 108 cm) is selected from gray cast iron and nodular cast iron. For example, gray cast iron HT-200, HT-250, HT-300 and HT-350 are selected according to GB9439-1988 (GB/T9439-2009); or selecting nodular cast iron QT-350, QT-400 and QT-450 according to GB1348-1988 (GB/T1348-2009).

Secondly, preparing the frying pan main body part before blanking and nitriding

If the cold-rolled steel plate is used for compression molding to manufacture the main body piece of the frying pan, the pressure is not less than 4000 tons of hydraulic press. No matter the cold-rolled steel plate is adopted for compression molding or the gray cast iron is adopted for casting molding, the spherical segment shaped frying pan main body piece is formed. After the molding, the deburring, edge polishing and shaping are required. For the casting pan main body part and the mould pressing pan main body part with high quality requirement, before nitriding, the alumina powder is used for carrying out sand blasting treatment on the pan main body part. And then nitriding treatment is carried out. Ultrasonic water washing and drying. And (5) intermediate quality inspection.

Then nitriding process treatment is carried out on the clean wok main body piece. The aim is to form a thin compound layer and a diffusion layer on the surface of a frying pan main body piece, so that a nitriding layer with the thickness of 0.2-0.42 mm, high hardness, strong abrasion resistance and excellent corrosion resistance is generated on the steel surface of the frying pan.

Nitriding of main body part of frying pan

Specifically, the nitriding technology is selected according to the requirements on the grade positioning of the frying pan product, the depth of a nitriding layer, abrasion resistance, corrosion resistance and the like, and gas nitriding, ion nitriding, gas nitrocarburizing or liquid (salt bath) nitrocarburizing is selected.

The nitriding holding time depends on the nitriding temperature and the depth of the nitriding layer. The tendency of the carburized layer to be crisp can occur due to the overlong nitriding heat preservation time. No matter which technique is adopted to carry out nitriding on the main body part of the frying pan, the heat preservation time is controlled to be 60 minutes to 120 minutes.

1, gas nitriding: namely, the frying pan main body part carries out nitriding treatment on the workpiece in a well type nitriding furnace containing ammonia gas. The ammonia gas comes from a liquid ammonia bottle. The method has the advantages of simple equipment, low investment, simple and convenient operation, stable quality of the nitrided piece and the like, but the process takes longer time and the diffusion layer is thinner. According to the required grade of the product, the main body part of the frying pan is treated by adopting the conventional nitriding process, the corrosion-resistant nitriding process or the short-time nitriding process.

2, ion nitriding: the operation is generally carried out in an ion nitriding furnace at a rated temperature of 650 ℃ according to JB/T6956-2007 standard. Has the advantages of high nitriding speed, low energy consumption, low ammonia consumption, good comprehensive performance of a nitriding layer and the like. The nitriding temperature is 550-570 ℃, the total thickness of the nitriding layer is 0.20-0.42 mm, and the Vickers Hardness (HV) of the surface of the nitriding layer is not lower than 250. The nitrided layer has the structure of FeN, Fe2N, Fe3N and Fe4N from the outside to the inside in sequence. It is noted that the surface color of the ion-nitrided piece is silver gray or dark gray.

3, gas nitrocarburizing: in a gas nitrocarburizing furnace, the operation is carried out according to the national standard GB/T22560-2008. Has the advantages of short operation time, lower operation temperature, good abrasion resistance and corrosion resistance of the product and the like. The general gas nitrocarburizing temperature is 520-570 ℃, the time is 2 hours, and the total diffusion layer thickness of the compound layer and the diffusion layer can reach more than 0.3 mm. The performance of the obtained product is basically consistent with that of salt bath nitrocarburizing.

4, liquid (salt bath) nitrocarburizing: the process is characterized in that: under the economic and simple advantages of high heating speed, short time and low heating temperature, the compactness of the nitrocarburizing layer can be ensured, thereby realizing the corrosion resistance and the abrasion resistance of the working surface of the main body piece of the frying pan. However, in the old process, cyanide sodium cyanide and potassium cyanide are used as raw materials for nitrocarburizing salt bath, and both are highly toxic substances. Although the old process technology has many advantages, it is not recommended to use NaCN and KCN as raw materials for liquid nitrocarburizing because of the generation of toxic substances to be emitted into the air. The formula of the raw material medium (mass percentage) for nitrocarburizing of the lower table salt bath is recommended to be used at the temperature of 550-570 ℃:

chemical reaction in nitrocarburizing process

(NH₂)₂CO+Na₂CO₃＝NaCNO+NH₃+CO₂

Although the five raw materials are non-toxic, the reaction of urea with carbonate to form cyanate is toxic. Although the overall toxicity is far less than that of cyanate, care must be taken to prevent poisoning.

5, the final step of nitriding process treatment of the frying pan main body part comprises cleaning with hot trisodium phosphate solution, cleaning with hot water and quality inspection.

6, although the 21 st century, the important parameter of the nitriding process, namely the nitrogen potential (the ratio of the partial pressure of ammonia in nitrogen potential furnace gas to the partial pressure of nitrogen to the power of 1.5), realizes computer display and control so as to ensure the integral quality of nitriding. However, in order to ensure the quality of the final product of the stainless wok without carcinogenicity, no matter what nitriding process is adopted, the main body part of the wok after all nitriding steps are subjected to sampling inspection. The following criteria are important: the surface hardness (representing the wear resistance) and hardness gradient of the nitrided layer, the depth of the nitrided layer, the thickness and structure of the compound layer, and the brittleness of the nitrided layer. The surface of the nitriding layer must not have cracks.

7, the handle of the frying pan can be prepared according to the traditional wooden single handle, metal single handle or double-ear metal handle.

Claims

1. The claimed claim of non-carcinogenic stainless wok is the principle and the making method of the nodular shaped wok used for Chinese style cooking dish, which has non-carcinogenic, non-sensitizing and non-rusty properties: the non-carcinogenic stainless frying pan is characterized in that a main body part of a frying pan with a small diameter of 26-38 cm, which is used in families and restaurants, is manufactured by adopting a cold-rolled low-carbon steel plate without carcinogens of chromium, chromium metal, nickel metal and nickel alloy in a mould pressing manner; casting a frying pan with the diameter of 32-38 cm for families and restaurants and a frying pan main body part with the diameter of 56-108 cm for a group large dining room by adopting gray cast iron and nodular cast iron, removing burrs, grinding edges, performing sand blasting treatment on the frying pan main body part by using alumina powder on the cast frying pan main body part and a mould pressing frying pan main body part with high quality requirement, performing nitriding or nitrocarburizing process on the mould pressing or cast formed frying pan main body part, controlling the nitriding temperature and nitriding heat preservation time process parameters of the selected specific nitriding or nitrocarburizing process, and enabling the surface of the frying pan to generate a nitriding layer with the thickness of 0.20-0.42 mm and very strong wear resistance and corrosion resistance, even if particles which are frequently collided and ground by a metal frying shovel in the frying operation process enter dishes and enter a human body digestion system, wherein the particles are iron and trace nitrogen which have no carcinogenicity and no sensitization to human bodies, Carbon.