Some standard content:
JB/T8834--2001
This standard is a revision of IB/T8834-1999 "Shell (core) phenolic resin for casting". This standard is mainly based on the technical progress of shell (core) phenolic resin for casting in recent years and the quality requirements of advanced shell and core processes for this resin. The relevant technical conditions (including free phenol, fluidity, melting point, softening point, etc. of the resin) have been revised accordingly. And the index of room temperature bending strength has been introduced in the classification. This standard replaces JB/T8834--1999 from the date of implementation. This standard is proposed and managed by the National Technical Committee for Foundry Standardization. The drafting units of this standard are: Shenyang Foundry Research Institute, China Foundry Materials Corporation, Huazhong University of Science and Technology, First Automobile Group Corporation, Hebei Chengde Modeling Materials Corporation, Tongliao Dalin Shengda Molding Sand Co., Ltd., Gaizhou Hengda Chemical), Jinan Qianli Chemical, Hubei Shiyan Jinqiu Chemical Company, Suzhou Wuxian Lumu Resin Factory. The main drafters of this standard are Wang Yan, Liu Weihua, Lv Dezhi, Jin Guangming and Han Wenjing. This standard was first issued in February 1989 as ZBG39005-1989, and the standard number was adjusted to JB/T88311999 in April 1999. This is the ·th revision.
1 Scope
Machinery Industry Standard of the People's Republic of China
Phenolic resin of mould(core)forfoundry
Phenolicresinofmould(core)forfoundryJB/T 8834..2001
ReplacesJB/T 8834--19
This standard specifies the classification, brand, technical requirements, test methods, inspection rules, packaging and transportation of phenolic resin of mould(core)forfoundry. This standard is applicable to synthetic resins made by condensation of phenol and formaldehyde as the main raw materials. Its main purpose is to prepare the binder for the shell (core) thermal coated sand.
Cited standards
The clauses contained in the following standards constitute the clauses of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised. The parties using this standard should explore the possibility of using the latest version of the following standards. GB/T8146—1987 Rosin test method
JB/T 8583-1997
Casting coated sand
HG 5-13421980
Determination method of free phenol content in phenolic resin 3 Terminology
3.1 Shell (core) phenolic resin
Thermoplastic resin made by condensation of phenol and formaldehyde as the main raw materials. It can be used as a binder for casting shell (core) thermal coated sand. 3.2 Flowability
The distance that the shell (core) phenolic resin flows on the specified test device at the specified time and temperature. 4 Grading and brand
For the classification of shell (core) phenolic resin for casting according to softening point, see Table 1. Table 1
Grading code
Overflow range, C
>80～90
For the classification of shell (core) phenolic resin for casting according to room temperature flexural strength, see Table 2. Table 2
Grading code
Strength range.MPa
Casting shell (core) phenolic resin classification according to polymerization rate see Table 3.4.3bzxz.net
Grading code
Polymerization rate,
20～30
Approved by China Machinery Industry Federation on 2001-05-23 542
>30～40
>90～100
>40~50
>100～10
≥50-60
Implemented on 2001-10-01
4.4 Brand||tt ||JB/T8834-2001
The grades of core phenolic resin for casting are as follows: ZKF
Strength classification code
Softening point classification code
Shell type (core) phenolic resin for casting (casting, shell, phenol are the first letter of the Chinese pinyin) Example: ZKF95-7
5 Technical requirements
5.1 The appearance of shell (core) phenolic resin is yellow transparent solid in strips, granules or sheets. 5.2 The softening point, polymerization rate, free phenol, fluidity, melting point of coated sand, tensile strength of coated sand at room temperature and other indicators of shell (core) phenolic resin shall comply with the requirements of Table 4.
Softening point (Ring and Ball Method), C
Free phenol (Bromide Method), %
Flowability (Inclined Plate Method), mm
Polymerization Rate (Hot Plate Method). S
Flexural Strength of Coated Sand at Room Temperature, MPa
ZKF--75-×
ZKF---85-×
>80～90
>90～100
60~~110
ZKF --105-
=100-- 105
5.3 If the purchaser has special technical requirements for other properties of shell (core) phenolic resin (such as hot tensile strength, shelling resistance, etc.), the supply and demand parties can determine them in the order agreement.
6 Test method
6.1 Softening point
Perform according to the provisions of GB/T8146.
6.2 Polymerization speed
6.2.1 Instrument
Measurement plate: Made of gray cast iron, its shape and size are shown in Figure 1; Electric furnace: 600~~800W;
Porcelain mortar;
Stopwatch;
Thermometer: 0~~200℃, scale 1℃
Steel scraper: 150mm×20mm×lmm.
6.2.2 Determination method
Weigh 9.0g of shell (core) phenolic resin sample and 1.0g of isotretinoin that pass through the casting test sieve with a mesh size of 0.150mm, put them into a porcelain mortar and grind them into a fine powder. Then weigh 1.0g of the mixture and place it in the middle circle of the determination plate preheated to 150°C±1°C (the sample placed in the circle of the iron plate should be flattened). When the resin is completely melted, start timing, and use a scraper to stir and draw the wire continuously (the scraper should be preheated at the same time as the iron plate) until the wire cannot be drawn. The required time (s) is the polymerization rate of the resin. 513
JB/T 8834-
Each sample is tested three times, and the results should be taken as the average value. However, any of the tests should be repeated.
6.3 Free phenol content
Figure] (1:8)
According to the determination method of free phenol content in HG5-1342 phenolic resin. 6.4 Fluidity
6.4.1 Instrument
Fluidity determination plate: made of cast iron, shape and size see Figure 2; electric furnace: 1kW;
Drying box: maximum temperature above 200C, blast; thermometer: 0~200℃, scale 1℃,
Steel ruler: 150mm;
Porcelain mortar.
6.4.2 Determination method
Figure 2 (1:8)
When the difference between the test results and the average value exceeds 10%, the remaining 2
Weigh 9.0g of the shell (core) phenolic resin sample that passes through the casting test sieve with a mesh size of 0.150mm and 1.0g of urotropine, put them into a porcelain mortar and grind them into a fine powder. Then weigh 0.5g of the mixture and pour it into the ?20mm pit on the measurement plate preheated to 80℃±5℃. Then place the measurement plate horizontally in a drying oven at 125℃. After heating for 2 minutes, quickly pick up the measurement plate from the head with the pit and place it on a bracket with an angle of 60° to the horizontal plane. Keep it warm for 15 minutes, then take the measurement plate out of the drying oven and use a steel ruler to measure the length of the resin flow with the center of the 20mm circle as the base point. Express it in mm, which is the fluidity of the resin. Each sample is tested twice, and the results shall be averaged. However, if any test result differs from the average by more than 10%, the test shall be repeated.
6.5 Melting point of coated sand
6.5.1 Preparation of coated sand
6.5.1.1 Instrument
IB/T 8834-2001
TKHZ-SHY, experimental planetary rotor coated sand mixer or other similar mixers (TKHZ-SHY, the trade name of the product provided by China Foundry Material Corporation. This information is given to provide convenience to the users of this standard, and it is not an endorsement of this product by the main arm department of the standard).
6.5.1.2 Formula
The coated sand is mixed according to the following formula:
Standard sand
Shell type (core) Phenolic resin
Hexamethylenetetramine aqueous solution (1:1) (industrial grade) Calcium stearate (chemically pure)
6.5.1.3 Coating process
Urotropine is 12% of the resin amount
Calcium stearate is 6% of the resin amount
First, add 1000g of standard sand into the sand mixer, start stirring and start heating. When the sand temperature is heated to 130~~160 (, turn off the power of the heater, add the resin into the sand mixer, mix the sand by 150%, wait for the sand temperature to drop to 105C, then add the urotropine aqueous solution, mix the sand by 20%, then add calcium stearate, cool it with cooling water, stop the machine when the sand temperature drops below 70C, unload the material and pass it through a casting test sieve with a sieve size of 0.6mm. 6.5.2 Test of the melting point of coated sand
6.5.2.1 Instrument
TKR-SHY, coated sand melting point tester or other similar testers (TKR-SHY is the trade name of the product provided by China Foundry Materials Corporation. This information is given to give this standard It is to provide convenience to the users of the standard, rather than the approval of this product by the standard administration department).
6.5.2.2 Determination method
Turn on the power of TKR-SHY, the coated sand melting point tester, so that the temperature on the surface of the tester forms a temperature gradient increasing from 60 to 180C along the length direction. Spread a layer of coated sand with a width of about 20mm evenly on the metal plate through the funnel. After heating for 60s, start the air blower to move evenly on the top of the sand layer to blow away the uncrusted floating sand. The temperature at the lowest end of the crust of the coated sand on the temperature gradient plate is the melting point of the coated sand
6.6 Bending strength of coated sand at room temperature
6.6.1 The preparation of coated sand is the same as 6.5.1.
6.6.2 The measurement of the room temperature flexural strength of coated sand shall be carried out in accordance with the provisions of 6.1 of JB/18583-1997. 7 Inspection rules
The supplier shall inspect each batch of shell (core) phenolic resin, and the measured performance indicators shall comply with the provisions of Chapter 5 of this standard. 7.1
7.2 The buyer shall inspect according to the indicators specified in this standard or agreement. If there are ... indicators in the inspection results that do not meet the requirements of this standard, the sample shall be doubled for re-inspection. If there are still items that do not meet the requirements of this standard in the re-inspection results, the entire batch shall be considered unqualified and the supplier and buyer shall agree on it. | |tt||7.3 If there is a dispute between the supply and demand parties, they may entrust an arbitration unit to make a ruling. The arbitration unit shall be selected by both parties through consultation. 8 Packaging, marking, storage and transportation
8.1 The packaging bags of shell (core) phenolic resin should be moisture-proof and easy to transport. 8.2 The packaging bags should be marked with the manufacturer's name, product name, brand, production date or batch number, and weight. 8.3·For each package of resin, the supplier must provide a product quality certificate. 8.4 It should be stored in a cool, dry and ventilated place, away from fire, and the shelf life is greater than 6 months (25 (below). 8.5 Prevent H from being exposed to the sun and rain during transportation. When the temperature exceeds 35C, appropriate cooling measures should be taken. 545
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