产品

低温脆性冲击试验机

型号：BWD-C

国产低温脆性试验仪厂家  结构原理

A、本设备由制冷压缩机主机体、加热装置、电子控制箱、冷却槽、冷却介质循环系统、自动报警装置等部分组成。启动制冷开关后，压缩机开始工作，制冷系统进入正式工作状态。制冷压缩机连续不断的工作，当接近设定温度时，冷却槽中的加热装置开始按比例提供热量，用以平衡制冷系统产生的多余冷量，以达到恒温的目的。搅拌可使冷却槽内的冷却介质不断循环，使温度均匀一致。

B、试样夹持器

试样一边夹持4个试样（橡胶类），另一边夹持15个试样（塑料类）。

C、冲击装置

冲击装置由冲击锤和自锁机构组成。

D、冲击器

冲击头半径为1.6?0.1mm；

冲击时，冲击头和试样夹持器之间间隙为6.4?0.3mm；

冲击头的中心线与试样夹持器之间的距离为8?0.3mm。

国产低温脆性试验仪厂家  使用方法 

1接通电源，温控仪和计时器显示灯亮。 

2向冷井中注入冷冻介质（一般为工业乙醇），其注入量应保证夹持器的下端到液面的距离为75?10mm。 

3将试样垂直夹在夹持器上。夹的不宜过紧或过松，以防止试样变形或脱落。 

4按下夹持器，开始冷冻试样，同时启动时序控制开关（或按动秒表）计时。试样冷冻时间规定为3.0?0.5min。试样冷冻期间，冷冻介质温度波动不得超过?1℃。 

5提起升降夹持器，使冲击器在半秒钟内冲击试样。 

6取下试样，将试样按冲击方向弯曲成180?，仔细观察有无破坏。 

7试样经冲击后（每个试样只准冲击一次），如出现破坏时，应提高冷冻介质的温度，否则降低其温度，继续进行试验。 温度，如这两个结果相差不大于1℃时，即试验结束。 

技术参数:

1.控温范围：室温-70℃（室温≤25℃）

2.恒温精度：?0.3℃       

3.降温速度：0℃～﹣30℃    约2.5℃/min

﹣30℃～﹣40℃   约2.5℃/min

﹣40℃～﹣70℃   约2.0℃/min

4.最大外形尺寸：900?500?800mm（长?宽?高）

5.工作室有效工作空间：280?170?120mm（长?宽?高）    

6.可装试样数量：1

7.数字计时器数字计时器：0秒-99分钟，分辨率1秒

8.冷却介质：乙醇或其他不冻液

9.搅拌电机：8W

10.工作电源：220V--240V，50Hz，1.5kW

11.工作温度:≤25℃

 Low temperature brittle impact testing machine
Model: BWD-C
Structural Principles
A、 This equipment consists of a refrigeration compressor main body, heating device, electronic control box, cooling tank, cooling medium circulation system, automatic alarm device, and other parts. After activating the refrigeration switch, the compressor starts working and the refrigeration system enters the official working state. The refrigeration compressor works continuously, and when it approaches the set temperature, the heating device in the cooling tank begins to provide heat proportionally to balance the excess cooling generated by the refrigeration system, in order to achieve constant temperature. Stirring can continuously circulate the cooling medium in the cooling tank, making the temperature uniform and consistent.
B、 Sample holder
Clamp 4 rubber samples on one side and 15 plastic samples on the other side.
C、 Impact device
The impact device consists of an impact hammer and a self-locking mechanism.
D、 Impactor
The radius of the impact head is 1.6 ? 0.1mm;
During impact, the gap between the impact head and the sample holder is 6.4 ? 0.3mm;
The distance between the centerline of the impact head and the specimen holder is 8 ? 0.3mm.
Usage method
1. Connect the power supply, and the temperature controller and timer display lights will turn on.  
Inject freezing medium (usually industrial ethanol) into the cold well in two directions, and the injection amount should ensure that the distance from the lower end of the clamp to the liquid level is 75 ? 10mm.  
3. Vertically clamp the sample onto the gripper. The clamp should not be too tight or too loose to prevent deformation or detachment of the sample.  
Press the gripper to start freezing the sample, and at the same time, activate the timing control switch (or press the stopwatch) to start timing. The freezing time for the sample is specified as 3.0 ? 0.5min. During the freezing period of the sample, the temperature fluctuation of the freezing medium shall not exceed ? 1 ℃.  
Lift the lifting gripper and allow the impactor to impact the specimen within half a second.  
Remove the sample and bend it 180 ? in the direction of impact, carefully observing for any damage.  
After the impact of 7 samples (each sample is only allowed to be impacted once), if damage occurs, the temperature of the freezing medium should be increased. Otherwise, the temperature should be lowered and the test should continue. When the temperature difference between these two results is no more than 1 ℃, the experiment ends.  
Technical parameters:
1. Temperature control range: room temperature -70 ℃ (room temperature ≤ 25 ℃)
2. Constant temperature accuracy: ? 0.3 ℃
3. Cooling rate: 0 ℃ to -30 ℃, approximately 2.5 ℃/min
-30 ℃ to -40 ℃, approximately 2.5 ℃/min
-40 ℃ to -70 ℃, approximately 2.0 ℃/min
4. Maximum external dimensions: 900 ? 500 ? 800mm (length ? width ? height)
5. Effective workspace in the studio: 280 x 170 x 120mm (length x width x height)
6. Number of samples that can be loaded: 1
7. Digital timer: 0 seconds to 99 minutes, resolution of 1 second
8. Cooling medium: ethanol or other non freezing liquid
9. Mixing motor: 8W
10. Working power supply: 220V -240V, 50Hz, 1.5kW
11. Working temperature: ≤ 25 ℃

传热介质

在试验温度下，能保持流动，对试样无附加影响的液体均可作传热介质。这类传热介质通常使用乙醇，此外还有丙酮、硅氧烷等。

试验报告

A本标准名称或编号

B样品的详细说明及其来源

C使用的传热介质、致冷剂或其他降温方式

D程序A:脆性温度和试样破坏现象

E程序B：规定的试验温度和试验结果

试样规格：

试样的长度为（20.5?0.5）MM，宽度为（6.0?0.5）MM，厚度为（2.0?0.2）MM.

冲击器

冲击器头部形状和尺寸，冲击器的质量为（200?20）g,其工作行程为（40?1）mm。冲击装置的弹簧在压缩状态下，冲击器端部到试样的距离为（25?1）mm。

低温测温计

采用最小分度不大于1度的低温测温计测量冷冻介质的温度，可使用低温温度计、热电偶、电阻温度计等。低温温度计为内标式半浸的，以尾长150MM，浸入液体深度75MM为宜。

组成

设备由工作台、升降夹持器、冲击装置、低温测温计、盛装冷冻介质的低温容器、搅拌器等部分组成。

升降夹持器

升降夹持器由夹持器和升降装置组成

从试样受冲击部位，到夹持器下端的距离为（11.0加或等于0.5）mm。

冲击装置

冲击装置由冲击器和冲击弹簧等组成。

试样要求：

试验前，试样应放置在标准实验室温度下调节至少3H，并在明亮的光线下弯曲试样并检查试样表面，试样表面应光滑，无杂质、损伤及微孔。成品应经打磨后裁制成相应尺寸。

试验结果与处理

程序A

1、试样出现破坏的最高温度，就是该试样的脆性温度。

2、温度值应精确到1度。

程序B

如果一组试样中没有任何1个试样破坏，则试验结果为无破坏。如果一组试样中有2个或2个以上试样发生破坏，则试验结果为破坏。如果一组试样中只有一个试样发生破坏，则再次取3个新的完好试样测试，3个试样均未发生破坏则试验结果为无破坏；否则试验结果为破坏。

 Heat transfer medium

At the experimental temperature, liquids that can maintain flow without any additional impact on the sample can be used as heat transfer media. This type of heat transfer medium usually uses ethanol, in addition to acetone, siloxane, etc.

Test report

Name or number of this standard

Detailed description and source of sample B

The heat transfer medium, refrigerant or other cooling methods used by C

D Program A: Brittle Temperature and Sample Failure Phenomenon

E program B: specified test temperature and test results

Sample specifications:

The length of the sample is (20.5 ? 0.5) mm, the width is (6.0 ? 0.5) mm, and the thickness is (2.0 ? 0.2) mm

Impactor

The shape and size of the impactor head, the mass of the impactor is (200 ? 20) g, and its working stroke is (40 ? 1) mm. The spring of the impact device is compressed, and the distance from the end of the impactor to the specimen is (25 ? 1) mm.



Low temperature thermometer

Low temperature thermometers with a minimum division of no more than 1 degree can be used to measure the temperature of the frozen medium, including low-temperature thermometers, thermocouples, resistance thermometers, etc. The low-temperature thermometer is an internal standard semi immersion type, with a tail length of 150mm and a liquid immersion depth of 75mm.

form

The equipment consists of a workbench, a lifting clamp, an impact device, a low-temperature thermometer, a low-temperature container for holding the freezing medium, a stirrer, and other parts.

 

Lift gripper

The lifting gripper consists of a gripper and a lifting device

The distance from the impact site of the specimen to the lower end of the gripper is (11.0 plus or equal to 0.5) mm.

 

Impact device

The impact device consists of an impactor and an impact spring.

Sample requirements:

Before the experiment, the sample should be placed at a standard laboratory temperature for at least 3 hours and bent under bright light to inspect the surface. The surface of the sample should be smooth, free of impurities, damage, and micropores. The finished product should be polished and cut to the corresponding size.

 

Experimental results and processing

Program A

1. The highest temperature at which the sample fails is the brittle temperature of the sample.

2. The temperature value should be accurate to 1 degree.

Program B

If none of the samples in a group are damaged, the test result is considered undamaged. If two or more samples in a group fail, the test result is considered as failure. If only one specimen in a group is damaged, three new intact specimens shall be taken for testing. If none of the three specimens are damaged, the test result shall be considered as no damage; Otherwise, the test result will be destructive.