Gypsum laboratory
The most important department of any production unit which has the task of controlling gypsum quality is the laboratory. This department should the qualification and facilities needed to test and present the results needed.
The control quality laboratory of kazeroon gypsum co. exists and operates as an independent unit within the company with the purpose of continuous maintenance, elevation and improvement of the products’ quality. And by having and making use of accurate lab facilities and experts, our laboratory performs special and accurate tests for producing standard products with the aim of increasing the quality factor. The scope of activities of control quality unit as aligned with production unit ranges and is necessary from the most preliminary phase (the entry of raw materials) to the most final phase (deliver product to the customer). To that end the examinations and controlling the process is based on the following controls:
- Controlling the process of product’s production
- Sampling the productions
- Examining and inspecting the samples
- Controlling the entry materials
- Controlling during the production with purpose of preemptive actions
Laboratory equipment
Quality control laboratory in a gypsum production unit, in order to perform correct chemical, physical and mechanical examinations according to related national standard and other standards related to the said production unit, should include all the needed equipment related to sampling, measurement and examination. In order to achieve the needed accuracy and correctness of examinations, the equipment should be capable and match the specifications related to the examinations. In regards to quantity or the key values of machines, in the cases that these specifications has an important impact on the results, Calibration programs should be implemented. Before making use of facilities, they should calibrated or inspected to make sure that they do in fact meet the needed standards.
Also all the laboratory equipment which needs calibration should be labeled in order show the calibration status including last calibration date and the renewing calibration date or the standards for expiration of last calibration.
The equipment should be used by authorized personnel only. The instructions about maintaining equipment and the correct way to use them should be easily available in order for the laboratory staff to use them. The laboratory management should make sure of the eligibility of all the personnel who are using specific equipment.
In the case of using in-training personnel there should adequate supervision. The laboratory personnel depending of the need, in regards to education, experience and skills should be eligible.
The minimum needed equipment and materials in a gypsum laboratory includes:
Devices :
- Ovens: this device is used for drying the sample in order to analyze the gypsum. Another use of this device is drying the gypsum frames which come out of the humidity chamber, and in both steps the proper temperature is 40°C.
- Resistance machine: this device is used for breaking the gypsum’s frames and testing the Bending and compressive strength. According to our configuration he measurement unit of device could be N/mm2 or kg/cm2 .
- Laboratory scale: scale is used for weighing samples which depending on the test it can be done According to different accuracies. In a gypsum laboratory two type of scale with accuracies of 0.1 and 0.0001 is needed.
- Laboratory water bath: this device is used for Evaporation of acidic solution of gypsum with a very slow speed. Then accuracy of this device is higher than a heater and the solution evaporates and decomposes slowly.
- Electric arc furnace with capability to measure at least 1000 degrees Celsius: this device is used to create high temperatures. The use of it in chemical tests is burning the filter paper with sediment. the filter paper with sediment is usually ashless.
- Modified vicat device (densimeter): this device is used for getting a water to normal plaster ratio.
- humidity chamber: this device is used for processing of gypsum samples in mechanical test. For this purpose samples should be placed inside the chamber with a temperature of 23°C and relative humidity of 45 to 55 percent for a duration of one week.
- Desiccator: this device is used to accelerate the cooling of the samples to ambient temperature without absorption of peripheral humidity.
- Whiteness color meter