To help users assess the quality of fused quartz equipment, this article briefly introduces the identification methods for fused quartz equipment quality.

Outer and inner quality both determine the quality of glass-lined equipment. Outer quality can be qualitatively assessed through visual inspection and instrumental testing, whereas inner quality refers to the microscopic, intangible defects hidden within the equipment due to improper material selection, shaping, welding, surface treatment, and firing processes during manufacturing, as well as inadequate quality control in each stage. These defects can become apparent during transportation, storage, or use, leading to equipment failure. Inner defects cannot be detected by any means and can only be minimized through rigorous quality management and scientific, reasonable process discipline. This means that every step in the manufacturing process of glass-lined equipment must be strictly controlled to ensure the quality of each unit. However, in the current intense market competition, many companies find it challenging to achieve this. As an industry leader, our company can guarantee the quality of our products. We assure all customers that they can use our products with confidence. Currently, there is a widespread presence of poorly made, cost-cutting, and substandard equipment in the market.

Below, we introduce some knowledge on identifying the quality of glass-lined equipment.

The quality of the outer surface of glass-lined equipment can largely reflect the inner quality's excellence or deficiency.

It appears to be a glass-lined equipment.

Wipe the surface dust from the glassware with a dry cloth (not a wet one). Inspect under normal lighting; the glass surface should be shiny. If the porcelain surface is as clear as a mirror, allowing for a clear reflection of one's face, it is considered high-quality. Additionally, carefully examine the glassware surface for the absence of the following defects:

Should be dense without any small pores.

b. The product should be free of glaze nodules, blisters, stubborn impurities, and obvious color discrepancies; for closed vessels over 6300L in size, the porcelain surface, especially at the manhole, upper and lower junction ring areas, bottom head flange welds, and lower liquid outlet, should not have linear streaks (a term referred to as "streaks" in the professional jargon).

c. The porcelain surface shows no noticeable scratches. Our fused quartz equipment, due to the differences in fusion process compared to foreign counterparts, only the fused quartz layer with a thickness of approximately 0.2mm is dense, with the remainder containing bubbles. This means that the 0.2mm thickness serves as an effective anti-corrosion layer with high strength. Deep scratches can damage this dense layer, reducing the strength of the fused quartz layer. Therefore, it is strictly prohibited to allow hard objects into the fused quartz equipment during inspection, installation, and use to prevent scratching.

d. The fritted surface at the weld seam should be free of any noticeable protrusions. Here's a professional tip: At higher temperatures, the fritted layer on the protruding areas of the metallic substrate (which are the outer arc areas) is subjected to tensile stress due to the difference in thermal expansion coefficients between the fritted layer and the metallic substrate. The fritted layer's tensile strength is significantly lower than its compressive strength, making it prone to cracking under tensile stress. Therefore, it is advisable to minimize the occurrence of protrusions on the metallic substrate, and to grind down any protruding weld seams as much as possible.

The glass frit surface should be free of any noticeable dents. Dents are defects left on the metal substrate steel plate surface after polishing, and the more dents there are, the poorer the surface quality of the steel plate, which is not suitable for glass fritting equipment.

The steel plates at the pipe end and nozzle, manhole and nozzle, high-neck flange and cylinder welding joints should not have any noticeable thickness differences.

Defects mostly occur in large-scale equipment due to manufacturers not processing or selecting suitable pipe ends and high-neck flanges according to the actual thickness of the equipment's steel plates. Instead, pipe ends and high-neck flanges suitable for small-scale equipment are used in large-scale equipment, resulting in thickness differences at the joint. The larger the scale, the more pronounced the thickness difference, which can be as much as 6-8mm in severity. Such sudden changes in metal base thickness are extremely detrimental to the quality of the glass frit layer. Due to significant thickness variations, there are substantial temperature differences during heating and cooling of the equipment during firing, leading to significant temperature stress in the glass frit layer after cooling. During use, stress released due to temperature changes can cause the glass frit layer to break. Additionally, it should be noted that the steep changes in metal base thickness can cause temperature differences during the firing process, leading to inconsistent reaction speeds of the glass frit glaze, resulting in differences in the microstructure of the glass frit layer. In areas with lower temperatures, the entire reaction process is not yet complete, and an ideal microstructure has not been formed when the equipment is removed from the furnace.

This defect is entirely preventable. Its presence highlights the manufacturers' neglect of quality and gaps in management.