Quality Assurance

Yuhua Fused Cast

Quality Control

Henan Yuhua Fused Cast Refractory Co.,Ltd. has a number of high-quality, high-tech management personnel, and the effective operation of the ISO9001 international quality system is a strong guarantee of product quality. Production management, strengthen the implementation of the safety operating procedures for each position in each workshop, requiring workers to strictly follow the company's production management system and job operation standards, from raw materials, sand making, high-temperature casting, heat insulation out of the box, processing and quality inspection into the warehouse, assembly and packaging of a full set of operating instructions standards, and to ensure that all processes in accordance with the standard of the operating instructions to be completed in strict accordance with the standards.

Six Testing Guarantees

Raw material secondary testing

Raw material secondary testing

The core raw materials of Yuhua products are selected from Australian zircon sand, and each batch can be put into storage only after chemical analysis and acceptance; secondly, before the raw materials are put into production, all the raw materials are subjected to the secondary composition test to ensure that the raw materials used are always in high quality.

Real-time monitoring of melting and casting process data

Real-time monitoring of melting and casting process data

Melting control is the key in the electric furnace melting process. Yuhua melting through intelligent technology, real-time monitoring of the whole process of electric furnace melting and casting, to maximize the assurance of stable melt quality.

Casting process chemical composition analysis

Casting process chemical composition analysis

After the raw materials are melted at high temperature, the samples are taken immediately after the melting and casting is completed. The inspectors carry out chemical analysis by means of high-precision atomic absorption spectrophotometer and X-ray fluorescence spectrometer to ensure that the chemical composition of the products can accurately meet the customer's index requirements.

Semi-finished products inspection

Semi-finished products inspection

Inspectors through the appearance of semi-finished products, size, chemical composition and other inspections, identification, sorting, rejection of unqualified blanks, and decide whether to accept the product or batch of products. Ensure that unqualified products are not transferred to the next process; semi-finished product inspection is an important process of product quality control of Yuhua Fusion, which can effectively prevent or reduce the generation of unqualified products.

Finished product appearance size and physical and chemical index inspection

Finished product appearance size and physical and chemical index inspection

Finished product appearance and size inspection: All the factory products are measured in detail using precise measuring tools for their appearance (whether there are gaps, cracks, and surface flatness), weight, processing accuracy, and size to ensure that there are no appearance defects and flaws in the products. Physical and chemical index test: Highly precise testing equipment is used to test the anti-erosion, apparent porosity, glass phase initial precipitation temperature, gas and water content of the products.

Product internal structure flaw detection

Product internal structure flaw detection

Introducing the American handheld non-destructive flaw detector, without damaging the products, we scan the internal structure of each product through radar detection, so that we can quickly and accurately grasp the internal structure of the product before it leaves the factory, and prevent defective products from leaving the factory.

Production Processes

16 key production processes, strict quality control

3D drawing

01

3D drawing

Can provide a more intuitive and comprehensive view of the design, making it easier for glass kiln builders to check details and virtually assemble in three dimensions to better understand the feasibility and performance of the design. This intuition not only helps to identify problems at the drawing review stage, but also helps to accurately check the accuracy of drawing dimensions and list data through virtual assembly (assembly), which helps to improve efficiency and reduce the error rate of drawing lists.
3D CNC Film Cutting

02

3D CNC Film Cutting

Yuhua Fusion utilizes digital control technology for the fabrication of three-dimensional object models. The 3D CNC machine controls the displacement of equipment and tools through digital information to achieve accurate model processing and molding. According to the drawings provided by the customers, the accurate model of electrofusion bricks is quickly made by 3D CNC technology. This technology not only improves the manufacturing efficiency, but also makes complex shaped bricks with high accuracy, and does not affect the accuracy of sand molding due to the size error caused by human factors.
One-piece mold sand mold production

03

One-piece mold sand mold production

The traditional production of electrofused zirconium corundum refractory products with sand mold plate multi-block combination, splicing, fixed way; in the type plate group type, often around the thickness and tightness of the insulation sand can not be exactly the same, the cooling speed is not consistent; plane and bonding seam cooling speed is not consistent, which will cause stress and cracks. One-piece sand process used for the whole sand, a complete whole cavity, around the tightness and thickness of the insulation sand is the same, after casting the brick body solidification and balanced, will not be due to stress and cracks, thus solving the brick cracks and collapse of the cracks, while avoiding the size difference caused by the grouping of the type to ensure the accuracy of the product dimensions, reducing the amount of processing, so that the surface of the dense layer of thickening. The products produced by this process effectively improve the service life of the glass kiln!
Raw material sampling and testing

04

Raw material sampling and testing

The raw materials required by Yuhua Fusion Technology are selected from Australia ILUKA zircon sand, China Alcoa Group (Henan Aluminum) alumina powder, and desiliconized zirconium from Fujian Sanxiang New Material Co. Each batch of raw materials is analyzed by sampling and chemical composition before it is put into storage. Before the raw materials are put into production, all the raw materials are inspected by sampling composition for the second time to ensure that the raw materials used are always in high quality.
Automated batching system

05

Automated batching system

Scientific control system is the foundation of fusing and casting high quality electrofused bricks, Yuhua Electric Fusion has always insisted on realizing all-round control of the production process through scientific quality control to produce products with stable quality. Yuhua Electric Fusion takes the lead in updating the use of automatic electronic batching system. The batching system has high degree of automation, high weighing precision, high mixing uniformity, and can reduce human error, which is an important link for the stability of the chemical composition of the products.
High-temperature melting and casting

06

High-temperature melting and casting

The equipped raw materials will be added into the electric melting furnace and heated to a high temperature above 1900~2000℃ to make the raw materials melt. In this process, the raw materials will go through the melting process of electro-melting method, that is to say, the raw materials will be melted by the high temperature of the electric arc furnace. During the whole melting process, Yuhua Electric Melting carries out real-time monitoring of the melting temperature, melting time, oxygen blowing time, and casting temperature, casting time, and casting volume to ensure that all the procedures of the melting and casting process are strictly completed in accordance with the standards of the operation guide. Melting and casting is the most important thing for the production quality of electrofused bricks.
Furnace material sampling laboratory testing

07

Furnace material sampling laboratory testing

Raw materials after high temperature melting, melting and casting is completed immediately sampling. The inspectors carry out chemical analysis by means of high-precision atomic absorption spectrophotometer and X-ray fluorescence spectrometer to ensure the qualification, accuracy and stability of the chemical composition of the products. For more than twenty years, Yuhua Melting has always insisted on one inspection for one furnace and uploaded the inspection records in time to save the samples, and the sampling samples are kept for no less than 6 years.
Insulation annealing

08

Insulation annealing

Insulation annealing of electrofused bricks is a key process for quality control. Insulation annealing of electrofused bricks mainly involves placing the casting model in the insulation box before casting, and using insulation sand to fill in the bottom and around the insulation box, and then covering the insulation sand for insulation annealing after casting. Electrofused bricks in the cooling process, due to the ZrO2 from the high temperature cubic crystal system to the low temperature monoclinic crystal system of crystalline transformation, the volume will be a sharp expansion, in order to avoid cooling too fast to produce large thermal stresses and lead to cracking of the products, to strengthen the heat preservation measures is essential. Therefore, in the crystallization process of electrofused bricks, the cooling speed is controlled by heat preservation and annealing to avoid too large a temperature difference between the casting and the annealing heat preservation medium, so as to ensure the uniformity of the internal structure of the electrofused bricks and the high temperature performance.
Semi-finished products out of the box acceptance

09

Semi-finished products out of the box acceptance

The production process according to the product castings of different volumes, processes, materials, specifications and models, the development of the corresponding insulation time, to the internal crystallization of electrofusion bricks to create superior conditions. Yuhua electrofusion in the production control, the control of insulation time is quite rigorous, and resolutely put an end to the phenomenon of early out of the box, out of the box in violation of the law! After the product insulation due out of the box, the inspectors of each semi-finished brick (blank) appearance size, surface flatness, corner flute integrity, product theoretical weight, crack defects and other acceptance assessment, and resolutely put an end to unqualified products transferred to the next process.
Precision cutting and fine grinding

10

Precision cutting and fine grinding

The electrofusion bricks are equipped with specific diamond grinding wheels and diamond fine grinding discs by professional processing equipment, and the bricks are ground in multiple rounds according to the size requirements of the drawings until the surface is smooth and bright, and the dimensions are accurate! Processing process in strict accordance with the requirements of electrofusion brick processing guidebook fine grinding, excellence; to eliminate the existence of rough edges, missing corners and edges, dents, size deviation and other phenomena, for the overall quality of the assembly of the kiln to provide efficient protection.
Acceptance of Finished Brick Processing

11

Acceptance of Finished Brick Processing

All ex-factory products are measured in detail using precise measuring tools for their appearance (whether there are bumps, cracks, and surface porosity exceeding the standard phenomenon), weight, processing accuracy, and dimensions to ensure that there are no defects in the appearance of the product and dimensional deviations.
Sampling and testing of finished bricks

12

Sampling and testing of finished bricks

Samples are taken in batches with high-precision testing equipment in accordance with national standards, and key indexes such as erosion resistance, apparent porosity, glass phase initial precipitation temperature, bubble precipitation rate, glass phase exudation, etc., and the test results and samples are archived and preserved for a minimum period of 6 years. Yuhua Electric Fusion provides solid guarantee for the stable operation of glass melting kiln.
Radar Flaw Detector Inspection

13

Radar Flaw Detector Inspection

Yuhua Electric Fusion introduces the American handheld non-destructive flaw detector, which scans the internal structure of each product through radar inspection without damaging the product, so that it can quickly and accurately grasp the internal structure of the product before it leaves the factory, and put an end to the defective products leaving the factory. The use of radar flaw detector on important parts of glass kiln such as pool wall, bulge, kiln can, liquid flow hole, etc. has largely improved the safety and stability of glass kiln operation, which is unanimously recognized and praised by customers.
Pre-assembled spray code

14

Pre-assembled spray code

When building glass kilns, the quality of fused zirconium corundum bricks in areas such as the spout, the flow hole, the working pool, the feed opening, the kiln door, and so on, is particularly demanding. In order to meet these requirements and also to shorten the construction time of the furnace or the hot repair time of the glass kiln, YUHUA FUSION pre-assembles electrofused zirconium bricks on a special assembly table. All electrofused zirconium corundum bricks should be printed with a logo according to the requirements of the national standard on the marking of refractory products and zirconium corundum bricks. The marking is printed on the working and casting surfaces of the brick. Each piece of electrofused zirconium corundum brick is printed on the working surface with a color that is not easy to be brushed off with the number and trademark of YUHUA Electrofusion, material and weight. The assembly of the matching electrofused zirconium corundum bricks has a special connection symbol to ensure high quality and efficiency in the subsequent construction.
Overall acceptance of assembly size

15

Overall acceptance of assembly size

Yuhua electric kiln assembly is completed, in strict accordance with the requirements of the company's assembly standard guidebook, the first self-inspection, self-inspection, including: assembly size to meet the requirements of the drawings, surface flatness, the brick body has no unevenness and lack of corners and edges, the assembly of the gap, especially the liquid-flow holes, kiln cans, bulging bubbles and other locations, the gap can not be > 0.5mm, diagonal deviation, swan height, swan span, and so on. After the self-inspection is completed, the operation department will notify the customer of on-site acceptance and make a record of on-site acceptance.
Packing and shipping

16

Packing and shipping

After the customer acceptance, if there is no special packing requirement, we will pack the products strictly according to the standard of wooden case packing for export of Yuhua Electrofusion. Each brick and brick to do a good job between the protective compartment, to ensure the safety of each product, and with the delivery of the vehicle with the sales list, packing list details, assembly marking chart, inspection reports, certificates of compliance, weighing sheets and other effective proof, in accordance with the customer's designated address or port of receipt for shipment, and sign the transport insurance and other transport contracts, safe shipment!