OUR PRODUCTS, OUR SERVICES, OUR KNOW-HOW:
Each valve is unique and requires comprehensive solutions to meet customers’ expectations when it comes to configuration, installation, and final application.
We do NOT just simply select the valves and drop them to the customers. Instead, we listen to our customers about what they need, provide our solutions after evaluation, and then we decide what to offer to our customers for their benefits.
Wherever and whenever valves are needed, DAVINCI VALVES will always have its suitable valves, fittings and accessories in position for you. You deserve a partner who can meet all your requirements for a win-win cooperation in the long run.
Your partner of reference.
You deserve DAVINCI VALVES.
So, let´s talk about your project today.
OUR MANUFACTURE PROGRAM IS BASED ON CENTURIES' TRADITION:
THE MATERIALS OF OUR PRODUCTS:
The materials used for DAVINCI VALVES are carefully selected depending on their heat resistance, work pressure performances, medium flowing through the valves, sizes and most importantly, technical specifications required by our customers.
The materials for valve bodies mainly include the following three types: stainless steel, steel, and cast iron.
1.4308 (ASTM A 351 Gr. CF 8)
This kind of steel consists of chromium-nickel alloy and has good corrosion resistance. It also can be given mirror ﬁnish. This stainless steel is mainly used for valves exposed to aggressive medium or environments.
1.4462 (ASTM A 182 Gr. F 51)
This stainless steel belongs to the group of duplex steels. Its micro-structure consists of a mixture of austenitic and ferritic crystal grains which contributes to its high corrosion resistance and excellent strength. It is frequently used for the manufacture of valves installed in aggressive medium or sea water.
1.4571 (ASTM A 182 Gr. 316 Ti)
This type of stainless steel is an austenitic steel and has good weldability, so it doesn’t need to be tempered. It’s also highly corrosion resistant. The application areas of this stainless steel primarily include the manufacture of welded valves suitable for use in aggressive medium.
1.4408 (ASTM A 351 - CF 8 M)This stainless steel is a cast version of chromium-nickel-molybdenum steels and has excellent oxidation resistance. It is primarily used for valves exposed to aggressive medium, for example, the chemical industry.
Structural steel S 355 J 2 WP / S 355 J 2; ASTM A 242 Type 1 / ASTM A 572 Gr. 50
This type of steel is mostly used for constructional steelwork or hydraulic steel construction. It is weatherproof, less susceptible to corrosion and has lower sheet/plate thickness which means it does not need to be pre-heated and it has a smaller seam volume.
Forged steel P 250 GH; ASTM A 105 / ASTM A 668 Class F / ASTM A 516 Gr. 60
The advantage of this type of steel is that it can be used in temperatures of up to 480 °C as it is highly heat resistant and it has great weldability. This forged steel is used for manufacture of forged valves.
Welded steel S 235 JR G 2 / S 235 JR + AR; ASTM A 283 Gr. C
Advantage of welded steel is its great breaking-resistance strength. The utilization of this kind of steel ﬁts in the manufacture of welded valves.
H II P 265 GH; ASTM A 516 Gr. 60
This kind of steel is heat resistant and it is very durable, e.g. it can be used for heat insulation layers. The manufacture of pressure welded valves requires use of this kind of steel.
EN-GJL-250 EN-JL 1040 / GG-25 / ASTM A 48 40 B / EN-JL 1040 Cast iron is an iron-carbon-silicon casting alloy whose lamellar graphite gives the cast iron very good self-lubricating characteristics when it is cut during the manufacture process. What’s good about EN-JL 1040 cast iron is its vibration damping, its castability, its machinability, its resistance to corrosion and its high thermal conductivity.
EN-GJS 400-15 EN-JS 1030 / GGG-40 / ASTM A 536 Gr. 60-40-18 / EN-JS 1030 Cast iron is an iron-carbon-silicon casting alloy in which the graphite is presented in the form of spheroids and the properties of this material are similar to steel in terms of high castability, strength and toughness. What’s good about EN-JS 1030 cast iron is its high elongation at break and its high strength and toughness.
EN-GJS-400-18-LT EN-JS 1025 / GGG-40.3 / EN-JS 1025 Cast iron is an iron-carbon-silicon casting alloy in which shares the similar advantages as EN-GJS 400-15 EN-JS 1030 / GGG-40 / ASTM A 536 Gr. 60-40-18 / EN-JS 1030 cast iron mentioned earlier. This material can perfectly ﬁt in applications for valves with low temperatures or higher nominal pressures.
All our valves are submitted to working pressure, leakage and function tests. Besides those, we also provide diﬀerent speciﬁc types of testing that are committed to the assurance of DAVINCI VALVES’ product qualities.
Coating Thickness Testing
Magnetic induction method is used to measure the thickness of coatings or corrosion-inhibiting coating agents. This enables non-destructive testing of coat thickness or coat agents. The minimum coat thickness of our products (if any) is 250 µm. No bubbles shall develop in the coating during this test.
Paint Adhesion Testing
The Pull-oﬀ test is used to test how well the coating is applied to the substrates. The minimum adhesion on the core and the molding sand sides is tested with a pulling force of >12N/mm2. The testing samples are immersed for in deionized water at 90ºC for seven days and then dried in an oven for 3 hours. A conditioning phase from 3 to 5 days in normal atmosphere is then allowed to elapse. No bubbles may arise during the period when immersed in the water bath. The surface of the testing sample is degreased and roughened with abrasive paper and then recleaned after cleaned from dust with oil-free compressed air.
Impact Resistance Testing
A pendulum which hits the coated surface with an energy of 5Nm at a ﬁxed distance is used for impact testing. After each impact the component is electrically tested as no electrical breakthrough shall occur.
The coating is checked for its porosity by using a high voltage testing device at a deﬁned test voltage. The test is performed using rubber electrode. The coating must be completely free of penetrating pores so as to avoid subsequent corrosion of the casting underneath.
The cathodic inﬁltration test is a corrosion test that is carried out at 23ºC for a period of 30 days. A defect is created on the coated surface of the test specimen, which is subjected to cathodic polarization in a sodium chloride solution for the entire test period.
Cross linkage Testing
At room temperature, drop a drop of methyl isobutyl ketone on the surface of the horizontal epoxy-coated sample. After 30 seconds, wipe the test area with a clean white cloth. Check that the test surface has not become neither dull nor stained, and that the cloth is kept clean. The test is carried out 24 hours after the coating process.
Among all QUALITY and GUARANTEE Certificates we’d provide you with, there is one we want to particularly point out, and that is Potable Water Specific WRAS Approval Certificate for our gate valves, which will assure you the best conditions of our gate valves for your potable water installations.
What is a WRAS Approval?
Whether you’re a tradesperson or a facility manager, you’ve probably come across products bearing the WRAS seal of approval - but what exactly does WRAS Approval stand for, and why is it so important?
The WRAS, or Water Regulations Advisory Scheme, is a conformance mark that demonstrates that an item complies with high standards set out by water regulations in the United Kingdom since 1999. It is now a subscription-based accreditation body whose subscribers are 26 UK Water Suppliers.
The WRAS contains an approval system which functions as a way for plumbing manufacturers to demonstrate that their products, such as taps, valves and boilers, comply with the standards.
Once submitted by the manufacturer, a product will only gain approval after undergoing rigorous mechanical and water quality testing by independent laboratories. The product may also need to meet certain installation conditions in order to obtain a WRAS Approval.
The approval system also covers non-metallic components and materials (such as rubber washers and gaskets), in which testing is conducted to ascertain their effects on the water with which they come into contact. Some materials can give the water an undesirable flavor or odor, as well as causing cloudiness or discoloration. Others can contain toxic chemicals that affect the water or create conditions that allow bacterium and microbes to flourish. A WRAS approval will only be given once it has been demonstrated that the components do not contaminate the water in any way.
Once granted, the WRAS Approval lasts for a maximum of five years, after which the products will need to be resubmitted for assessment.
ASK FOR YOUR WRAS CERTIFICATE TODAY!
FOR ALL PROFESSIONALS WHO ATTEND
WORLDWIDE VALVES EVENTS:
DAVINCI VALVES is proactive in attending important events and international fairs associated with valves all over the world. You may always get us in touch by E-mail: email@example.com
or we can have meetings in person at events or fairs, such as:
AQUATECH (Shanghai, China) FLOWTECH (Shanghai, China) VALVE WORLD EXPO (Düsseldorf, Germany) WIE TEC (Shanghai, China) AQUATECH (Amsterdam, Holland) POLLUTEC (Lyon, France) IFAT (München, Germany)