Durable Electric Water Heater: Cold-Rolled & Hot-Rolled Steel Options
When manufacturing electric water heaters, the choice of raw material for the inner tank is critical. Two common types of steel used in this application are cold rolled steel and hot rolled steel.
What is cold rolled steel? What is the difference between cold rolled steel and hot rolled steel? As a non-professional steel production personnel, may not understand this very well. But don't worry,
follow me to find out.
What is cold rolled steel?
Cold rolled steel refers to steel made by cold rolling. Cold rolling is the further rolling of No.1 steel plate to meet the thickness of the steel plate at room temperature. Compared with hot-rolled steel
sheet, cold-rolled steel thickness is more accurate, and the surface is smooth and beautiful, and also has a number of superior mechanical capabilities, especially processing capabilities. Because the
cold-rolled coil is relatively brittle and hard, it is not suitable for processing, so in general, the cold-rolled steel plate needs to be annealed, pickling and surface leveling before being handed to the
customer.
Although cold-rolled steel is more expensive than hot-rolled steel, its advantages allow it to be used in many applications. Because the surface is already very smooth, the finished product does not
require a large amount of additional surface finishing. Cold rolled steel applications include: metal furniture, household appliances, metal containers, pans and computer cabinets.
What is the difference between cold rolled steel and hot rolled steel?
The difference is not the smelting process, but the rolling temperature, that is, the rolling end temperature. The final rolling temperature is less than the recrystallization temperature of the steel is
cold-rolled steel. Hot rolled steel is easy to roll and has high performance, but the steel is oxidized under hot rolling, and the product surface is black and gray.
The raw material used by our company is cold-rolled steel, which has the following advantages:The cold-rolled steel is much more durable and plastic than the hot-rolled steel used by thr most famous
world brands for storage water heater.In such a case steel has a more smooth surface which significantly strengthens the grip of protective enamel coating and prevents the apperance of micro cracks.
The durabolity of the inner tanks coating is the key to long life of water heater.Tiny air bubbles or micropores in the coating can lead to pitting and water heater's failure.
For water heater tanks, cold rolled steel is often the first choice because it has a superior surface quality that helps reduce corrosion and extend the life of the tank. Additionally, the tighter tolerances
achieved through cold rolling can result in better insulation and energy efficiency, which are key factors in water heater performance.
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DINGXIN story
One electric water heater branded as Dingxin, which has warmed Mr Chen for 22 years. In 1991,Mr Chen bought a new water heater and normally lived with it as long as 22 years in Wenzhou
The Family business
DINXIN ADVENTURE THROUGH 2 GENERATIONS, FROM THE START IN 1986 TO TODAY.
The family business
The founder –Dong Wanwen– started “Dingxin” (in Wenzhou in 1986, as one of the first water heater manufacture in China. With minimal resources he created the first vented water heater in Wenzhou. He has, during his 30 years in Dingxin, mixed friendly industry and home culture in a unique way and has given Dingxin the recognition as one of the earliest enterprises in china.
2rd generation –Eric Dong,is devoted to improving Dingxin’s products and processes and desires to build the company brick by brick,. The pioneering spirit lives on with product innovations featuring integrated solutions, ground-breaking material technology and added value for our customers.
Three main markets oriention of Dingxin:
• Northern China: Thanks to trust and confidence from our customers, Dingxin engages a attractive market share in North China over the last 30 years. Our products named as Dignxin delivers well-being and hotwater to two-thirds of all homes in the three north-east of provinces of china, with durable lifetime economy.
• OEM/EXPORT: We are proud to supply water heaters to various brands in the heating industry all over Europe,South America,South asia. OEM is an important part of our business because it inspires and motivates us to think innovatively, be flexible in our approach and challenge traditional mind-sets.
• Kitchen&bathroom branch: Dingxin focuses on the domestic market of kitchen&bathroom since 2016 and whose sales make up about 40% of the turnover and gives us a unique perspective and knowledge of related business lines and innovative marketing strategies which benefit all our customers.
DINGXIN story
One electric water heater branded as Dingxin, which has warmed Mr Chen for 22 years. In 1991,Mr Chen bought a new water heater and normally lived with it as long as 22 years in Wenzhou
Historic milestones
Dingxin launched a promise to replace the water heaters free of charge for those were purchased before 1995 and still normally used up to 2015. When Mr. Zhang saw this news,he immediately rushed to the Dingxin franchise shop of department store in Taiyuan city, Shanxi province. the Dingxin staff there offered Mr. Zhang for a free replacement service;
One electric water heater branded as Dingxin, which has warmed Mr Chen for 22 years. In 1991,Mr Chen bought a new water heater and normally lived with it as long as 22 years in Wenzhou .when Dingxin launched a campaign that every home could receive new water heater replacement installation service free of charge only if who purchased Dinxin water heaters before 1995 and still normally adopt it with over 22 years, Surely Mr Chen belongs to the ones who could received this fantastic service launched by Dingxin.
Mr. Zhu, in Dingxin franchise department, purchased two electric water heaters in 1988 and he spent ￥500 in all. When it comes to 2014, the two electric water heaters have been in its life time for 26 years and still have been in fantastic condition. The Dingxin promise to offer free replacement service of the two water heaters
In 1993, Mr. Wang purchased this water heater in franchise department of Tangshan city, Hebei province.and it is well in circulation for over 23 years, Dingxin offer free replacement service out of security considerations in 2015
Warranty Information
Dingxin warrants for 2 years from the date of purchase, that the Product will: i) conform to Dingxin approval specification, ii) be free from defects in materials and workmanship, subject to conditions below. All electric components carry a 2-year warranty
Scope
Dingxin warrants for 2 years from the date of purchase, that the Product will: i) conform to Dingxin approval specification, ii) be free from defects in materials and workmanship, subject to conditions below. All electric components carry a 2-year warranty.
The warranty is voluntarily extended by Dingxin to 5 years for the premium models. This extended warranty only applies to Products purchased by a consumer, that has been installed for private use and that has been distributed by Dingxin or by a distributor where the Products have been originally sold by Dingxin.
The extended warranty does not apply to Products purchased by commercial entities or for Products that have been installed for commercial use. These shall be subject only to the mandatory provisions of the law. The conditions and limitations set out below shall apply.
Warranty Information
Dingxin warrants for 2 years from the date of purchase, that the Product will: i) conform to Dingxin approval specification, ii) be free from defects in materials and workmanship, subject to conditions below. All electric components carry a 2-year warranty
Coverage
If a defect arises and a valid claim is received within the statutory warranty period, at its option and to the extent permitted by law, Dingxin shall either; i) repair the defect, or; ii) replace the product with a product that is identical or similar in function, or; iii) refund the purchase price.
Dingxin possess all property of any exchanged Product or component. Any valid claim or service does not extend the original warranty. The replacement received Product or part does not carry a new warranty.
Manufacturing
Excellent working condition & longer service life: no leakage, rust-free, high strength and strong resistance to corrosion
Tank comparison
COMPARISION BETWEEN SS TANK AND ENAMEL TANK
ENAMEL TANK
Porcelain Enamel Tank - is a trusted & proven technology for inner tank of water heaters. Used widely across the world, it is ideal for long life & trouble free performance in all kinds of water. More than 95% of water heaters produced worldwide are with enamel tanks. Corrosion protection is very good due to fusion of glass layer to metal.
SS TANK
Stainless Steel Tank - this is an outdated technology that manufacturers are moving out of now. Corrosion protection is very poor, particularly in hard water and due to poor welding quality.
SL Description Enamel Tank SS Tank
1 Protection Coating Porcelain Enamel -
2 Coating Type Inorganic None
3 Coating Thickness 250 - 400 microns None
4 Coating Adhesion Fused with metal None
5 Baking Temperature 850 deg C -
6 Life of the Coating Long life -
7 Usage Widely used Internationally Limited. In very few countries
8 Material Mild Steel Stainless Steel
9 Thickness 2.0mm 0.63
10 Rated Pressure 8kg/cm2 3kg/cm2 & 6kg/cm2
11 cathodic protection Magnesium Anode -
12 Hard water Suitability Good Poor
13 Corrosion Protection V.Good Poor-Average
14 Hot Water resistant V.Good V.Good
15 Approved Quality Standards BIS, IEC, DIN & UL BIS
HARD WATRT
As so common problem for millions of households across the country.Hard water means excessive dissolved minerals, specifically calcium and magnesium in tap water various in different countries.
Hard water is a negative impact because of much limescale it brings, Thus, in water heaters the heated hard water forms a scale of limescale deposits on the tank surface and reduces the heat conductivity of heaters sometimes even leading to its breakdown. and this contributes to inefficiency and costly electricity bill . Limescale has been known to increase energy bills by up to 25%.
Efficiency loss chart(limes scale thickness as variable)
Manufacturing
Excellent working condition & longer service life: no leakage, rust-free, high strength and strong resistance to corrosion
Water heater tank
Advantage of Enamel coating water tank:
1. Excellent working condition & longer service life: no leakage, rust-free, high strength and strong resistance to corrosion。
2. Clean energy and green product: no poisonous metal such as plumbum, hydrargyrum and chromium, bring health to your life。
3. Do good to heat preservation
1. Excellent working condition & longer service life
2. Clean energy and green product
3. Do good to heat preservation
Workmanship of enamel water tank:
1. High-strength low-carbon steel plate
2. Ultra-fine powder enamel layer
3. Blue high-temperature calcination coating
4. Three-layer strengthened protection
5. No deformation under 100,000 times impulse test
Downloads
Excellent working condition & longer service life: no leakage, rust-free, high strength and strong resistance to corrosion
Installation and manuals
Downloads
Excellent working condition & longer service life: no leakage, rust-free, high strength and strong resistance to corrosion
Product Catalogue
- How to know the quality of stainless steel electric heating element?
- What are the basic structures of stainless steel electric heating element?
- Let's Take A Look At The Inner Tank Material!
- Shell Materials of Electric Water Heaters: Cold-rolled Steel or Plastic？
- Copper heating element is not suitable for all water quality
Warranty Information
Dingxin warrants for 2 years from the date of purchase, that the Product will: i) conform to Dingxin approval specification, ii) be free from defects in materials and workmanship, subject to conditions below. All electric components carry a 2-year warranty
Conditions
The Product is manufactured to suit most household water supplies. However, there are certain water chemistries (outlined below) that can have a detrimental effect on the Product and its life expectancy. If there are uncertainties regarding water quality, the local water supply authority can supply the necessary data. The warranty applies only if the conditions set out below are met in full:
• The Product has been installed by a professional installer, in accordance with the instructions in the installation manual and all relevant Codes of Practice and Regulations in force at the time of installation.
• The Product has not been modified in any way, tampered with or subjected to misuse and no factory fitted parts have been removed for unauthorized.
• Any disinfection has been carried out without affecting the Product in any way whatsoever. The Product shall be isolated from any system chlorination.
• The Product has been in regular use from the date of installation. If the Product is not intended to be used for 60 days or more, it must be drained.
• Service and/or repair shall be done according to the installation manual and all relevant codes of practice. Any replacement parts used shall be original DINGXIN i spare parts.
• Any third-party costs associated with any claim has been authorized in advance by DINGXIN in writing.
• The purchase invoice and/or installation invoice, a water sample as well as the defective product is made available to DINGXIN i upon request.
• Failure to follow these instructions and conditions may result in product failure, and water escaping from the Product.
Warranty Information
Dingxin warrants for 2 years from the date of purchase, that the Product will: i) conform to Dingxin approval specification, ii) be free from defects in materials and workmanship, subject to conditions below. All electric components carry a 2-year warranty
Limitations
The warranty does not cover:
• Any fault or costs arising from incorrect installation, incorrect application, lack of regular maintenance in accordance with the installation manual, neglect, accidental or malicious damage, misuse, any alteration, tampering or repair carried out by a non-professional, any fault arising from the tampering with or removal of any factory fitted safety components or measures.
• Any consequential damage or any indirect loss caused by any failure or malfunction of the Product whatsoever.
• Any pipework or any equipment connected to the Product.
• The effects of frost, lightning, voltage variation, lack of water, dry boiling, excess pressure or chlorination procedures.
• The effects of stagnant (de-aerated) water if the Product has been left unused for more than 60 days consecutively.
• Damage caused during transportation. Buyer shall give the carrier notice of such damage.
• Costs arising if the Product is not immediately accessible for servicing.
These warranties do not affect the Buyer’s statutory rights.
FAQ
Q1:How long does the order take?
A:Sample order will be finished within 15 days while normal order will be finished within 25-30 days after receiving deposit,
Q2:What are my WARRANTY OPTIONS on the water heaters you sell?
Dingxin Water Heater Company provides a basic, standard warranty. Our basic warranty is one year for full units or 1% spare parts service.
Q3:Do you accept OEM or ODM orders?
A:Yes, Our R&D team will offer one stop service for you from original idea to finished product.
Q4:What’s the MOQ?
A: Normally MOQ is 1*20 ft container(trial order's quantity is negotiable)
Q5:How can I visit your factory?
A: Sure,Our factory is located in Shaoxing Shengzhou, China, near to Hangzhou Airport and Ningbo Airport .You are always welcome to visit us! We will offer pick up service and free accomodation.
Q6:When can I get the price?
A:Within 24 hours after we get your inquiry.
Q7:Can you offer sample for quality check before order ?
A:Yes , we provide sample service before mass order.
Q8: what other size water heater you have ?
A: We have storage models of 8L\10L\15L\30L\50L\60L\80L\100L\120L\150L,and besides storage model,we also work on instant models,and gas models.
Q9: Can the price be cheaper?
A: Price always follows its quality and we will offer truthful opinion on the marketing strategy on pricing and quality orientation.
Q10: What payment terms?
A: T/T; L/C,West Union or other payment term negotiable