1. No Invasive Corrosion after Washing When Rust Appeared for 5,000 Hours after SST.
2. No intergranular Corrosion after High-Frequency Induction Hardening.
3. Suitable for High Tensile Steel Plates and Extreme Climate.
4. Zinc Plated Surface Protecting inner Holes of Mating Parts.
Lots people often misapply salt spray test (SST) and Kesternich test for carbon screw to stainless steel or Bi-Metal products. The testing difference between carbon steel and stainless steel lies in – the testing of carbon steel is usually conducted until the sign of rust is noticed, while the testing of stainless steel is only accurate with the steel observation even after the sigh of rust is shown. The testing of stainless steel is commonly done in two ways: one is corrosion speed test, and the other is chromium carbide and chromium nitride (intergranular corrosion) test. The most vital part of these is to observe whether the surface of the steel still maintains the resistant to invasive corrosion after washing even when rust has appeared for 5,000 hours after SST or after 35 cycles of Kesternich test. Our new Bi-Metal screws can meet the criterial
Generally speaking, there are two heat treatment processes for Bi-Metal screw. One is high-frequency induction hardening and the other is continuous heat treatment furnace. The former costs higher but ensures the stainless steel does no break; the latter costs lower, but it has an intergranular corrosion problem. We adopted the more costly one, enabling the Bi-Metal screw to retain the original properties of stainless steel and avoiding the disturbing intergranular corrosion cause by chromium carbide and chromium nitride.
Bi-Metal screw made of low carbon and low alloy steel cant be easily tapped into high tensile steel plates applies to environment that are prone to typhoons, extreme cold, and earthquakes. By comparison, Our Bi-Metal screw made of SCM435 showcase their exceptional stability when tapped into high tensile steel plates. “Environment that contains chlorine such as seaside, swimming pool, and water plant are advised to use A4 stainless steel that is resistant to chlorine. A2 stainless steel that does not contain molybdenum is only suitable for common environment, for it is non-resistant to chlorine. The superior performance of the new Bi-Metal screws released by us is proven to function well even in the environment below -40ºC. The screws are the only material that can still function normally in such a harsh environment.
Nearly 99% of the Bi-Metal products in the current Asia Market utilize Ruspert treatment. However, Ruspert treatment is unable to protect inner holes of the mating parts, so we insisted on applying zinc plating to their Bi-Metal screws. Coating on the Bi-Metal products, in fact, does not improve the weather ability, whereas the zinc plating can protect the surrounding iron, so as to prolong the durability of inner holes for 10 more years.
|Technical Delivery Conditions|
|General requirements||As specified in DIN 267 part 1|
|Screw thread and thread ends||As specified in DIN 7970|
|Cross recesses||As specified in DIN 7962|
|As specified in DIN 267 part 12|
|Product grade A as specified in ISO 4759 part 1|
|ISO 4759 Part 1|
|Surface finish||As processed||Bright|
|DIN267 Part 2 shall apply with regard to surface roughness|
|DIN267 Part 19 shall apply with regard to permissible surface discontinuities|
|DIN267 Part 9 shall apply with regard to electropiating|
|Other type of surface protaction being suject to agreement|
|Acceptance inspection||DIN267 Part 5 shall apply with regard to acceptance inspection|
Who is Lockey?
A fastener manufacture founded in 1973. Dragon Iron Group devotes itself to the manufacture and sales of fasteners, hardware parts, forging and machine parts for Auto and other industries.
Dragon Group has its headquarter, Dragon Iron Enterprise, in A Lien, Taiwan.
Lockey Industrial Co., Ltd. set up in 2003 in Dongguan City to be the Foreign Sales Department of the group. Our plant was established in Jingjiang City. In that way, we can easily export our products .
What do Lockey produce?
As a fastener manufacture, we mainly produce including, but not only:
1. Bolt, studs, and thread rods…
2. Hex nut, nylon nut, flange locknut…
3. Tapping screw, drilling screw, wood screw, machine screw, socket cap screw…
4. Plain washer, spring washer, tooth washer…
5. Structural applications, ASTM A325/A490, ASTM F1852/2280, DIN6914/5/6, DIN7990…
Meanwhile, special fasteners, hardware parts, forging and machine parts for Auto are also in our range. We make parts for Toyota, Honda.
70% of our products are exported.
Lockey never stops doing one thing: INNOVATE. Innovation is the permanent power for the development of Lockey. Technology innovation and concept innovation, keep Lockey going well and going further. Meanwhile, Lockey gathered a group of talents who good at management and co-operation. Go and contact with these professional man, you will get a satisfied result.
We are glad that you choose Lockey as your supplier, but Lockey more than a supplier. We are partner. We do not only sell, we share. Share the newly info of fastener, price trend…we also share profit.
We are friend. We do not only care our sales, but also yours; and the quality in using.
What do Lockey do to assure the quality?
As a over 40 years experience in fastener manufacture with ISO9001 certificate, we meet difficulties or problems, and we solve them all ways. Lockey set up a quality assurance system according to ISO9001 with the 40 years experience. Criteria were made on factors that may effect the quality. 80% of our staff are skilled, and have worked in Lockey for more than 5 years, employee have to take skill class on/off work for weeks. All of these is to guide our worker how to prevent and handle an issue.
Do Lockey produce non-standard item?
Yes, we do. Send your specification drawings to our sales representative, then you will get a quotation.
Do lockey have a published price list?
We do NOT have a published price list. In our business market conditions are always fluctuating, which makes standard pricing difficult to maintain. We allow our sales staff to be flexible when it comes to quoting on your requirements, which means that you will receive the best pricing available when you need it.
Do Lockey offer a discount?
Of course. we can offer you a discount base on your large quantity. But at the same time, like what we said above, we believe our sales staff have offered you the best price. In that way, you may have a discount, but not a big one. Go and explore for it.
Do Lockey provide samples?
Why not, and stored samples are totally free. What we are going to tell you is that we do NOT have budget for Express.
Whats the delivery time?
It depends on your order quantity. It is about 20-40 days for standard ones, 35-60 days for non-standard ones. Check it with sales representative, he/she will give a accurate date of shipment.
What is the payment term?
T/T & L/C are the prefer payment term. Also Western-Union is acceptable for low value payment, like samples Express fee.