Hello, could someone please tell me the difference and advantage of this 3 molds, I understand this are also the most used types in the Chinese market right now?!

I really would appreciate every comment! Thanks, Jonathan!

Hi Jonathan,

there is not a big difference between the 718H and the P20H.
Both is only could used to the standard plastic material moulds which is not agressive and not much filler inside.
The S136H has good corrosion resistance and could used for agressive materials. (after heat treatment)
But we are spoken about China, than you have to pay more attention about the source of these steels. In my experience is that there is very limited source in China which could guarantee the quality of this steel. (mainly only from import source)

Regards: Zoltan

Hi Bro, I do not agree with Zoltan, I think he is not a professional at least not a tool guy, As far as I know, all these three types are pre-harden steel, no more heat treatment. (718H&P20H---HB 330-370, S136H--HB 290-330), 718H is a improved steel based on P20H, both are common used in plastic and die tools, while S136 is a high purity, high optical finishing, anti-corrosion steel, usually used for high polishing, like clear part, Lens, etc.
These steel are easily available from our like ASSAB suppliers, and steel certification can be supplied.

Thanks

Haijun

Hello, thanks a lot for your answers- but this exactly is my problem. I've heard too many different opinions from different sides! And no reliable information on internet.

What I've also heard recently is that P20H is mostly used in US, S136H German and so on.


I've also received another interesting email today, so I just post it here: "718 is one steel material of P20 steel. 718H is harden based on 718. So 718H is also one steel material of P20, just was harden. P20 have both domestic and imported in China.

S136H is better than P20H(718H), it have much stronger corrosion resistance, and more hard. The shot life of S136H mold is much longer than P20H, and that can make the part surface be more nice."

...any other opinion?

Hi Jonathan, and Haijun,

First of all please check the technical information on the ASSAB site and you will agree with my when I mentioned you only could can rely on the Quality if it is imported.
Because if you check thier product under this names you can find the Uddeholm grades from Sweden. (imports)
But you can check it in the internet in different standards like P20=1.2311; 718= 1.2738; S136=Stavax.
If you check the datasheet of the supplier like Uddeholm you will see there is not much difference between the P20 and the 718. Here you can see also information about the heat treatments, machining too. (also for the S136, Stavax)
But the question is how you can be sure what you have ordered and recieved is the same?
This is the challange I thing you are facing now. I'm right?
But also if you are searcing in the internet you can find several comperison table between the different standards and this will help you to find more technical information.

To get the specifics for each you should refer to the DIN standards for each. But, generally speaking P20 (1.2311/1.2312) has been used for years as cavity/core material in injection molds for short to medium life expectancy- up to a few 100,000 shots-pre hardened, HRC 28-32- machinable with normal cutting tools. 718/718HH (1.2738) similar to P20 but slightly harder--up to around HRC38- still machinable with normal cutting tools, longer life expectancy but not subject to brittle fractures like hardened tool steels. S136 is a variation or modified Stainless Steel similar to 420SS with a hardness of around HRC50-52. Much more time consuming to machine and more costly to process than 1.2312 or 1.1738, but will have an extended lifetime and is corrosion resistant. Especially good for for hi gloss requirements and longer life tools where you are using abrasive materials or have poor water conditions which will corrode the waterlines in 1.2312 or 1.2738 quite readily.

Hello sir,We are traders of tool & alloy steels, Kindly suggest the best mould steel co. in china.

if we order the molds for 718H/718 material how can we assure or terst after mold is ready for trial ? is there any laboratory in china ? or what is process ? please response immediate.

Hi Jonathan and Zoltan,
I have a better answer for How you will asure that what you order and received? ??
S136 is plastic mold steel comes under stainless steel family, which having very good corrosion resistant and polishability and in China it is supplied by ASSAB.
ASSAB ( Associative Swedish steel AB)company is importing material from steel mill based in Sweden called as UDDEHOLM.
As per Uddeholm std. This grade name is Stavax ESR. For this you will get Uddeholm mill TC from Assab China.

Is S136 Heat treated again

Is S136 Heat treated again after machining

IF WE ARE USING CHINA P-20 FOR CORE AND CAVITY IS THERE ANY PROBLEM IN THAT..........?

dear friend

hello i need to make rubber mould wich material is better

p20 718

thank you

sir, mu question is the difference between H13 AND S136 STEEL AND WHICH IS BETTER STEEL TO FORM MEDICAL DEVICE LIKE TEST TUBE MOULDS

I am quoting a mould in china and they quoted S136 with HRC 58-52 , warranty 1 million shots. Is it ok ? I will appreciate your comments

I have few molds which make it for home appliance products. And the resin of the product is PA66 GF30 King Fa.

The steel material required by customer is "hardened steel". It is "hardened steel", not a pre-hardened steel.

Unfortunately, I don't have any experience for designing this type of molds.

Hereby, I would like to get everyone's advise for designing the mold. E.g:.
1) What we need to consider during design the mold?
2) What is the tolerance that we need to consider?
3) What we can do & what we can't do?

If anyone of you has the guidelines, please don't mind to share.

If thermal expense coefficient affect the dimension wile heating, the mold is suddenly cooling after the injection process may cricking the mold.

Hey Guys,

I'm currently asking for a mold with 32 cavities for small PVC parts.

I've been given different quotations with three types of steel for core and cavities.

S136, 2344 steel and P20.

Could you tell me which is the most suitable for my mold?

Thanks!

Hello
Please I need a help.We need to produce rubber mould please which material is better for mold

We make our glasses frame from pc material. So if we use S-136 for our mould how would it be different from the normal mould that we use?

The steel quality of the molding components has a direct influence on mold quality and service life, and determines the appearance and quality of a plastic injection molded product, so plastic injection mold making factory must make careful selection. Generally speaking, materials have to be selected based on contract stipulations, client requests, as well as product / mold requirements and characteristics.

Principle for steel selection of molding components: different types of steels need to be selected based on types of plastic, product shapes / dimensions, product appearance / quality / application requirements and production scale, etc., while paying attention to the various material performances like machining, polishing, welding, texturing, deflection and abrasion resistance, and at the same time taking economy and mold manufacturing conditions/process into consideration.

With regard to the plastic molds for production of transparent plastic parts, the mold cavity and core need to select high-grade imported steel materials that boast an outstanding mirror polishing performance, such as 718 (P20+Ni), NAK80 (P21), S136 (420) and H13 steels, among which, 718 and NAK80 are pre-hardened, so preheat is not necessary; S136 and H13 steels are annealed usually with a hardness between HB160 and 200, so vacuumquenching and tempering are needed after rough machining; the hardness of S136 steels is usually between HRC40 and 50, while that of H13 steels is between HRC45 and 55.

With regard to the molds for production of products that have high requirements on surface quality, long service life and large production scale, the material selection for the molding components should be made according to:

a) The mold cavity needs to select high-grade imported plastic injection mold steel materials that boast an outstanding mirror polishing performance, such as 718 (P20+Ni), NAK80 (P21) which are pre-hardened, so preheat is not necessary.

b) The mold core may select medium-/low-grade imported P20 or P20+Ni steel materials, such as 618, 738, 2738, 638 and 318 which are all pre-hardened; for molds that are in small-scale production, domestically produced mold steels or high quality imported carbon steels like S50C and S55C can be used.

With regard to the molds for production of average surface quality products, the molding components may select the following steel materials:

a) The mold cavity and mold core of small-sized precision molds may select medium-grade imported steel materials, such as P20 or P20+Ni steels.

b) For medium and large-sized molds, when the molding steel do not have special requirements on steels, the mold cavity may select medium-/low-grade imported P20 or P20+Ni steel materials; while the mold core may select low-grade imported P20 steels or high quality imported carbon steels like S50C and S55C.

c) For textured cavities, try to avoid the application of the P20+Ni steel with the no. of 2738 (738) when producing matt texture.

With regard to internal parts that do not have requirements on surface quality, when molding materials do not have special requirements on mold steels, the mold cavity may select low-grade imported P20 or P20+Ni steels, or the high quality imported carbon steels like S50C and S55C, or the domestically produced plastic mold steels; and the mold core may select high quality imported/domestic carbon steels.

For corrosive plastic materials which contain fluorine or chlorine, or the plastic materials that contain various additives like flame retardants, the mold may select imported corrosion resistant steels when the product needs to be manufactured to high requirements, or select domestically produced corrosion resistant steels in case of general requirements.

If the plastic materials produce a strong abrasion or impact effect on mold steel, for example nylon + glass fiber, the mold needs to select imported or domestically produced H13 steels which are highly abrasion/heat/stretch resistant and highly resilient.

For insert molding, the mold may select the same material as the insert. For the mold part that is hard to cool or has high requirements on cooling, the insert materials should choose be-bronze or aluminum alloy.

For the moving parts in a mold, which are involved in molding, the material should be selected according to:

Imported high-grade high-polishing steels, like 718 and NAK80, should be selected for production of plastic products.

Usually, medium-grade imported steel materials with a high hardness and a high strength should be selected for opaque products, such as 618, 738, 2738, 638 and 318, etc., of which the surface should be nitrided with a depth of 0.15 – 0.2mm and a hardness of HV700 – 900.

If the mold has a low requirement, low-grade imported or domestic plastic injection mold steel materials can be selected, which is usually nitrided with a hardness of HV600 – 800.