Selection skills of quenching medium in heat treatment of fasteners

Fasteners are widely used in machinery, automobiles, aviation, aerospace, construction, transportation, communications, electronic appliances and many other industries. Various industries have different requirements for fasteners, including different comprehensive mechanical properties. . The comprehensive mechanical properties of fasteners are mainly determined by the selected materials and heat treatment quality, so it is imperative to select materials strictly and reasonably and improve the level and quality of heat treatment.
Heat treatment is divided into two processes, heating and cooling, and the ideal heat treatment quality can be obtained by scientifically controlling the two processes. Reasonable selection and scientific use of quenching medium is the essence of controlling the cooling process.

1. Bolts, studs, screws, nuts and special-shaped non-standard parts mainly based on ML35 (32, 40) etc. Due to the problem of material hardenability, the quenching medium with faster cooling speed should be used in the heat treatment process of this kind of parts , So as to meet the requirements of the hardness, metallography and mechanical properties of parts quenching.

I. The product size is M4-Ml 6, you can choose 3-5% KR6480 polymer water-soluble quenching agent, if you choose 35#, 35A, 35S can be relaxed to M18–M20.

II. The product size is M10~M24, you can choose 8~10% KR7280 water-soluble quenching agent.

III. If the product size is larger than M24, you can choose 10-15% KR7280 water-soluble quenching agent.

IV, the product is mainly 45#, you can choose KR6480 or KR7280 according to the size of your product.

2. Bolts, bolts, screws, nuts and special-shaped non-standard parts based on 35CrMo, 40Cr, 20MnTiB, 35VB, etc.

I. If your product is mainly 35CrMo, 40Cr, you can choose KRll8 quick quenching oil or 5-10% KR6480 polymer water-soluble quenching agent.

Ⅱ. If your products are mainly 20MnTiB and 35VB, you can choose KR7280 or KR6480.

3. Shallow carburized self-tapping screws and pins based on low-carbon steel 10#, 15#, 20#, 20Cr, 1018, 1022, 10B21, etc. can be selected as KR6480 or KRll8

4. Spring washers and retaining rings mainly made of 65Mn, 60Si2Mn, 70, etc. can be selected with KRl18 quick quenching oil.

5. There are many types of products, and KRll8 or KR6480 (which can meet the quenching and carburizing and quenching of all alloy steels and carbon steels of a certain size) can be selected for larger size spans. The internal quality of the workpiece depends on the heat treatment quality. Quenching medium plays a decisive role in heat treatment, but it is the smallest piece of heat treatment production cost. As long as you pay a little attention to the quenching medium and choose professional and reliable products, you can enjoy professional consultation, after-sales service, and To achieve unexpected results, and greatly reduce the overall production cost.


1. KR6480 is a highly versatile water-soluble quenching agent

2. KR7280 is currently the world’s fastest cooling water-soluble quenching agent and is widely used in Europe.