Stainless Steel Casting

What is Stainless Steel Casting?

Stainless steel casting is a metal working process to produce custom stainless steel parts. It works by pouring melton stainless steel into molds for solidification, thus achieving a solid stainless steel component in a desired shape.

Compared with other processes, stainless steel casting can create complex components with fine detail and good dimensional accuracy, which reduces or eliminates post-machining operations. It is also a great alternative to the welding fabrication process, as several stainless steel parts can be cast in one piece, which saves time and cost for additional welding or assembly.

Stainless steel casting is used where both the properties of steel and corrosion resistance are required. Like other cast steel alloys, stainless steel is one of the most commonly used materials in casting production.

Common Material Grades of Stainless Steel Casting

304 The most widely used austenite steel, may be referred to as A2 stainless.
304L This grade has slightly lower mechanical properties than the standard 304 grade, but is still widely used in casting for its versatility
316 The second most common austenite steel, also referred to as A4 stainless. SS316 primarily serves to enhance resistance to corrosion.
316L Lower carbon content than 316 stainless steel, which reduces the sensitization effect caused by the high temperatures involved in welding. Besides, it shows better resistance to stress-corrosion cracking.
17-4 PH Most common precipitation-hardening martensitic stainless steel, which uses about 17% chromium and 4% nickel.
2205 Duplex Used for its good mechanical properties and excellent corrosion resistance properties.

More information on Stainless Steel Casting Types and Grades …

Stainless Steel Casting Process

CFS Foundry mainly produces stainless steel castings in the investment casting process, which is also known as the lost wax casting process.

Stainless steel casting process involves melting of metal, molding, and creating quality components with constant heating or cleaning. When normal casting components are not able to deliver enough strength and shock resistant features, then stainless steel castings are just taken wonderful choice over others. This process can produce high precision net shape castings with no machining. Normally we can control such precision stainless steel casting with tolerance CT5-6 level. Another advantage is that, with this process, our foundry can supply stainless steel casting with no defects.

ISO8062(GB/T6414) CT5-CT6
Linear Dimensional Tolerance (mm)
0 10  0.36 ±0.18 0.52 ±0.26
10 16 0.38  ±0.19  0.54 ±0.27
16 25  0.42 ±0.21 0.58  ±0.29
25 40  0.46 ±0.23 0.64 ±0.32
40 63  0.5 ±0.25 0.7 ±0.35
63 100 0.56 ±0.28 0.78 ±0.39
100 160 0.62 ±0.31 0.88 ±0.44
160 250 0.7 ±0.35  1 ±0.5
250 400 0.78 ±0.39 1.1 ±0.55
400 630 0.9 ±0.45 1.2 ±0.6

Post Treatments of Stainless Steel Casting

Post Machining

Although stainless steel investment castings can achieve a higher size accuracy and surface finish, it does not mean machining can be saved for all the stainless steel cast products. Machining will have to be performed when there is a closer tolerance and surface finish requirement that casting can not reach.

CFS foundry has built a reputation to do machining after stainless steel casting. Our specialized machining services enables us to manufacture stainless steel castings with intricate geometry and detail, while maintaining high precision and accuracy. Our company has equiped with full sets of machining equipmement from manual turning & milling to complex CNC machining services. We offer the capabilities to machine stainless steel castings from several ounces up to 100lbs.

Inspection after machining is also very critical, we utilize manual inspection equipment and gages as well as the latest in coordinate measuring machine (CMM) technology to measure and record all the dimensions. This ensures our customers always get the quality they want.

Surface Finishing of Stainless Steel Casting

Surface treatment or surface finish is very popular post treatment method to smooth or brighten the surface of stainless steel castings. See the types of surface finishes for stainless steel castings in below:

Type Introduction
Pickling & Passivation Pickling is a chemical treatment way to eliminate surface dirts like oxide skin, rust, welding spots, etc. And passivation is a process that forming a new abundant chromium protective layer, thus to improve the anti-oxidation ability of stainless steel castings.
Shot Blasting The most widely used surface treatment method used to clean, strengthen (peen) or polish the surface of stainless steel castings. Low cost.
Glass Bead Blasting Glass bead blasting method to refine the surface of stainless steel castings. The surface smooth of sand glass bead blasting looks better than that of shot blasting, but higher cost.
Electropolishing Used to remove surface tiny burrs and improve the brightness of stainless steel castings.
Mirror Polishing The brightest surface polishing way that can achieve a very smooth and shining surface like a mirror finish. Only suitable for outside areas of stainless steel castings.
Vibratory Polishing A type of surface treatment process used to deburr, descale, clean, and brighten stainless steel castings. The surface looks smooth and a bit shining, but less brightness than mirror polished surface.

Stainless Steel Casting Applications

For the unique physical properties of stainless steel, Stainless steel castings are served for a wide range of industries, especially those in severe environments. Below are the main applications of stainless steel casting:

Stainless Steel Casting for Food Machinery Parts

Almost all the food processing equipments are made in stainless steel due to its rust prevention capability. Such food processing equipments are normally assembled by many stainless steel components. There are several processing processes to produce these stainless steel components, such as casting, forging, welding, machining from plate, ect. Among them, casting is the most flexible manufacturing process to produce complex shaped components for food processing machinery. So stainless steel casting is widely used for food machinery application! Typical food machinery components made in stainless steel casting process are: metal grinder components, coffee machine components, etc.

Stainless Steel Casting for Valve & Pump Parts

Stainless steel casting is the most widely used technique for valve & pump components. For its complicated design of valve and pump components, stainless steel casting is able to produce any complex shape. Valve and pump components from stainless steel casting are durable enough for severe service applications. So stainless steel casting is a cost efficient way and a popular selection for pump and valve applications. Common valve & pump components made from stainless steel casting are : valve body, valve disc, valve bonnet, valve gland, pump body, pump impeller, etc.

Stainless Steel Casting for Marine Application

Stainless steel casting are used in marine applications which require parts that are strong with extremely high resistance to heat, abrasion and corrosion. CFS foundry uses a wide range of stainless steel alloys for recreational, governmental and commercial marine components. Stainless steel marine castings can be polished to a mirror finish for maximum corrosion and abrasion resistance.

New marine grade stainless steel investment castings for marine application could be supplied electro polished and machined from our company, saving our customers 30% on their current spend.

Stainless Steel Casting for Pipe Fittings

Pipe Fittings are components used for connecting, terminating, controlling flow, and changing the direction of piping in many different industries. When purchasing pipe fittings, considering the application, these pipe fittings are normally made of stainless steel 316, which is higher strength and more corrosion resistant than stainless steel 304. Stainless steel casting is the most cost effective method for small volume production.

Usually produced stainless steel cast fittings are elbow, tee, bushing, close nipple, etc. Our machining capability can meet any machining requirement like threads.

Stainless Steel Casting for Medical Parts

Stainless steel casting is able to produce a wide range of components for medical application. We work with numerous of stainless steel materials, including stainless steel 304(L), stainless steel 316(L) and more, to create custom parts that meet the tight tolerances and dimensional precision required by medical application. Stainless steel cast parts we manufacture for medical OEMs are included in: dental & surgical tools, Implantable components, operating tables & other operating room equipment, MRI machines, X-ray equipment, stretchers, wheelchairs & similar products, injury stabilizing devices, and more.


Other Applications of Stainless Steel Castings are: Sculpture parts, Bathroom & Toilet fittings, Door & Windows, etc.

Top Stainless Steel Casting Company in China

Top Stainless Steel Casting Company in China

CFS Stainless Steel Foundry is one of the leading stainless steel precision casting companies in China. We can manufacture custom stainless steel investment castings that match your exact design specifications. For parts ranging from 50g to 50kg or more, we provide tight tolerances and consistent part to part repeatability.

Our design & production capabilities include:

  • Intricate, near-net shape parts without secondary machining
  • Easily convert multiple parts into single assemblies
  • Thin walls for weight reduction opportunities
  • Surface finish of Ra6.3 or even better
  • Linear tolerances within CT4-CT6
  • Highly complex dimensional geometry
  • High precision machinability

Our mature casting technique makes us the most reliable one-stop source for stainless steel castings. The competitive prices and full services of stainless steel castings are the most attractive factors for foreign companies from the USA, UK, Canada, Australia, etc, to purchase products from our company in China.

Need stainless steel casting service in China? Contact us now!