Casting 304 stainless steel and plate 304 stainless steel, although the chemical composition is similar (all in line with the 304 stainless steel Cr, Ni content standards), but due to the different production processes, the two microstructure, mechanical properties and application scenarios there are significant differences.

The following is a comparative analysis from the process, performance, advantages and disadvantages and application scenarios:

First,A core difference 

Two, Advantages and Disadvantages of Casting 304 Stainless Steel

 Advantages

1. Complex Shape Adaptability: Suitable for the production of parts with internal cavities, curved surfaces, or shaped structures (e.g., pipeline joints, impellers).

2. High material utilization: near-net shaping reduces cutting and is suitable for the economical use of high-cost alloys.

3. Batch Cost Advantage: lower cost than plate machining when producing complex parts in small batches.

Disadvantages

1. Lower mechanical properties: casting defects (porosity, shrinkage) lead to lower tensile strength and fatigue life.

2. Fluctuating corrosion resistance: internal defects may become corrosion initiation points, higher risk for long-term use.

3. Surface treatment needs: Post-treatment such as sandblasting and machining are required to meet the usage requirements.

Three, Plate 304 stainless steel advantages and disadvantages

 Advantages

1. Excellent mechanical properties: rolling process refines the grain, tensile strength, elongation are better than castings.

2. Stable corrosion resistance: Dense structure reduces the risk of localized corrosion, suitable for harsh environments (e.g. chemical equipment).

3. Good surface quality: can be directly used for exterior parts (e.g. elevator decorative panels, food equipment surfaces).

 Disadvantages

1. Shape limitation: only suitable for flat plate or simple press molding, complex structures need welding/splicing.

2. High processing cost: complex parts require multiple stamping and cutting processes, more material waste.

3. Anisotropy: Cold rolled sheet may have directional mechanical differences (need to pay attention to rolling direction design).

Four, key material selection recommendations

1. Preferred casting 304 scenarios:

- Complex structural parts (e.g., pump housing, valve body).

- Small batch customized production.

- Non-load-bearing parts that do not require high surface finish.

2. Preferred Scenarios for Plate 304:

- Load-bearing structural parts (e.g., reactor tank shells, building curtain wall skeletons).

- Environments with high corrosion resistance requirements (e.g. marine equipment, food processing lines).

- Parts requiring welding or deep-drawn molding (e.g., storage tanks, piping).

Five. ADDITIONAL INSTRUCTIONS

- Compositional differences: Casting 304 may be adjusted for trace elements (e.g., increase Si content to 1.5% to improve flow), check specific standards (e.g., ASTM A743/A744).

- Heat treatment effects: cast parts usually require solution treatment (water quenching at 1050-1100°C) to eliminate segregation, while cold rolled sheets may recover plasticity by annealing.

- Economic Comparison: Plate is preferred for large quantities of simple parts, and casting costs are significantly lower for complex parts with single piece weights >50kg.

Casting stainless steel submersible pumps are widely used in industry, agriculture, sewage treatment and other fields due to its material properties and process advantages. The following are its core advantages and specific analysis:

I. Summary of core advantages

Integrated molding of complex structures

Excellent corrosion resistance

Strong impact and wear resistance

Lightweight and high sealing

Adaptation to harsh environments

Low maintenance costs

II. Analysis of specific advantages

1. Integrated molding of complex structures to enhance reliability

Advantages of casting process:

Complex structures such as impellers, pump casings, and deflector shrouds can be molded in one go through precision casting (e.g., lost wax casting) to avoid welding or splicing defects (such as weld corrosion and stress). Avoid welding or splicing defects (e.g. weld corrosion, stress cracking).

Application Scenario:

Suitable for high-precision flow channel design (such as spiral impeller, multi-stage pump body), reducing fluid resistance and improving pumping efficiency by 10%-15%.

2. Excellent corrosion resistance, adapt to diverse media

Material properties:

304/316 cast stainless steel containing Cr (18%-20%), Ni (8%-12%), the surface of the formation of a dense oxidized film, resistance to seawater, acidic and alkaline solutions, chlorinated wastewater and other corrosive media.

Comparison advantage:

Compared with cast iron pumps (easy to rust), plastic pumps (poor temperature resistance), cast stainless steel pumps in the pH 2-12, temperature ≤ 80 ℃ environment life extension of 3-5 times.

3. Strong impact and abrasion resistance, suitable for particle-containing media

Structural Strengthening:

The casting process can improve the hardness (HRC 25-30) by adjusting the carbon content (0.03%-0.08%) and heat treatment (solution + aging), which is resistant to the impact of particles such as gravel and slag.

Case data:

In sewage treatment scenarios, the impeller wear rate of cast stainless steel submersible pumps is 40%-60% lower than that of ordinary cast iron pumps.

4. Lightweight design, reduce energy consumption and installation difficulties

Density comparison:

Stainless steel density (7.9g/cm³) is lower than cast iron (7.25g/cm³), but the casting can be realized through the thin-wall design (minimum wall thickness of 3-5mm) to achieve lightweight, the weight of the whole machine to reduce 15-20%.

Sealing improvement:

One-piece casting reduces seams, combined with mechanical seals (e.g., silicon carbide sealing ring), the risk of leakage is reduced to **<0.1ml>

5. Adapt to harsh environments, high stability

Temperature resistance:

short-term resistance to high temperatures of 120 ℃ (such as hot water circulation pumps), low-temperature environments (-20 ℃) still maintain the toughness, without the risk of brittle cracking.

Pollution resistance:

fully enclosed structure (IP68 protection level) can be submerged in sewage and sludge for a long time to run, the motor cavity adopts double sealing, excellent water seepage prevention performance.

6. Low maintenance cost, long service life

Ageing resistance:

No risk of coating peeling (compared with galvanized pumps), long-term immersion is not easy to occur pitting or intergranular corrosion, the design life of up to 15-20 years.

Ease of maintenance:

Modular design (e.g. removable impeller) supports quick replacement of wear parts, reducing maintenance time by more than 50%.