In industrial piping systems, ball valves are widely used for fluid shut-off and isolation due to their simple construction, quick operation, and straight-through flow path. In particular, for systems requiring corrosion-resistant materials and operation under relatively high pressure and temperature conditions, stainless steel 3-piece ball valves are one of the commonly considered solutions.

The AUTOMA Stainless Steel 3-Piece Ball Valve AT300/AT301 features a Full Bore design, an Investment Casting body, a Blow-out-proof Stem, and R-PTFE valve seats. The product is available in sizes from 1/4″ to 4″, making it suitable for various industrial piping configurations.

AUTOMA AT300 and AT301 share the same 3-piece body design but differ in their primary materials. AT300 uses A351 Gr.CF8 and SS304, while AT301 uses A351 Gr.CF8M and SS316, allowing users to select the appropriate configuration according to the requirements of each system.

1. Overview of AUTOMA AT300/AT301 Stainless Steel 3-Piece Ball Valve

1.1. Introduction to AUTOMA

AUTOMA International Co., Ltd. is a Korean brand supplying industrial valves for various fluid control and shut-off applications in piping systems.

The AUTOMA Stainless Steel 3-Piece Ball Valve series is developed with a 3-piece body, Full Bore design, and multiple material options, making it suitable for systems requiring a robust ball valve for industrial operation.

Two representative models in this product series are:

• AUTOMA AT300
• AUTOMA AT301

The main difference between the two models is the stainless steel material used for the body, ball, and stem.

1.2. What Is an AUTOMA Stainless Steel 3-Piece Ball Valve?

The AUTOMA stainless steel 3-piece ball valve is a Ball Valve that uses a spherical ball with a through-hole to control fluid flow.

When the handle is rotated 90°, the ball opening can be aligned with the pipeline to open the valve or rotated perpendicular to the pipeline to close the valve.

The 3-Piece Body consists of a central body and two end connection sections, which are assembled using bolts. This construction facilitates disassembly of the valve assembly for inspection or maintenance.

1.3. Key Features of the AT300/AT301 Series

Key features of the AUTOMA AT300/AT301 ball valves include:

• Full Bore design.
• 3-piece body construction.
• Body manufactured using Investment Casting technology.
• Blow-out-proof Stem for enhanced stem safety.
• R-PTFE valve seats.
• Handle equipped with a Locking Device.
• Working pressure up to 1000 PSI W.O.G.
• Working temperature up to 180°C.
• Pipe thread according to ISO 228 BSPP (G).
• Connection options including NPT, BSPT, and Butt-weld.
• Sizes from 1/4″ to 4″.

1.4. Applications in Industrial Piping Systems

With its stainless steel construction, Full Bore design, and operating capability under relatively high pressure and temperature conditions according to the product specifications, AUTOMA AT300/AT301 can be considered for piping systems requiring fluid shut-off applications.

Typical application groups may include:

• Industrial piping systems.
• Water systems.
• Water treatment systems.
• Systems requiring corrosion-resistant valve materials.
• Gas and liquid piping systems.
• Piping systems requiring quick manual valve operation.

Final valve selection should be based on the actual fluid, pressure, temperature, materials, and connection requirements of the system.

2. Construction of AUTOMA Stainless Steel 3-Piece Ball Valve

2.1. 3-Piece Body Construction

A distinctive feature of the AUTOMA AT300/AT301 is its 3-Piece Body construction, also referred to as a 3-piece body design.

The construction consists of a central body containing the ball and two end connection sections. These components are assembled using a system of bolts and nuts.

Compared with a one-piece body design, the 3-piece construction facilitates disassembly and inspection of the internal valve components.

The valve body is manufactured using the Investment Casting process, providing a construction suitable for the dimensional requirements of an industrial ball valve body.

2.2. Full Bore Ball

The ball is the component directly responsible for controlling fluid flow.

AUTOMA AT300/AT301 uses a Full Bore Ball Valve design, in which the through-hole of the ball is configured as a Full Bore passage.

When the valve is fully open, the fluid flows through a relatively straight flow path, making the design suitable for systems where obstruction to flow caused by the valve structure needs to be minimized.

2.3. Blow-out-proof Stem

The stem transfers rotational movement from the handle to the ball.

AUTOMA uses a Blow-out-proof Stem design, in which the stem is retained within the valve structure rather than relying solely on external installation components.

This is an important design feature for ball valves, particularly when the valve operates under internal pressure.

2.4. R-PTFE Valve Seat

The valve seat is the component in contact with the ball and plays an important role in sealing when the valve is closed.

AUTOMA AT300/AT301 uses Reinforced Teflon (R-PTFE) as the seat material.

R-PTFE provides good chemical resistance and a suitable sealing surface for the Ball Valve construction.

When selecting the valve for a specific chemical service, compatibility between R-PTFE, body/ball/stem materials, and the actual fluid should be checked.

2.5. Locking Handle

AUTOMA AT300/AT301 is equipped with a Locking Handle.

The handle allows the operator to open or close the valve by rotating it 90°. The locking mechanism helps prevent unintended changes in handle position during operation.

2.6. Connection and Sealing Components

In addition to the main components, the valve consists of various parts including:

• Body.
• Cap.
• Ball.
• Seat.
• Stem.
• Gasket.
• Thrust Washer.
• Packing.
• Gland.
• Spring Washer.
• Stem Nut.
• Locking Device.
• Handle.
• Handle Sleeve.

These components work together to form a complete valve assembly, providing the required operating and sealing functions of the Ball Valve.

3. Operating Principle of AUTOMA Ball Valve

3.1. Quarter-Turn Opening and Closing

The AUTOMA ball valve operates based on the rotational movement of the ball.

When the handle is rotated approximately 90°:

Handle → Stem → Ball → Change in flow condition.

When the ball opening is aligned with the pipeline, the valve is in the open position.

When the ball opening is rotated perpendicular to the pipeline, the valve is in the closed position.

With its quarter-turn operating principle, the ball valve can be opened and closed quickly through manual operation.

3.2. Full Bore Flow Path

The Full Bore design provides a relatively unobstructed internal flow path when the valve is fully open.

This is an important feature for systems requiring a large flow passage through the valve and minimizing the influence of the valve structure on fluid flow.

3.3. Fluid Flow Control

AT300/AT301 is primarily designed for on/off service.

During operation, the valve should generally be placed in the fully open or fully closed position according to the intended application. A Ball Valve should not automatically be considered a continuous throttling valve unless the system design specifically requires such operation.

3.4. Role of the R-PTFE Valve Seat

When the valve is closed, the ball contacts the seat to form a sealing interface between the ball and the valve body.

R-PTFE is used at the seat position to provide a sealing surface with suitable chemical resistance for various applications.

However, the temperature and chemical properties of the fluid should still be checked before selecting the material.

4. Materials of AUTOMA AT300 and AT301

4.1. A351 Gr.CF8 / A351 Gr.CF8M Valve Body

The AT300 and AT301 models use two different body material configurations.

Model	Material Body
AT300	A351 Gr.CF8
AT301	A351 Gr.CF8M

A351 Gr.CF8 and A351 Gr.CF8M are cast stainless steel materials used for valve bodies.

The selection between the two models should be based on the material requirements and operating conditions of the system.

4.2. SS304 / SS316 Ball

The ball materials are configured as follows:

Model	Ball
AT300	SS304
AT301	SS316

SS304 is suitable for many general industrial applications, while SS316 is commonly considered when the system requires a higher level of corrosion resistance.

However, actual material compatibility depends on the fluid composition, concentration, temperature, and operating conditions.

4.3. A276 304 / A276 316 Stem

The stem materials of the two models are also configured accordingly:

• AT300: A276 304.
• AT301: A276 316.

The stem is responsible for transmitting movement from the handle to the ball. Therefore, stem material is an important factor to consider when selecting a valve for a specific operating environment.

4.4. R-PTFE Gaskets and Packing

The sealing components include:

• Seat: R-PTFE.
• Gasket: R-PTFE.
• Thrust Washer: R-PTFE.
• Packing: R-PTFE.

The use of R-PTFE for these sealing components provides a material configuration suitable for various industrial applications, particularly systems requiring chemical resistance.

4.5. Difference Between AT300 and AT301

The main material differences can be summarized as follows:

Component	AT300	AT301
Body	A351 Gr.CF8	A351 Gr.CF8M
Ball	SS304	SS316
Stem	A276 304	A276 316
Seat	R-PTFE	R-PTFE
Gasket	R-PTFE	R-PTFE
Packing	R-PTFE	R-PTFE

Therefore, when selecting between AT300 and AT301, the important consideration is not only the valve size but also material compatibility with the operating environment.

5. AUTOMA Stainless Steel Ball Valve Technical Specifications

5.1. Size Range DN8–DN100

AUTOMA AT300/AT301 is available in sizes from 1/4″ to 4″, corresponding to DN8–DN100.

Size	DN	d (mm)	L (mm)	H (mm)	W (mm)
1/4″	8	11	65	48.5	95
3/8″	10	12	65	48.5	95
1/2″	15	15	75	54	105
3/4″	20	19.5	80	65.5	120
1″	25	25	90	72	140
1-1/4″	32	32	110	81	150
1-1/2″	40	38	120	96	170
2″	50	49	140	105	185
2-1/2″	65	64	160	120	220
3″	80	78	180	134.5	270
4″	100	99	215	167	330

These dimensions allow engineers to check installation space and select the appropriate model according to the pipeline diameter.

5.2. Working Pressure

AUTOMA AT300/AT301 has a Working Pressure up to 1000 PSI W.O.G.

In addition to the working pressure specification, the product has the following Pressure Test values:

Pressure Test	Pressure
Shell – Hydraulic Test	10.4 MPa
Seat – Hydraulic Test	7.6 MPa
Seat – Air Test	0.6 MPa

Pressure Test values and Working Pressure should be clearly distinguished during system design. Actual operating conditions must remain within the applicable limits of the valve and piping system.

5.3. Working Temperature

The maximum working temperature specified for the product is up to 180°C.

The product also provides a Pressure-Temperature Chart, showing the variation of allowable pressure according to temperature and valve size.

Therefore, when the system operates at elevated temperatures, the valve should not be selected based solely on a single nominal pressure value. The corresponding Pressure–Temperature conditions should also be considered.

5.4. Thread Connection Standards

AUTOMA AT300/AT301 uses pipe connections according to:

ISO 228 BSPP (G)

The product also provides the following connection options:

• NPT
• BSPT
• Butt-weld

When ordering or replacing the valve, the exact connection standard should be identified to avoid thread mismatch or incompatibility with the existing piping.

5.5. Pressure Test

Pressure Test is one of the important parameters used to evaluate the pressure resistance of the valve.

AUTOMA AT300/AT301 has the following test values:

• Shell Hydraulic Test: 10.4 MPa
• Seat Hydraulic Test: 7.6 MPa
• Seat Air Test: 0.6 MPa

Testing the shell and seat under different conditions allows the pressure resistance of the valve body and the sealing performance of the seat to be evaluated separately.

5.6. Dimensions and Installation

When selecting the valve, in addition to DN/Size, the following factors should also be checked:

• Valve length L.
• Valve height H.
• Handle length W.
• Handle operating clearance.
• Connection type.
• Installation orientation.
• Space required for valve removal and maintenance.

For a 3-piece valve, sufficient space should be provided to remove the connecting components during maintenance.

6. Pressure and Temperature Resistance

6.1. Working Pressure up to 1000 PSI

The working pressure capability of up to 1000 PSI W.O.G. allows AUTOMA AT300/AT301 to be considered for systems requiring relatively high pressure operation.

However, the working pressure must be evaluated together with temperature, valve size, and fluid type.

6.2. Working Temperature up to 180°C

The valve is designed for a working temperature of up to 180°C.

At elevated temperatures, particular attention should be paid to:

• Actual operating pressure.
• Seat material.
• Gasket material.
• Fluid properties.
• Pressure-Temperature Rating.

The 180°C value should not be treated as an independent operating limit without considering the other operating conditions.

6.3. Pressure–Temperature Rating

The AUTOMA Pressure-Temperature Chart indicates the allowable pressure according to temperature for different valve size groups.

This allows engineers to evaluate the valve according to actual operating conditions rather than selecting it solely based on a single pressure value.

6.4. Size Selection According to Operating Conditions

Valve size should be selected based on:

Pipeline size + flow rate + fluid type + pressure + temperature + connection type.

Selecting a valve with the correct DN for the pipeline alone is not sufficient if the pressure, temperature, or material requirements are not compatible.

7. Key Advantages of AUTOMA AT300/AT301 Ball Valve

7.1. Full Bore Design

Full Bore is one of the key features of AUTOMA AT300/AT301.

When fully open, the ball through-hole creates a straight flow path, making the valve suitable for systems requiring a large flow passage through the valve.

7.2. 3-Piece Body Construction

The 3-piece body design facilitates disassembly and inspection of the valve assembly.

This configuration is suitable for systems requiring periodic valve maintenance.

When inspection or replacement of components such as the Ball, Seat, Gasket, or Packing is required, the 3-piece construction provides convenient access to the internal components compared with certain one-piece body designs.

7.3. Blow-out-proof Stem

The Blow-out-proof Stem is an important design feature of AUTOMA AT300/AT301.

This construction helps reduce the risk of the stem being forced out by internal valve pressure, contributing to the overall safety of the valve construction.

7.4. R-PTFE Valve Seat

R-PTFE is used as the seat and for several sealing components.

This material provides good chemical resistance and is suitable for various industrial environments when correctly selected according to the fluid properties.

7.5. Locking Handle

The Locking Handle allows the operator to control the valve position and helps prevent unintended changes to the handle position.

For systems requiring the valve to remain in a fixed open or closed position, this is a useful feature.

7.6. Stainless Steel Materials for Industrial Environments

AT300 uses a CF8/SS304 material configuration, while AT301 uses CF8M/SS316.

These two material configurations allow engineers to select the appropriate valve according to the operating environment and corrosion-resistance requirements of the system.

8. Applications of AUTOMA Stainless Steel 3-Piece Ball Valve

8.1. Water and Water Treatment Systems

AUTOMA AT300/AT301 can be considered for industrial water systems and water treatment piping when the valve materials are compatible with the operating conditions.

The Full Bore design makes the valve suitable for systems requiring a relatively unobstructed flow path when fully open.

8.2. Chemical Piping Systems

R-PTFE provides good chemical resistance, allowing this valve configuration to be considered for systems handling certain chemicals.

However, the valve should not be selected based solely on the presence of PTFE. The following factors should be checked together:

• Chemical concentration.
• Temperature.
• Pressure.
• Body material.
• Ball.
• Stem.
• Seat.
• Gasket.

8.3. Industrial Piping

With a size range of 1/4″–4″, AUTOMA AT300/AT301 can be used for various industrial piping systems within the corresponding size range.

The valve can be used for equipment isolation, pipeline shut-off, or separation of different sections within a system.

8.4. Gas and Liquid Systems

The W.O.G. specification allows the product to be considered for Water, Oil, and Gas applications within the applicable operating conditions.

The actual fluid must still be evaluated for material compatibility before valve selection.

8.5. Systems Requiring Quick Shut-off

With its quarter-turn handle operation, the AUTOMA Ball Valve is suitable for systems requiring quick opening and closing.

Unlike some linear valves requiring multiple turns, a Ball Valve can change its operating position through approximately 90° of handle rotation.

9. Selection Guide for AUTOMA AT300 and AT301

9.1. Determine the Pipeline Size

The first step is to determine the size of the existing or newly designed pipeline.

AUTOMA AT300/AT301 is available in sizes from 1/4″ to 4″, corresponding to DN8–DN100.

Selecting the correct size helps ensure proper connection and compatibility with the piping design.

9.2. Select AT300 or AT301

The selection can be guided by the material configuration:

AT300:

• Body: A351 Gr.CF8.
• Ball: SS304.
• Stem: A276 304.

AT301:

• Body: A351 Gr.CF8M.
• Ball: SS316.
• Stem: A276 316.

AT301 can be considered when the system requires an SS316/CF8M material configuration.

9.3. Check Pressure and Temperature

The following parameters should be determined:

• Working pressure.
• Working temperature.
• Maximum possible pressure.
• System start-up and shutdown conditions.

These conditions should then be compared with the valve’s Pressure-Temperature Rating.

9.4. Check Material Compatibility

This is particularly important when the valve is used for chemical applications.

Compatibility between the fluid and the following materials should be checked:

• CF8/CF8M.
• SS304/SS316.
• R-PTFE.
• Gasket and packing materials.

Material selection should not be based solely on the chemical name without considering its concentration and operating temperature.

9.5. Check the Connection Type

Before ordering, the piping connection should be identified:

• BSPP.
• BSPT.
• NPT.
• Butt-weld.

A mismatch in connection standards may prevent the valve from being directly connected to the existing pipeline or fittings.

10. Installation and Maintenance of AUTOMA Ball Valve

10.1. Pre-installation Inspection

Before installing AUTOMA AT300/AT301, the following should be checked:

• Model.
• Size.
• Material.
• Connection type.
• Flow direction.
• Design pressure.
• Working temperature.
• Valve body condition.
• Seat and sealing component condition.

The pipeline should also be cleaned to minimize the possibility of dust, debris, or foreign particles entering the valve.

10.2. Notes for Threaded Valve Installation

For threaded versions, the correct thread standard for the piping system must be used.

When tightening the valve, the applied force should be distributed appropriately to avoid damaging the valve body or connection.

The handle should not be used as a leverage point for tightening the valve onto the pipeline.

10.3. Leakage Inspection

After installation, leakage should be checked at:

• Connection points.
• Valve body.
• Stem area.
• Seat area during operation.
• Gasket locations.

Leakage testing can be performed under an appropriate pressure condition before the system is officially commissioned.

10.4. Handle and Stem Inspection

During operation, the handle movement and stem operation should be checked.

If the handle becomes excessively difficult to operate or abnormal behavior occurs, excessive force should not be applied. The cause should be investigated first.

10.5. 3-Piece Valve Maintenance

One of the advantages of the 3-piece body configuration is that the valve assembly can be disassembled for inspection of the internal components.

During maintenance, the following components should be inspected:

• Ball.
• Seat.
• Stem.
• Gasket.
• Packing.
• Bolts and nuts.
• Handle locking mechanism.

If the seat or sealing components are found to be damaged, they should be replaced with components compatible with the correct model and material configuration.

11. Conclusion

The AUTOMA AT300/AT301 Stainless Steel 3-Piece Ball Valve is a Stainless Steel 3-Piece Ball Valve designed for industrial piping systems requiring manual fluid shut-off and isolation.

The product features a Full Bore design, 3-piece Investment Casting body, Blow-out-proof Stem, R-PTFE valve seat, and a locking handle. The valve is available in sizes from 1/4″ to 4″, with a working pressure of up to 1000 PSI W.O.G. and a working temperature of up to 180°C.

The two models, AT300 and AT301, provide two main material configurations:

• AUTOMA AT300: Body A351 Gr.CF8, Ball SS304, Stem A276 304.
• AUTOMA AT301: Body A351 Gr.CF8M, Ball SS316, Stem A276 316.

The selection between the two models should be based on pipeline size, pressure, temperature, fluid type, material compatibility, and connection standard.

With its 3-piece body, Full Bore design, and multiple size options, AUTOMA AT300/AT301 is a suitable option to consider for water, liquid, gas, and industrial piping applications requiring a robust stainless steel ball valve with quick opening and closing operation.