JSB, Air Operated, Angle Seat Valve

SMC  |  Fluid Process Valves

SMC JSB Series Angle Seat Valves

The SMC JSB Series is an air operated angle seat valve for controlling steam, water, and air. Its angled seat design keeps the flow path straight and open, delivering high flow capacity with low pressure drop, while a stainless steel 316L equivalent body and long cycle life make it a durable choice for demanding process lines. Available in seven port sizes from 3/8 inch to 2 inch, in NPT, Rc, and G thread connections. Automation Distribution is an authorized SMC distributor.

Media

Steam, Water, Air

Port Sizes

3/8 in to 2 in

Cycle Life

Up to 10 million

Body Material

SS 316L equiv.

Actuation

Air Operated (N.C.)

What Is an Angle Seat Valve?

An angle seat valve is a pneumatically actuated on/off valve in which the seat sits at an angle (typically 45 degrees) to the flow path. When the valve opens, the piston lifts the plug clear of the flow line rather than into it, so the media passes through with far less turbulence and restriction than a conventional globe valve. The result is a higher flow coefficient (Cv) and lower pressure loss for the same body size - which is why angle seat valves are the default choice for steam, hot water, and high-cycle dosing and filling lines.

The JSB Series is SMC's high-flow, long-life angle seat platform. Its optimized flow channel achieves roughly 2.5 times the flow of a comparable globe-style valve, and its squeeze seal with scraper function is rated for up to 10 million cycles on air and water, or 3 million cycles on steam. A built-in visual position indicator shows open/closed status at a glance, and the valve's individual serviceable parts keep long-term maintenance simple.

Where JSB Valves Are Used

The combination of high flow, tight shutoff, and long service life makes the JSB Series well suited to process industries where valves cycle frequently and downtime is costly:

Food & Beverage Chemical Processing Water Treatment Pharmaceutical Steam & CIP Systems General Manufacturing

Typical duties include steam supply and control, hot and cold water dosing, tank fill and drain, and air line sequencing where fast, repeatable actuation with minimal pressure loss is required.

JSB or VXB - Which Angle Seat Valve?

Automation Distribution stocks two air operated angle seat valve families from SMC. The right one depends on your flow, size range, and cycle demands.

Choose JSB when

You need maximum flow and the longest service life, larger port sizes up to 2 inch, or high-cycle steam and water duty. The JSB is the high-flow, long-life platform.

Consider VXB when

You are working in smaller port sizes (3/8 inch to 3/4 inch), a compact height matters, or you want a rubber-seal steam valve with low leakage. View VXB angle seat valves »

Select Your JSB Valve by Size & Thread

All JSB valves below are air operated, normally closed (N.C.), threaded-body construction with a stainless steel 316L equivalent body. Pick your port size, then choose the thread standard your line uses - NPT (North American tapered), Rc (tapered BSPT), or G (parallel BSPP).

1-1/4 inch  | DN32  | JSB51  | $700
1-1/2 inch  | DN40  | JSB61  | $820

How to Read a JSB Part Number

JSB 41 - ST 25 AN - 4S

JSB - Air operated angle seat valve series

41 - Valve size code (11 through 71 across the seven port sizes)

ST - Threaded (screwed) body connection

25 - Nominal port size in mm (10, 15, 20, 25, 32, 40, 50)

A - Air operated actuator

N / R / F - Thread standard: N = NPT, R = Rc, F = G

4S - Body/actuator size designation

Frequently Asked Questions

What is the SMC JSB Series used for?

The JSB Series is an air operated angle seat valve used to control steam, water, and air in process applications such as food and beverage, chemical processing, water treatment, pharmaceuticals, and general manufacturing. It is chosen where high flow, low pressure drop, and long cycle life matter.

How does an angle seat valve differ from a globe valve?

In an angle seat valve the seat is angled to the flow path, so the plug lifts out of the flow line when open. This produces a straighter, less restricted path and a higher flow coefficient than a globe valve of the same size, which lowers pressure loss and energy use across the system.

What sizes and thread types are available?

JSB valves are offered in seven port sizes from 3/8 inch (DN10) to 2 inch (DN50), each available in NPT, Rc (BSPT), or G (BSPP) threaded connections.

Can the JSB be used with steam?

Yes. The JSB Series is rated for steam, water, and air, with a stainless steel 316L equivalent body and a service life of up to 3 million cycles on steam and 10 million cycles on air or water.

Are normally open or double-acting versions available?

The valves listed here are the air operated, normally closed (N.C.) threaded-body configuration. SMC also builds the JSB Series in normally open and double-acting versions, and in clamp and butt-weld body styles. Contact Automation Distribution for those configurations.

Need Help Sizing a JSB Valve?

Automation Distribution is an authorized SMC distributor. Send us your media, line pressure, flow requirement, and connection standard, and our team will help you spec the right JSB angle seat valve - or a normally open, double-acting, clamp, or butt-weld configuration built to order.

Compare the VXB Series ยป