TLV COS-21 steam pressure reducing valves are innovative devices designed to supply dry saturated steam at a constant pressure. Steam-using equipment can perform its intended operation only when dry saturated steam is available. Steam containing entrained condensate, scale, or air not only reduces steam equipment productivity but also shortens the life of pressure reducing valves. The COS/COSR series helps eliminate these problems by providing reliable pressure control.

Configuration

The main components include the main body, trap body, trap cover, separator, and float. Maintenance and repair kits are available for the various functional sections.

Specifications

Refer to the product nameplate for detailed specifications.

Model	COS-3 / COSR-3	COS-16 / COSR-16 / COSR-16HT	COS-21 / COSR-21
Primary Pressure Range	0.1 to 0.3 MPaG	0.2 to 1.6 MPaG	1.35 to 2.1 MPaG
Secondary Pressure Adjustable Range	0.01 to 0.05 MPaG	Within 10 to 84% of primary pressure	Within 10 to 84% of primary pressure
Minimum adjustable pressure	0.03 MPaG	0.55 MPaG	0.55 MPaG
Pressure differential	0.07 to 0.85 MPaG	Maximum 0.85 MPa	Maximum 0.85 MPa
Minimum Adjustable Flow Rate	5% of rated flow rate	5% of rated flow rate (10% for ≥ 65 mm)	5% of rated flow rate (10% for ≥ 65 mm)

WARNING

To avoid malfunctions, product damage, accidents or serious injury, install properly and DO NOT use this product outside the specification range.

Piping and Installation

• Install for use under conditions in which no freeze-up will occur.
• Install for use under conditions in which no water hammer will occur.

Recommended Straight Pipe Runs

To ensure stable steam flow, it is recommended that the COS/COSR be installed on straight runs of piping.

Inlet (primary side) of the COS/COSR

• Maintain a straight piping run of 10d or more when a manual valve, a strainer or an elbow, etc. is installed.
• Maintain a straight piping run of 30d or more when an automated valve (on-off valve) is installed.

Outlet (secondary side) of the COS/COSR

• Maintain a straight piping run of 15d or more when a manual valve, a strainer or an elbow, etc. is installed.
• Maintain a straight piping run of 30d or more when a safety valve, another pressure reducing valve, or a control valve is installed.

Installing a Control Valve

A control valve installed between the COS/COSR and the steam equipment may raise pressure between them when the control valve is closed. The control valve should be installed close to the steam-using equipment.

Installation Angle

Make sure the COS/COSR is installed on horizontal piping, so that the arrow mark on the body matches the direction of steam flow and the adjustment screw section faces up. Allowable inclination is 10 degrees in the fore-aft direction and 15 degrees in the plane perpendicular to the steam flow line.

Spacer Installation

If spacing adjustment is necessary to accommodate installation, install a spacer on the outlet flange.

Piping Support

Install the COS/COSR, paying attention to avoid excessive load, bending or vibration. Support the inlet and outlet pipes securely.

Maintenance Space

Leave sufficient space for maintenance, inspection and repair.

Trap Outlet Pipe (COS)

For ease of maintenance, installation of a union connection is recommended for the trap outlet pipe. Connect the outlet pipe to a condensate return line, or extend it to a trench.

Blowdown Valve (COS)

In an environment of heavy dirt or scale, or when the steam equipment is used only periodically, be sure to use a blowdown valve.

External Sensing Line

North American models are factory prepared for external sensing. An external sensing line MUST be installed.

Adjustment

1. It is necessary to blow down all pipe lines thoroughly.
2. Make sure that the shutoff valve and the bypass valve located upstream and downstream of the COS/COSR are completely closed.
3. Remove the spanner cap, loosen the locknut and turn the adjustment screw counterclockwise to reduce tension on the coil spring.

4. Slowly, fully open the shutoff valve at the inlet of the COS/COSR.
5. Slightly open the shutoff valve at the outlet of the COS/COSR.
6. Turn the adjustment screw until the desired outlet pressure is obtained. Wait several minutes.

7. Slowly, fully open the shutoff valve on the outlet side.
8. After setup, tighten the locknut and replace the spanner cap.

Disassembly and Inspection

It is a recommended practice to dismantle and inspect the COS/COSR once a year for preventive maintenance purposes.

Before disassembly, remove all steam from the piping. Relieve residual steam pressure by loosening slightly the spring housing bolt and pilot screen holder or sensing line plug.