TLV COS-3, COS-16, and COS-21 (along with the COSR series) are technologically advanced self-actuated steam pressure reducing valves. 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 supplying dry saturated steam at a constant pressure at all times. They combine a pressure reducing valve with a built-in cyclone condensate separator and a free float steam trap to provide accurate control and steam conditioning, maximizing process system performance.

Features

1. Space-saving unit simplifies system layout, piping, and maintenance.
2. Self-aligning shock-absorbing spherical piston and advanced pilot regulator designs maintain secondary steam pressure accuracy, even during adverse process conditions.
3. Built-in cyclone separator, with condensate separation efficiency as high as 98%, and self-modulating free float steam trap provide dry, high-quality steam supply.
4. Major internal components made of stainless steel for long service life.
5. Large surface area integral screens for pilot valve and main valve extend trouble-free service.
6. Internal secondary pressure-sensing channel makes external sensing line unnecessary.
7. COS-16, sizes DN 65 and larger have a silencer for noise reduction.

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 (1 to 3 barg)	0.2 to 1.6 MPaG (2 to 16 barg)	1.35 to 2.1 MPaG (13.5 to 21 barg)
Secondary Pressure Adjustable Range	0.01 to 0.05 MPaG (0.1 to 0.5 barg)	Within 10 to 84% of primary pressure (Min: 0.03 MPaG / 0.3 barg)	Within 10 to 84% of primary pressure (Min: 0.55 MPaG / 5.5 barg)
Pressure Differential	0.07 to 0.85 MPaG (0.7 to 8.5 barg)	Max pressure differential of 0.85 MPa (8.5 bar)	Max pressure differential of 0.85 MPa (8.5 bar)
Minimum Adjustable Flow Rate	5% of rated flow rate	5% of rated flow rate (10% for sizes 65 mm and larger)	5% of rated flow rate (10% for sizes 65 mm and larger)

WARNING

To avoid malfunctions, product damage, accidents or serious injury, install properly and DO NOT use this product outside the specification range. Local regulations may restrict the use of this product to below the conditions quoted.

Configuration

No.	Description	Material
1	Main Body	Cast Iron / Ductile Cast Iron / Cast Stainless Steel
2	Trap Body	Same material as main body
3	Trap Cover	Same material as main body
4	Separator	Stainless Steel
5	Float	Stainless Steel
6	Float Cover	Same material as main body
7	Trap Valve Seat	Stainless Steel
8	Separator Screen	Stainless Steel
9	Main Valve Seat	Stainless Steel
10	Main Valve	Stainless Steel
11	Main Valve Holder	Stainless Steel
12	Piston	Stainless Steel
13	Cylinder	Stainless Steel
14	Pilot Screen	Stainless Steel
16	Pilot Body	Same material as main body
17	Pilot Valve	Stainless Steel
18	Pilot Valve Seat	Stainless Steel
19	Diaphragm	Stainless Steel
22	Coil Spring	Carbon Steel
23	Adjustment Screw	Cr-Mo Steel

Piping and Installation

Recommended Straight Pipe Runs

If the COS/COSR is installed either directly before or after an elbow or control valve, unevenness in flow may result in chattering and unstable pressure. 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 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 is installed.
• Maintain a straight piping run of 30d or more when a safety valve, another pressure reducing valve, a control valve, or an automated valve is installed.

Installing a Control Valve

A control valve (i.e. for temperature control) installed between the COS/COSR and the steam equipment may raise pressure between the COS/COSR and the control valve when the control valve is closed. Therefore, the control valve should be installed close to the steam-using equipment. A safety valve should be installed downstream of the control valve.

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. Make sure the end of the pipe is above the waterline to prevent dirt and water from being sucked up by the vacuum formed during trap closure.

Strainer Installation (COSR)

A strainer should be installed ahead of the COSR. The strainer should be 60 mesh or finer, but not so fine that it causes constriction of the flow area. The strainer should be installed horizontally and at 90° to its normal orientation to the pipeline, in order to prevent condensate accumulation in the screen body.

External Sensing Line

North American models are factory prepared for external sensing. An external sensing line MUST be installed. DO NOT SUPPLY STEAM until all piping and a 10 mm (3/8") secondary pressure sensing line with a slightly falling pitch have been properly installed.

DANGER

Keep the shutoff valve in the pressure sensing line open at all times during operation. If the shutoff valve is closed, COS/COSR will fully open and PRIMARY PRESSURE WILL BE SUPPLIED TO THE EQUIPMENT.

Adjustment

1. 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. Allow sufficient time for condensate remaining at the inlet to be discharged.
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.
9. When shutting down the system, always close the outlet shutoff valve first and then the inlet valve.

Regular Inspection and Maintenance

To ensure long service life, the following inspection and maintenance should be done regularly:

• Separator Screen (COS only), Pilot Screen: Disassemble and clean annually.
• Main Valve, Main Valve Seat, Pilot Valve and Pilot Valve Seat: Replace after 15,000 hours.
• Piston Ring: Replace after 8,000 hours.
• Piston: Replace after 30,000 hours.
• Trap Valve Seat: Replace after 40,000 hours.
• Diaphragm: Replace after 30,000 hours.

Dimensions

Trap Discharge Capacity

WARNING

DO NOT use this product under conditions that exceed maximum differential pressure, as condensate backup will occur!