TLV BD800 is a bypass blow valve with a scale removal function and inline maintainability for long service life. It is designed for use in high temperature and high pressure applications, making it ideal for installation on steam trap bypass lines. The proven special material combined with a unique cleaning mechanism reduces the burden of valve maintenance and operation.

Features

• Easy-to-use scale removal function ensures reliable long-term sealing performance to avoid internal leakage.
• Gland packing proven in high pressure applications prevents external leakage.
• Highly durable materials to prevent erosion.
• Replaceable gland packing, valve stem, valve seat and gaskets for long product service life.
• No valve handle to eliminate the risk of erroneous operation.
• Spanner cap protects valve stem from weather and foreign matter, and can be used to operate the valve or tighten the gland retainer.

Specifications

Model	BD800
Connection	Screwed, Socket Welded, Flanged
Size (mm)	15, 20, 25
Maximum Operating Pressure (PMO)	6.5 MPaG
Maximum Operating Temperature (TMO)	425 °C
Applicable Standards	API 598, ASME B16.34
Seat Leakage (Gas test in accordance with API 598)	0 bubbles / 15 seconds @ 0.6 MPaG
Applicable Fluids	Steam, Water, Air

WARNING

Do not use for toxic, flammable or otherwise hazardous fluids. PRESSURE SHELL DESIGN CONDITIONS (NOT OPERATING CONDITIONS): Maximum Allowable Pressure (MPaG) PMA: 6.5; Maximum Allowable Temperature (°C) TMA: 425. To avoid abnormal operation, accidents or serious injury, DO NOT use this product outside of the specification range. Local regulations may restrict the use of this product to below the conditions quoted.

Material Specifications

No.	Description	Material	JIS	ASTM/AISI
1	Body	Stainless Steel	—	A182 Gr.F304
2	Bonnet	Carbon Steel	—	A105
3	Valve Seat	—	—	—
4	Valve Seat Gasket	Stainless Steel	SUS316L	AISI316L
5	Bonnet Gasket	Graphite/Stainless Steel	- / SUS304	- / AISI304
6	Valve Stem	—	—	—
7	Gland Packing	Graphite	—	—
8	Gland Retainer	Stainless Steel	SUS303	AISI303
9	Spanner Cap	Cast Stainless Steel	—	A351 Gr.CF8
10	Bonnet Bolt	Stainless Steel	—	A193 Gr.B8 Cl.2
11	Bonnet Nut	Stainless Steel	—	A194 Gr.8
12	Flange	Cast Stainless Steel	—	A351 Gr.CF8
13	Nameplate	Stainless Steel	SUS304	AISI304
14	Gland Packing Removal Tool	Stainless Steel	—	—

Configuration

Dimensions

BD800 Screwed

Size (mm)	L	H	H1	Ø D	Weight (kg)
15	80	140	115	40	2.2
20	92	140	115	40	2.5
25	160	140	115	50	3.0

Rc(PT), other standards available

BD800 Socket Welded

Size (mm)	L	H	H1	Ø D	Ø C	h	Weight (kg)
15	80	140	115	32	22.2	11	2.2
20	92	140	115	38	27.7	13	2.5
25	160	140	115	48	34.5	14	3.0

BD800 Flanged

Size (mm)	L (ASME 150RF)	L (ASME 300RF)	L (ASME 600RF)	H	H1	Weight (kg)*
15	152	152	165	140	115	4.1
20	178	178	190	140	115	5.4
25	203	203	216	140	115	6.5

Other standards available, but length and weight may vary. Weight is for Class 600RF.

Cv Values

Nominal Valve Size (mm)	15	20	25
Cv (US)	3.5	3.5	3.5
Cv (UK)	2.9	2.9	2.9
Kvs (DIN)	3.0	3.0	3.0

Installation

WARNING

Take measures to prevent people from coming into direct contact with product outlets. Failure to do so may result in burns or other injury from the discharge of fluids.

INFO

Before using the product, ensure piping is cleaned and flushed to remove foreign matter. Failure to observe this precaution may cause leakage from the valve seat. Do not use excessive force when connecting threaded pipes to the product. Over-tightening may cause breakage leading to fluid discharge.

1. When the product is shipped from the factory, the valve stem is positioned in the lowest, valve-closed position.
2. Before installation, be sure to remove all protective seals.
3. Before installing the product, open the inlet valve and blow out the piping to remove any piping scraps, dirt and oil. Close the inlet valve after blowdown.
4. Install the product so the arrow on the body is pointing in the direction of flow.
5. Install outlet piping.

Operation

Adjusting the Valve Aperture

1. Remove the spanner cap by turning it counter-clockwise.
2. Place the spanner cap as shown in Figure A, adjust the valve aperture by turning the valve stem. The adjustment can also be made by using the narrow open end of the spanner cap as shown in Figure B.

3. Once the adjustment is made, replace the spanner cap. This prevents unintentional change of the valve aperture and protects the valve stem against rainwater or foreign matter.

Preventing Erroneous Operation of the Valve Stem

A hole in the spanner cap allows it to be fixed by passing a wire and tightening it around the piping or flange. Restricting movement of the spanner cap prevents the valve from being operated erroneously.

Relation between CV / Kvs Values and No. of Turns of the Valve Stem

Maintenance

WARNING

When using the spanner cap, be sure to use heat-resistant gloves. Disassembling or removing the product when it is hot or under pressure may lead to discharge of fluids, causing burns, other injuries or damage.

Retightening of the Gland Section

When fluid leaks from the gland section, retighten the gland holder. Make sure that the valve is in the fully closed position.

1. Remove the spanner cap by turning it counter-clockwise.
2. Tighten the gland holder. The gland holder can be tightened with the spanner cap as well as a spanner wrench (distance across flats: 22 mm).
3. After retightening is complete, replace the spanner cap.

Cleaning the Valve Seat Section

When scale adheres to the valve seat section, sealing is inhibited, causing fluid leakage. Restore sealing performance by following these steps:

1. Remove the spanner cap.
2. Turn the valve stem counter-clockwise one to two times.
3. Turn the valve stem clockwise (right rotation) until it cannot be turned any further.
4. Repeat steps 2 and 3 two to three times. Check whether fluid is leaking on the secondary side.
5. When no fluid is leaking and the valve closes fully, cleaning is complete. If leakage still occurs, repeat steps 2 and 3 another two to three times.

Disassembly/Reassembly and Tightening Torques

Part Name	Torque (N·m)	Distance Across Flats (mm)
Bonnet Nut	80	17
Gland Holder	60	22
Valve Seat	80	21

(Coat all threaded portions with anti-seize.)

Troubleshooting

Problem	Cause	Remedy
Fluid is leaking from the outlet (even) when the valve is closed	The valve stem is not tightened sufficiently	Place the spanner on the flat surfaces of the valve stem and tighten to the proper torque (16 N·m). Tighten the spanner cap to the proper torque (16 N·m).
	The sealing surfaces of the valve seat and valve stem are damaged or clogged with rust and scale	Clean the valve seat and valve stem; if leakage does not stop, replace with a new valve seat and/or valve stem
Fluid is leaking from the gland section	The gland holder is loosened	Retighten the gland holder, clean or replace with new parts
The valve stem does not move	The valve stem is clogged with rust and scale	Clean or replace with a new valve stem
Fluid is leaking from a place other than the outlet	Fluid is leaking from between the bonnet and body; Gasket deterioration or damage; Sealing surfaces are damaged or clogged	Replace with new gasket(s)
	Improper tightening torques were used	Tighten to the proper torque
The valve stem and the valve seat frequently become damaged	Water hammer has occurred	Check if the valve stem is over-tightened; replace if deteriorated. Check and correct the piping