Yoshitake OB-2000 is a pilot operated temperature regulator designed for heating applications using steam. The heated fluid can be cold and hot water, oil, or other non-dangerous fluids. It features a ductile cast iron body with a stainless steel main valve and diaphragm, utilizing a bellows-type thermal bulb for accurate temperature control. This regulator offers exceptional controllability with a large capacity, making it ideally suited for heat exchangers, water heaters, air-conditioning equipment, and chemical processing systems. The OB-2000 can handle maximum body pressures up to 2.0 MPa and withstand temperatures up to 220°C, with a wide temperature adjusting range from -8 to 183°C. It is available in both screwed (JIS Rc) and flanged (JIS 10K FF, 20K RF) connections to accommodate various piping requirements.

OB-2000 Screwed Type

OB-2000 Flanged Type

Features

• Large capacity: Designed to handle significant flow volumes.
• Excellent sealability: Ensured by the spherical valve design.
• Wide adjusting range: The thermal bulb can be installed in any direction.
• Easy maintenance: The body and thermal bulb are easy to attach and detach, allowing for quick replacements to accommodate thermal specification changes.

Specifications

Specification	Value
Model	OB-2000
Application (Heating)	Steam
Application (Heated)	Cold and hot water, Oil, Non-dangerous fluids
Maximum Pressure (Body)	2.0 MPa *1
Maximum Pressure (Thermal bulb)	1.0 MPa
Minimum Differential Pressure	0.05 MPa
Maximum Temperature	220°C
Temperature Adjusting Range	-8 to 183°C
Valve Seat Leakage	0.01% or less of rated flow rate
Material (Body)	Ductile cast iron (FCD450)
Material (Main valve, valve seat)	Stainless steel
Material (Diaphragm)	Stainless steel
Material (Pilot valve, pilot valve seat)	Stainless steel
Material (Thermal bulb)	Copper pipe (nickel chrome plated) *2
Standard Capillary Length	2m
Connection	JIS Rc screwed, JIS 10K FF / 20K RF flanged

Notes

*1 Maximum pressure of JIS 10K FF flanged is 1.0 MPa. *2 In case of attached thermal well (stainless steel), the bush of thermal bulb will be unnecessary.

• Available with thermal well (stainless steel).
• Available with capillary of 3 or 5 meters.
• Available with NPT or BSPT screwed.
• Available with ASME or EN flanged.

Temperature Adjusting Range

Temperature Adjusting Range (°C)	Withstand Temperature (°C)
-8 to 15	35
10 to 36	56
30 to 62	82
55 to 94	114
80 to 127	147
115 to 183	203

::: note The term "withstand temperature" means the temperature from pressure resistance of the bellows. :::

Dimensions and Weights

Screwed Type (JIS Rc)

Nominal Size	d	L	H1	H	A	E	F	G	Weight (kg)
15A	Rc 1/2	150	170	244	200	45	169	222	14.1
20A	Rc 3/4	150	170	244	200	45	169	222	14.1
25A	Rc 1	160	175	251	226	46	174	227	18.1
32A	Rc 1-1/4	180	192	282	226	55	182	235	21.6
40A	Rc 1-1/2	180	192	282	226	55	182	235	21.6

Flanged Type (JIS 20K RF / JIS 10K FF)

Nominal Size	L	H1	H	A	E	F	G	Weight (kg)
15A	146 (142)	170	244	200	45	169	222	15.6 (15.4)
20A	146 (142)	170	244	200	45	169	222	16.1 (15.9)
25A	156 (152)	175	251	226	46	174	227	21.1 (20.7)
32A	176 (172)	192	282	226	55	182	235	24.1 (23.7)
40A	196 (192)	192	282	226	55	182	235	24.6 (24.2)

INFO

Values within parentheses are for JIS 10K FF flanged type.

Nominal Size Selection

When selecting the nominal size of a temperature regulator whose inlet pressure (P1), outlet pressure (P2), and steam flow rate are 0.5 MPa, 0.4 MPa, and 400 kg/h, respectively, first find intersection point (a) of the inlet pressure of 0.5 MPa and the outlet pressure of 0.4 MPa. Trace down vertically from this intersection point (a) to find intersection point (b) with the flow rate of 400 kg/h.