The Yoshitake OB-1G is a direct-acting temperature regulator designed specifically for heating applications. It features an external pressure type bellows that ensures distinguished temperature resistance, making it highly suitable for environments where the ambient temperature exceeds the set temperature. The regulator is constructed with a durable cast bronze body and utilizes a double valve structure to provide a larger flow rate compared to single valve types.

Equipped with a union type connection screw, the OB-1G allows for easy plumbing and installation. It also includes an attached adjusting handle, eliminating the need for special tools and making temperature adjustments straightforward. The spindle gland packing utilizes special materials to ensure excellent accuracy during the opening and closing operations of the valve.

Features

1. Easy plumbing due to union type connection screw.
2. No need for adjusting tool due to the attached adjusting handle, making adjustment easy.
3. Double valve structure offers larger flow rate than single valve type.
4. Excellent accuracy since special packing is used for spindle gland packing which affects opening/closing operation of the valve.
5. The OB-1G ensures distinguished temperature resistance due to external pressure type bellows.

Specifications

Specification	OB-1	OB-1G
Application	Heating	Heating
Heating Fluid	Steam, Hot water	Steam, Hot water
Heated Fluid	Cold and hot water, Oil, Non-dangerous fluids	Cold and hot water, Oil, Non-dangerous fluids
Maximum Pressure (Body)	0.7 MPa	0.7 MPa
Maximum Pressure (Thermal bulb)	1.0 MPa	1.0 MPa
Max. Temperature	180°C	180°C
Temperature Adjusting Range (Liquid)	40-120°C	15-100°C
Temperature Adjusting Range (Air)	40-120°C	15-100°C
Ambient Temperature	Set temperature -10°C or less	Set temperature +30°C or less
Body Material	Cast bronze	Cast bronze
Valve Material	Bronze	Bronze
Valve Spindle Material	Stainless steel	Stainless steel
Bellows Material	Phosphor bronze	Phosphor bronze
Thermal Bulb Material	Stainless steel	Stainless steel
Standard Capillary Length	2 m	2 m
Connection	JIS Rc screwed (union joint)	JIS Rc screwed (union joint)

Notes

• If the ambient temperature is higher than the set temperature or less than 40°C, use the OB-1G (with external pressure type bellows).
• Available with capillary of up to 5 meters.
• Available with temperature adjusting range of 30°C (For OB-1 only).
• Available with thermal well (SUS304 made or with a PTFE cap) for liquid.

Temperature Adjusting Range

OB-1

Temperature adjusting range (°C) For liquid	Temperature adjusting range (°C) For air	Withstand temperature (°C)
40-60	40-60	70
50-70	50-70	80
60-80	60-80	90
80-100	80-100	110
100-120	100-120	130

OB-1G

Temperature adjusting range (°C) For liquid	Temperature adjusting range (°C) For air	Withstand temperature (°C)
15-35	15-35	50
20-40	20-40	50
35-55	35-55	70
40-60	40-60	90
50-70	50-70	100
60-80	60-80	110
70-90	70-90	120
80-100	80-100	130

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

Dimensions and Weights

Note: OB-1G has a little difference in bellows structure.

Nominal size	d	L (mm)	H1 (mm)	H (mm)	Weight (kg)
15A	Rc 1/2	148	55	510	11.0
20A	Rc 3/4	148	55	510	11.0
25A	Rc 1	160	60	520	12.0
32A	Rc 1-1/4	195	60	520	12.0
40A	Rc 1-1/2	210	65	530	13.0

Nominal Size Selection Chart (For Steam)

How to use the chart

When selecting the nominal size of a temperature regulator whose inlet pressure (P1), outlet pressure (P2), and steam flow rate are 0.3 MPa, 0.25 MPa, and 60 kg/h, respectively, first find intersection point (a) of the inlet pressure of 0.3 MPa and the outlet pressure of 0.25 MPa. Trace down vertically from this intersection point (a) to find intersection point (b) with the flow rate of 60 kg/h. Since this intersection point (b) lies between nominal sizes 15A or 20A and 25A, select the larger one, 25A.

Parts and Materials

No.	Name of Parts	Material	Q.TY
1	Body	Bronze	1
2	Bottom Cover	Brass	1
3	Union Nipple	Bronze	2
4	Union Nut	Ductile Cast Iron	2
5	Valve	Phosphor Bronze or Bronze	1
6	Spindle Joint	Brass	1
9	Top Cover	Brass	1
10	Gland Packing	PTFE	3
11	Spring	Stainless Steel	1
12	Nut	Steel	1
13	Cap Nut & Washer of Packing & Adapter	Brass	1
14	Spindle	Stainless Steel	1
15	Frame	Cast Iron	1
16	Lock Nut & Washer	Brass & Steel	1
17	Handle	Cast Iron	1
18	Division Plate	Brass	1
19	Bearing Cover	Carbon Steel	1
20	Bearing	Bearing Steel	1
21	Adjusting Screw	Bronze	1
22	Spring	Alloy Steel or ITW	1
23	Spindle	Brass	1
24	Bellows	Phosphor Bronze	1
25	Washer of Bellows	Copper	1
26	Spring Plate	Cast Iron	1
27	Bellows Cover	Cast Iron	1
28	Bellows Washer	Brass	1
29	Bellows Nut	Steel	1
30	Guard Metal Fitting	POM	2
31	Flexible Tube	Copper Tube	1
32	Flexible	Stainless Steel	1
33	Thermal Element Pipe	Stainless Steel	1
34	Screw Flange	Cast Stainless Steel	1
35	Thermal Element Flange	Cast Stainless Steel	1
36	Cap	Stainless Steel	1
37	Bolt	Steel	1set
38	Gasket	Non-Asbestos	1
39	Fin	Stainless Steel	1set