Yoshitake AL-140 is a closed-type safety relief valve made of cast stainless steel (SCS14A). It is designed to prevent accidents caused by abnormal pressure rise in various pressure vessels, instrumentation devices, and at the outlet of pressure reducing valves. It features a popping structure that ensures reliable discharge and a closed design to prevent fluid leakage. It is suitable for steam, air, cold and hot water, oil, and other non-dangerous fluids.

Features

• Safety valve of all stainless steel made. SCS14A (equivalent to SUS316) with outstanding corrosion resistance is used for the rim parts.
• Popping structure ensures reliable discharge.
• Simple structure and easy to handle.
• Closed structure prevents fluid leakage.

Specifications

Model	AL-140	AL-140H
Structure	Closed type	Closed type
Application	Steam, Air, Cold and hot water, Oil, Other non-dangerous fluids	Steam, Air, Cold and hot water, Oil, Other non-dangerous fluids
Working pressure	0.05-1.0 MPa	1.0-2.0 MPa
Maximum temperature	220°C *	220°C *
Spring case	Cast stainless steel	Cast stainless steel
Valve, valve seat	Cast stainless steel (SCS14A)	Cast stainless steel (SCS14A)
Connection	JIS Rc screwed	JIS Rc screwed

• The maximum temperature is 150°C when using for water, oil, or other liquids.

TIP

• AL-140T is recommended for hot and cold water application when working pressure under 1.0MPa.

Dimensions and Weights

AL-140 Dimensions

Nominal size	d	D (mm)	L (mm)	H1 (mm)	H (mm)	Flow area (mm²)	Weight (kg)
15A	Rc 1/2	16	34	40	128.5	20.1	0.7
20A	Rc 3/4	21	38	42	129	34.6	0.8
25A	Rc 1	26	43	51.5	148	53.0	1.1
32A	Rc 1-1/4	33	50	61.5	182	93.3	2.0
40A	Rc 1-1/2	41	60	64	206	135.2	3.0
50A	Rc 2	51	75	76	246.5	208.2	5.0

AL-140H Dimensions

Nominal size	di x D x do (mm)	L (mm)	H1 (mm)	H (mm)	Flow area (mm²)	Weight (kg)
15A	Rc 1/2 x 16 x Rc3/4	36	42	126.5	20.1	0.9
20A	Rc 3/4 x 21 x Rc 1	38	46	130.5	34.6	1.0
25A	Rc 1 x 26 x Rc 1-1/4	46	55	150.5	53.0	1.5
32A	Rc 1-1/4 x 33 x Rc 1-1/2	54	61.5	195	93.3	2.5
40A	Rc 1-1/2 x 41 x Rc 2	63	67	227.5	135.2	4.6
50A	Rc 2 x 51 x Rc 2-1/2	77	80	303.5	208.2	8.8

• Screwed connection size of the outlet side is 1 size larger than the nominal size.

Structure

No.	Part name	Material
1	Spring case	Cast Stainless Steel (SCS14A or SCS13)
2	Valve seat	Cast Stainless Steel (SCS14A)
3	Valve	Cast Stainless Steel (SCS14A)
4	Spindle	Stainless Steel (SUS303)
5	Spring	Stainless Steel (SUS304)
6	Bottom spring plate	Stainless Steel
7	Top spring plate	Stainless Steel
8	Adjusting screw	Stainless Steel
9	Lock nut	Stainless Steel
10	Cap	Stainless Steel
11	Gasket	PTFE
12	Gasket	PTFE
13	Name plate	Stainless Steel

Blowout Operation

As the inlet pressure approaches the blowout pressure, the force of fluid pushing up the valve approaches the force of the spring pressing down the valve. The safety relief valve commences to blow when the inlet pressure reaches around 3% below the blowout pressure. The fluid accumulates gradually on the pressure groove and when the fluid pressure reaches the blowout pressure the valve pops.

Closing Operation

Since the inlet pressure of the safety relief valve decreases when the fluid is released into the atmosphere by the pop action of valve, the force of fluid lift is lowered. At this point, the repelling force of the spring becomes larger than the force of fluid lift and thus the valve closes. In addition, while the safety relief valve discharges, pressure of fluid entering into the back of the valve (back pressure) adds to the closing force.

Capacity Tables

For Steam (at Saturated Temperature)

Capacity (Pressure vessel structure standard) [kg/h]

Nominal size	0.05 MPa	0.1 MPa	0.2 MPa	0.3 MPa	0.4 MPa	0.5 MPa	0.6 MPa	0.7 MPa	0.8 MPa	0.9 MPa	1.0 MPa
15A	15	20	29	40	50	60	70	80	90	100	109
20A	27	35	51	69	87	104	121	138	155	172	189
25A	42	54	78	105	133	159	186	212	237	263	289
32A	70	91	132	178	224	268	313	356	400	443	487
40A	105	136	198	266	335	402	468	534	599	664	729
50A	163	211	306	411	518	621	723	824	924	1025	1129

For Air (at 20°C)

Capacity (Pressure vessel structure standard) [kg/h]

Nominal size	0.05 MPa	0.1 MPa	0.2 MPa	0.3 MPa	0.4 MPa	0.5 MPa	0.6 MPa	0.7 MPa	0.8 MPa	0.9 MPa	1.0 MPa
15A	25	33	48	65	81	98	114	131	147	164	181
20A	44	57	83	111	140	169	197	226	254	283	311
25A	67	87	127	171	215	258	302	346	390	433	477
32A	113	147	214	288	362	435	509	582	656	730	803
40A	169	221	321	431	542	652	762	872	982	1093	1203
50A	262	341	496	666	836	1006	1176	1346	1516	1687	1857

For Water (Accumulation: 25%)

Capacity (Yoshitake standard) [m³/h]

Nominal size	0.05 MPa	0.1 MPa	0.2 MPa	0.3 MPa	0.4 MPa	0.5 MPa	0.6 MPa	0.7 MPa	0.8 MPa	0.9 MPa	1.0 MPa
15A	0.4	0.5	0.9	1.1	1.3	1.5	1.6	1.8	1.9	2.0	2.1
20A	0.6	0.9	1.6	2.0	2.3	2.6	2.8	3.1	3.3	3.5	3.7
25A	1.0	1.5	2.5	3.1	3.6	4.0	4.4	4.7	5.1	5.4	5.7
32A	1.8	2.6	4.5	5.5	6.3	7.1	7.8	8.4	9.0	9.5	10.0
40A	2.7	3.8	6.5	7.9	9.2	10.3	11.3	12.2	13.0	13.8	14.6
50A	4.1	5.9	10.0	12.3	14.2	15.9	17.4	18.8	20.1	21.3	22.4

INFO

When the set pressure is 1.0 MPa, and the valve size is 50A, the capacity of AL-140 is 22.4 m³/h when the inlet pressure reaches 1.25 MPa (accumulation becomes 25%) after the fluid pressure reaches the set pressure of 1.0 MPa.

Installation

WARNING

1. Do not install any closing device such as a stop valve at inlet or outlet sides of the product.
2. Install an exhaust pipe on outlet side of the product, and lead it to a place where there is no risk of physical damage even if fluid blows out.
3. Do not disassemble the product.
4. When installing, tighten the hexagonal part of the valve seat with a spanner. Do not adjust its direction by rotating the outlet piping.
5. Do not apply viscous fluid that may make fixation of the valve and valve seat.

TIP

• Before installing the product, remove foreign substances and scale from the piping.
• When installing the product, match the direction of fluid flow with the inlet and outlet of the product respectively.
• Install the product vertically with the cap facing upward.
• Securely support and fasten the pipes.
• Connect the product to the pipes securely.
• Inner diameters of pipe mount and of exhaust pipe shall be more than those of each inlet and outlet of the product.

Pipe Mount

1. Pipe mount should have sufficient strength and rigidity against stress which are induced by reaction force in opposite direction of the exhaust through the axis of the exhaust pipe.
2. Install the product vertically as close as possible to the can body and the header to prevent pressure loss in pipe mount.

Exhaust Pipe

1. Install exhaust pipe and drip pan elbow so that the product can not be subject to the stress caused by thermal expansion of equipment and by dilatation of the exhaust pipe due to thermal action of blowout.
2. Inner diameter of exhaust pipe shall be more than that of the product outlet to avoid improper back pressure.

Maintenance

Daily Inspection

Check the following items while the system is in operation:

• Corrosion or crack on the product
• Leakage from the product under normal working pressure
• Leakage from joints between the product and piping

Monthly Inspection

1. Check that there is no loose piping at inlet and outlet side of the product. In addition, check that the cap is fastened securely.
2. Check the operation of the product by raising fluid pressure to the set pressure.