Manufacturer:  Fushiman Co.,LTD.
Model: PRL

Model	Nominal Diameter	Primary Pressure	Secondary Side Setting Range	Maximum Operating Temperature	Body Material	Connection
PRL	65〜150	MAX. 500kPa	1～50kPa	80℃	FC,SCPH,SCS	Flange

• Low-pressure, automatic diaphragm-type pressure relief valve for air.
• For large flow (Nominal diameter 65–150).
• For small flow (Nominal diameter 15–50), please use PLG61-2 type pressure relief valve or PMD31L type pressure relief valve.

Specifications and Materials

Fluid	Nominal Diameter	Pressure kPa		Tempera- ture (°C)	Main Material			Pipe Connec- tion
		Primary Side	Secondary Set Range		Valve Body	Valve Body & Valve Seat	Diaphragm
Air and other non-corrosive gases	65–150	500 or less	1.0–50 (2)	0–80	Cast Iron	Stainless Steel	Synthetic Rubber	Flange JIS 10K Full Face

Note:

1. The size of the top work (adjustment part) may vary. Please refer to the “Secondary Set Pressure Range (Spring section)” and the “Maximum Differential Pressure by Top Work Type” below.
2. This entire range cannot be covered by one screw. Please refer to the “Secondary Set Pressure Range (Spring section)” and “Top Work Type Maximum Differential Pressure” below.

Additional Information:
The valve body can be made of either cast steel or stainless steel. In this case, ASME Class 150 is also available.

Secondary Set Pressure Range (Spring section) and Maximum Differential Pressure by Top Work Type Table

Nominal Diameter	Top Work Type and ΔP MAX (kPa)	Set Pressure Range (kPa)	1.0 or more – 1.5 or less	More than 1.5 – 2.0 or less	More than 2.0 – 3.0 or less	More than 3.0 – 5.0 or less	More than 5.0 – 7.0 or less	More than 7.0 – 10.0 or less	More than 10 – 15 or less	More than 15 or less	More than 15 or less	More than 15 or less
65	Top Work Type		A	B	B	B	C	C	D	D	E	E
	ΔP MAX.		150	130	200	340	300	430	420	500	500	500
80	Top Work Type		A	A	B	B	B	C	D	D	D	E
	ΔP MAX.		140	180	180	290	410	380	370	490	500	500
100	Top Work Type		A	A	A	B	B	C	C	C	D	D
	ΔP MAX.		110	140	220	240	330	300	460	500	500	500
125	Top Work Type		A	A	A	A	A	B	C	C	D	D
	ΔP MAX.		84	110	170	280	390	360	350	470	460	480
150	Top Work Type		A	A	A	A	A	B	C	C	D	D
	ΔP MAX.		68	90	140	230	310	290	280	380	370	390

Note:
By adding the maximum differential pressure (ΔP MAX) to the set pressure, the allowable maximum primary side pressure is obtained. However, the maximum allowable pressure for the secondary side is 500 kPa.
Example 1: If the nominal diameter is 100 and the set pressure is 10 kPa, adding the ΔP MAX from Top Work C results in a primary side pressure of 10 + 300 = 310 kPa.
Example 2: If the nominal diameter is 80 and the set pressure is 20 kPa, adding the ΔP MAX from Top Work D results in a primary side pressure of 20 + 490 = 510 kPa, which exceeds 500 kPa, so it becomes limited to 500 kPa.

Performance

Pressure Ratio	Varies depending on set pressure and top work type. (Refer to the “Secondary Set Pressure Range (Spring section) and Maximum Differential Pressure by Top Work Type” table above)
Offset	Less than 12% of the maximum set pressure
Closing Pressure Rise	Less than 20% of the maximum set pressure
Minimum Adjustable Flow Rate	Less than 5% of the rated flow rate
Valve Seat Leakage	Less than 0.5% of the rated flow rate

CV Value

Nominal Diameter	65	80	100	125	150
CV	35	46	72	123	178

Structure and Dimensions

Structure and Dimensions

(mm, kg)

Nominal Diameter		65	80	100	125	150
L		240	270	310	360	380
H1		141	146	173	203	222
H2		590	602	630	675	694
h3		248	260	288	333	352
Weight (kg)	Cast Iron	57	65	81	104	122
	Cast Steel	66	75	93	120	140

Note
(4) This shows the case for Top Work Type C.

Top Work Outer Diameter

(mm, kg)

Type		A	B	C	D	E
Outer Diameter		610	500	410	340	290
Weight Increase/Decrease (5)	Cast Iron	+27	+12	0	-7	-10
	Cast Steel	+31	+14	0	-8	-12

Note
(5) When the top work is other than type C, the values from the table above may be added or subtracted.