The Armstrong GD-10 and GD-10F are lightweight direct-acting diaphragm valves used primarily for pneumatic tool air supply and non-hazardous gas regulation. Screwed connections make it easy to support in position without external sensing lines or other parts. Zinc or aluminum bodies eliminate rust and scale. The plug, seat, and diaphragm are renewable in-line, and quick adjustments can be made externally with a locking handle. A quarter-inch pressure gauge connection is standard, and all units are capable of tight shutoff for dead-end service.

The GD-10 is available in sizes 1/4" - 2". Highly efficient Model AF-10 air filters with zinc or aluminum bodies are used to remove liquids and solid particles from compressed air. The AF-10 is available in sizes 1/4" - 1".

Specifications

GD-10/GD-10F/AF-10 Specifications
Model	Application	Inlet Pres. psig (bar)	Reduced Pressure psig (bar)	Min. Differ. psig (bar)	Max. Temp. °F (°C)	Materials
						Body in (mm)	Bowl	Main Valve in (mm)	Valve Plug in (mm)	Diaphragm
GD-10	Air and Other Non-Corrosive Gases	15 - 300 (1 - 20)	5 - 125 (.34 - 8.6)	7 (.48)	175 (79)	Zinc 1/4, 3/8, 1/2, 3/4 (6, 9, 15, 20) Aluminum 1 - 2 (25 - 50)	—	Zinc 1/4, 3/8, 1/2, 3/4 (6, 9, 15, 20) Aluminum 1 - 2 (25 - 50)	Brass 1/4, 3/8, 1/2, 3/4 (6, 9, 15, 20) Nylon 1 - 2 (25 - 50)	Nitrile
GD-10F		15 - 250 (1 - 17)	5 - 125 (.34 - 8.6)	7 (.48)		Zinc			Brass	Nitrile
AF-10		0 - 250 (0 - 17)	—	—		Zinc 1/4, 3/8, 1/2, 3/4 (6, 9, 15, 20) Aluminum 1 (25)		—	—	—

Dimensions and Weights

Symbol	Connection Size
	in	mm	in	mm	in	mm	in	mm	in	mm	in	mm
	1/4	8	3/8	10	1/2	15	3/4	20	1, 1-1/4, 1-1/2	25, 32, 40	2	50
L	2-5/8	67	2-5/8	67	2-5/8	67	3-1/2	98	4-1/4	108	6	152
H	5-3/8	136	5-3/8	136	5-3/8	136	5-7/8	149	7-1/8	181	9-3/4	248
H1	1-1/2	38	1-1/2	38	1-1/2	38	1-1/2	38	2-3/8	60	3-9/16	90
Wt, lb (kg)	1-1/2 (.7)		1-1/2 (.7)		1-1/2 (.7)		2 (.9)		3 (1.4)		10 (4.5)
Cv	1.4						2.6		5.8		43

INFO

** 2" (50 mm) GD-10 valve maximum inlet pressure is 425 psi (30 bar). † GD-10F has a maximum inlet pressure of 250 psi (17 bar).

GD-10F Dimensions and Weights
Symbol	Connection Size
	in	mm	in	mm	in	mm	in	mm
	1/4	8	3/8	10	1/2	15	3/4	20
L	2-3/4	70	2-3/4	70	2-3/4	70	3-7/8	98
H	9-3/8	238	9-3/8	238	9-3/8	238	10-7/8	276
H1	5-3/4	146	5-3/4	146	5-3/4	146	6-3/8	162
Wt, lb (kg)	2-1/2 (1.2)		2-1/2 (1.2)		4-1/2 (2.0)		4-1/2 (2.0)
Cv	1.4						2.6

AF-10 Dimensions and Weights
Symbol	Connection Size
	in	mm	in	mm	in	mm	in	mm	in	mm
	1/4	8	3/8	10	1/2	15	3/4	20	1	25
L	2-3/4	70	2-3/4	70	2-3/4	70	3-7/8	98	4-3/4	121
H	6-3/8	162	6-3/8	162	6-3/8	162	7	178	11-3/8	289
H1	5-3/4	146	5-3/4	146	5-3/4	146	6-3/8	162	10	254
Wt, lb (kg)	2 (.9)								3 (1.4)

Capacities — Air

GD-10/GD-10F Capacities—Air
scfm							m³/hr
Inlet	Outlet	Connection Size					Inlet	Outlet	Connection Size
		in							mm
psig		1/4, 3/8, 1/2	3/4	1*, 1-1/4, 1-1/2	2**		bar		8, 10, 15	20	25*, 32, 40	50**
15	8	19	35	78	580		1.0	0.6	32	60	133	985
30	23	24	44	98	727		2.0	1.6	40	75	167	1,235
	15	33	61	136	1,011			1.0	56	104	232	1,718
	5 - 7	38	70	157	1,166			.34 - 48	64	120	267	1,981
40	33	26	49	109	810		2.8	2.3	45	83	186	1,377
	20	42	77	173	1,280			1.4	71	131	293	2,174
	5 - 12	46	86	192	1,427			.34 - .83	79	147	327	2,424
50	40	34	63	141	1,046		3.4	2.8	58	107	240	1,777
	30	46	86	191	1,416			2.1	78	145	324	2,405
	5 - 17	55	102	228	1,687			.34 - 1.17	93	173	387	2,867
75	60	49	91	203	1,503		5.2	4.1	83	154	344	2,553
	45	66	123	273	2,026			3.1	112	208	464	3,442
	7 - 30	76	141	316	2,339			.48 - 2.1	129	240	536	3,975
100	80	64	118	264	1,958		6.9	5.5	108	201	449	3,327
	60	86	159	355	2,634			4.1	146	271	604	4,475
	10 - 42	97	181	403	2,991			.69 - 2.9	165	307	686	5,082
125	100	79	146	326	2,413		8.6	6.9	134	248	553	4,101
	75	106	196	437	3,241			5.2	179	333	743	5,507
	13 - 55	119	220	491	3,643			.89 - 3.8	202	374	835	6,190
150	120	93	173	387	2,868		10.3	8.3	159	295	657	4,873
	85	129	240	535	3,967			5.9	219	408	909	6,741
	15 - 67	140	260	579	4,295			1.03 - 4.6	238	441	984	7,298
175	125	126	235	524	3,884		12.1	8.6	215	399	890	6,599
	100	149	276	617	4,573			6.9	253	470	1,048	7,769
	18 - 80	161	299	667	4,947			1.24 - 5.5	274	508	1,134	8,405
200	125	161	298	666	4,934		13.8	8.6	273	507	1,131	8,383
	20 - 92	182	339	755	5,599			1.38 - 6.3	310	575	1,283	9,513
250†	25 - 125	225	417	931	6,903		17.2†	1.7 - 8.6	382	709	1,582	11,729
300	30 - 125	267	496	1,107	8,207		20.0	2.1 - 8.6	454	843	1,881	13,944
350**	35 - 125	—	—	—	9,511		24.1**	2.4 - 8.6	—	—	—	16,159
425**	43 - 125	—	—	—	11,467		29.3**	3.0 - 8.6	—	—	—	19,482

INFO

GD-10F is not available above 3/4" (20 mm).

Typical Piping

Typical Piping For Air

Typical Piping For Steam

Start-Up and Adjusting Procedures

WARNING

Improper adjustment of the pressure reducing valve may cause hunting, scale problems, etc., and damage to the valve itself.

Adjust the valve as follows:

1. Close the gate valves before and after the pressure reducing valve. Open the globe valve in the bypass line and blow down the inlet piping. Adjust the opening of the bypass valve so that the safety valve if used does not blow. After blowing the system down, close the bypass valve.
2. Loosen the lock nut and adjusting screw to relieve the adjusting spring.
3. Slowly open the inlet side gate valve to the fully open position, and partially open the outlet valve so only a small amount of fluid can pass.
4. Slowly turn the adjusting screw clockwise until the desired pressure is obtained on the downstream pressure gauge.
5. Slowly open the outlet valve to the fully open position.
6. After adjustment, fasten the lock nut.

Troubleshooting Guide

Problem	Cause	Solution
The desired pressure cannot be obtained	The inlet pressure is not suitable.	Change the pressure to the appropriate level.
	The valve size is excessively smaller than what is required.	Change to the appropriate size.
	The inlet strainer is clogged by a foreign substance.	Disassemble and clean the strainer.
	The pressure gauge is out of order.	Replace the gauge.
The outlet pressure rises higher than the specified pressure.	The valve and the valve seat are clogged by a foreign substance.	Disassemble and clean the valve seat.
	The "O" ring is damaged.	Replace the "O" Ring.

Maintenance and Disassembly

Disassembly of Body Turn the valve guide counterclockwise and remove it from the body. Pull out and remove the valve and spring.

Disassembly of Diaphragm

1. Slightly loosen the lock nut (16) and turn the handle counterclockwise to unload the adjusting spring (17).
2. Remove the lock nut (16) and remove the bonnet from the body (1). Pull out and remove the top spring plate (6), adjusting screw (15), and diaphragm (19).

Notes To Reassemble

1. Check to be sure the disc (9) and the seat (12) are not flawed.
2. Apply grease to the "O" ring (27).
3. Attach the diaphragm (19) to the specified location without twisting.