51 Series 1/4" to 3/4" Brass Needle Valves
The Ideal Valve Inc. 51 Series of Needle Valves are designed for precise flow of gases or liquids with pressures up to 3000 psi. These precision metering valves are for applications requiring metering of larger flows than those controlled by our standard 52 Series (Brass) and 54 Series (Stainless Steel).
Two models, 51-8-31E and 51-12-41E utilize a bar stock brass body. All other models use a cast bronze body. The following specifications apply to all of the above models. Every valve is factory tested to be leak-tight at 1100 psi.
Maximum Operating Pressure: 3000 psi (344.5 bar)
Operating Temperature Range: -65º to 450º F (-54º to 233º C)
• Packing seal is Teflon
• Needle is stainless steel
• Metal to metal seat
• 1.75" phenolic plastic knob
• Body, bonnet, and seat are bronze
• 22-24 turns from shutoff to full open
• 32 threads/inch for precision metering
Dimensions

Cv vs. No. Turns

Flow Characteristics of Models
| |
|
Cv (gpm) |
|
No. Turns Open |
51-4 |
51-6 |
51-8 |
1 |
0.02 |
0.07 |
0.13 |
2 |
0.05 |
0.14 |
0.33 |
3 |
0.09 |
0.22 |
0.48 |
4 |
0.12 |
0.30 |
0.62 |
5 |
0.16 |
0.35 |
0.73 |
6 |
0.19 |
0.41 |
0.82 |
7 |
0.21 |
0.48 |
0.91 |
8 |
0.23 |
0.52 |
1.01 |
9 |
0.27 |
0.57 |
10.6 |
10 |
0.30 |
0.61 |
1.09 |
Full Open |
0.38 |
0.67 |
1.18 |
Selction Guide
Item # |
Orifice |
Port |
Cv |
Max. A |
B |
Type |
Mounting Holes |
51-4-21 |
0.125 |
1/4" |
0.375 |
5.84 |
0.79 |
Straight Pattern |
N/A |
51-6-21 |
0.1875 |
1/4" |
0.67 |
5.84 |
0.79 |
Straight Pattern |
N/A |
51-6-23 |
0.1875 |
1/4" |
0.67 |
5.84 |
0.97 |
Mounting Flange
Straight Pattern |
10-32 |
51-6-24 |
0.1875 |
1/4" |
0.67 |
5.84 |
0.79 |
Straight Pattern |
N/A |
51-8-31E |
0.25 |
3/8" |
0.90 |
6.00 |
0.97 |
Straight Pattern |
N/A |
51-8-32 |
0.25 |
3/8" |
1.08 |
6.25 |
1.14 |
Angle Pattern |
N/A |
51-8-33 |
0.25 |
3/8" |
1.08 |
6.00 |
0.93 |
Mounting Flange
Straight Pattern |
10-32 |
51-12-41E |
0.375 |
1/2" |
2.65 |
7.00 |
1.1 |
Straight Pattern |
N/A |
51-14-61E |
.4375 |
3/4" |
3.10 |
7.25 |
1.1 |
Straight Pattern |
N/A |
|