Need a process control valve but not sure whether to start with the least expensive two-way unit or spend up to the 3-way mixing models? The right choice depends on your piping, the medium you're controlling, and the duty you need the valve to perform. These four industrial valves split into two clear jobs: two-way normally closed control and three-way mixing. They also split by connection, with a manifold mount on one valve and a threaded port on another, and by condition, with open-box and used options in the mix.
Quick take
If you need a two-way valve rated to 350 PSI for steam, hot or cold liquids, air, or inert gas, the Sinclair Collins SC2000M is the least expensive pick at $159.95. For the threaded pneumatic option in bronze, the Schrader Bellows C064-4002 at $664.70 fits the middle. The two Powers Process Flowrite II valves are the 3-way mixing options; the one with "Heavy Duty Bronze" in the title costs $1,126.98, while the other is $1,220.98. Both Powers units are listed as used.
Comparison table
| Product | Function | Connection | Condition | Price | Price bar |
|---|---|---|---|---|---|
| Sinclair Collins SC2000M L234-1301 | 2-way normally closed | DN20 manifold, 1/2 in ports | New - Open box | $159.95 | |
| Schrader Bellows Sinclair-collins C064-4002 | Process control with pneumatic actuation | 1 in NPT | New - Open box | $664.70 | |
| Powers Process Flowrite II 593WM150STMS46RS | 3-way mixing 1-1/2 in | - | Used | $1,220.98 | |
| Powers Process Flowrite II Heavy Duty Bronze 593WM150STMS46RS | 3-way mixing 1-1/2 in | - | Used | $1,126.98 |
Decision matrix
| If your priority is... | Best fit | Why |
|---|---|---|
| Lowest-cost 2-way control | Sinclair Collins SC2000M | Two-way, normally closed, and sits at the bottom of the price range |
| Threaded pneumatic option | Schrader Bellows C064-4002 | Bronze process control valve with pneumatic actuation |
| 3-way mixing with explicit heavy-duty bronze wording | Powers Flowrite II Heavy Duty Bronze | Same model as the other Flowrite II but lower in price |
| 3-way mixing at the top of the price range | Powers Flowrite II | Carries the Flowrite II and 3-way mixing label without the heavy-duty bronze title |
Product notes
Sinclair Collins SC2000M Process Control Valve L234-1301
The SC2000M makes a strong case for the low end of the price range. It's a two-way, normally closed valve rated to 350 PSI, with a DN20 manifold mount and 1/2-inch ports. It is built around a 316L stainless steel body, a 303 stainless cylinder actuator, an anodized aluminum piston, and a floating PTFE seat. It is also one of two new open-box units here. The trade-off is the connection approach: if your installation expects a threaded pipe, this manifold-style valve won't match directly. The valve is designed for steam, hot or cold liquids, air, and inert gas, but the two-way normally closed operation is not a mixing function.
Schrader Bellows Sinclair-collins C064-4002 Process Control Valve
The C064-4002 is the threaded alternative in this set, with a 1-inch NPT connection, pneumatic actuation, and a bronze body. If your line is built around threaded pipe rather than a manifold block, this is the unit to consider. It's also new open box, so condition matches the SC2000M. On the downside, it sits in the middle of the price range, well above the manifold-mounted valve. And while this is a straightforward process control valve, the two Powers units are the 3-way mixing valves in this group, so mixing duty points toward them.
Powers Process Flowrite II Control Valve 3-Way Mixing 1-1/2
This Flowrite II is the higher-priced of the two Powers valves. It is a 3-way mixing valve in a 1-1/2-inch configuration and is listed as used. The model and MPN are the same as the Heavy Duty Bronze version, so the main practical difference is the price position and the lack of the heavy-duty bronze wording. Choose it if you want the 3-way mixing function and are comfortable with a used unit. The limitation is the cost: it is the most expensive option in this comparison. If the 3-way mixing function is what matters and the material label isn't a deciding factor, the other Flowrite II gives you the same model number at a lower price.
Powers Process Flowrite II Heavy Duty Bronze Control Valve
The Heavy Duty Bronze version of the same 593WM150STMS46RS model is priced below its stablemate while adding "Heavy Duty Bronze" to the name. That makes it the more descriptive pick if the valve body material matters to you. It's a 3-way mixing valve, listed as used, with the same model and MPN as the other Powers valve. The main limitation is that it's still a used unit, and it's the second most expensive option in this group. If you want a 3-way mixing valve and the heavy-duty bronze wording is a meaningful spec on your buy sheet, this is the one to choose.
Final recommendations by use case
- Lowest-cost two-way control: Sinclair Collins SC2000M. It pairs the low end of the price range with a normally closed two-way design.
- Threaded pneumatic option: Schrader Bellows C064-4002. It is the one valve in this group with a threaded mounting and pneumatic actuation.
- 3-way mixing with explicit material wording: Powers Process Flowrite II Heavy Duty Bronze. It carries the heavy-duty bronze label and sits below the other Flowrite II.
- 3-way mixing without the heavy-duty label: Powers Process Flowrite II. It has the same model number and MPN as the heavy-duty version but is the top-priced valve here.
