Parker U Series Root and Blowdown Valves

Severe-Service Needle Valves for Power Generation

Designed for demanding steam, high-temperature, and high-pressure applications. MCE provides local application support, direct Parker factory support, inventory options, and quote assistance.

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Parker and Motion & Control Enterprises

Power-Generation Valve Support from MCE
Motion & Control Enterprises serves customers through 45 U.S. facilities, 300+ technical sales reps, 215,000 product SKUs, 26 product categories, and 850 supplier partners. For Parker U Series root and blowdown valve applications, MCE offers:

  • Local application guidance
  • Direct Parker factory support
  • Inventory and stocking options
  • Vendor Managed Inventory programs
  • Quote and sourcing assistance
  • Specification and selection support

Parker U Series Severe-Service Needle Valves

u series valves

Parker U Series root and blowdown valves are union-bonnet needle valves designed for demanding power-generation instrumentation applications. They support root isolation and controlled blowdown in high-pressure, high-temperature, and steam service.

Up to 6,000 pounds per square inch gauge (psig)
For demanding instrumentation and process conditions.

Up to 1,200°F
Available with the high-temperature Grafoil packing option.

Sizes Through 1 Inch
Multiple connection, body material, and stem configurations are available.

A non-rotating lower stem helps reduce packing wear, while the union-bonnet design supports severe-service performance in power applications.

Discuss Your Application

Root Valve or Blowdown Valve?

Root Isolation-2

Root Isolation

Used to isolate a gauge, transmitter, or impulse line from the process. Selection depends on pressure, temperature, connection type, and the instrument being isolated.

Blowdown Service-2

Blowdown Service

Used to safely vent pressure, drain condensate, or clear an instrumentation line before testing or maintenance. Selection depends on the media, discharge requirements, pressure, temperature, and connection type.

Not sure which configuration fits your application? MCE can help review the service conditions and identify the appropriate Parker U Series valve.

Built for Demanding Power-Generation Applications

Parker U Series valves are designed for severe-service instrumentation applications where steam, high temperatures, and high pressures place added demands on valve performance.

Combined-Cycle Power Plants

Suitable for steam and instrumentation systems throughout combined-cycle facilities.

High-Temperature Steam Service

Available for temperatures up to 1,200°F with the high-temperature Grafoil packing option.

Pressure Instrumentation

Supports isolation and blowdown around gauges, transmitters, impulse lines, and other instrumentation connections.

TECHNICAL OVERVIEW

Parker U Series Specifications

Parker U Series union-bonnet needle valves are available in configurations designed for demanding pressure, temperature, and steam applications.

Valve type Union-bonnet needle valve
Body material 316 stainless steel
Available sizes Through 1 inch
Maximum pressure Up to 6,000 pounds per square inch gauge (psig) / 414 bar
Temperature range -65°F to 1,200°F / -54°C to 649°C
High-temperature configuration Grafoil® packing with high-temperature option
Stem design Non-rotating lower stem
Additional option Economical BD version available

Actual pressure and temperature ratings depend on the selected configuration and application conditions.

View Full Parker U Series Technical Catalog (PDF)

Cutaway illustration of a Parker U Series union-bonnet needle valve

Parker U Series Root and Blowdown Valve FAQs

What information is needed to select a Parker U Series valve?
Provide the intended service, operating pressure, operating temperature, process media, connection size and type, and any existing valve model or tag information. These details help MCE and Parker identify the appropriate configuration for the application.
What is the difference between a root valve and a blowdown valve?
A root valve isolates a gauge, transmitter, impulse line, or other downstream instrumentation from the process. A blowdown valve provides a controlled path for relieving pressure, draining condensate, or clearing an instrumentation line before testing or maintenance.
What pressure and temperature ratings are available?
Parker U Series valves are available in sizes through 1 inch, with pressure ratings up to 6,000 pounds per square inch gauge (psig), or 414 bar. With Grafoil® packing and the high-temperature option, the stated temperature range is -65°F to 1,200°F, or -54°C to 649°C. Actual ratings depend on the selected configuration.
Are Parker U Series valves available with high-temperature packing?
Yes. Parker offers U Series configurations with Grafoil packing and a high-temperature option for demanding power-generation applications.
Can MCE help identify a replacement for an existing valve?
Yes. Send MCE the existing model number, tag information, connection details, and operating conditions. MCE can review the information and work with Parker to identify an appropriate replacement or configuration.
Can MCE stock U Series valves for recurring demand?
MCE can discuss inventory, stocking, and Vendor Managed Inventory options based on recurring usage and anticipated demand. Availability and stocking arrangements depend on the required valve configuration and volume.
Does MCE provide Parker factory support for valve selection?
Yes. MCE provides local application guidance and can coordinate directly with Parker for product selection, specifications, and quote support.

Talk to an MCE Parker Valve Specialist

Need help selecting, sourcing, or replacing a Parker U Series root or blowdown valve? Share your application details, operating conditions, or existing valve information, and MCE will route your request to the appropriate specialist.
 
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