High Pressure High Temperature DN20-250 Spring Slightly Opened Closed Safety Valve for Industrial Use

Product Description

Product Description

A safety valve is an indispensable overpressure protection device widely applied in industrial pipelines, pressure vessels, boilers, and various process systems. Designed with a spring-loaded mechanism as its core driving force, it operates automatically based on preset pressure thresholds—when the system pressure exceeds the designated safe value, the valve disc is pushed open by the medium pressure to rapidly release excess fluid or gas, effectively reducing the internal pressure to a safe range. Once the pressure drops below the set level, the spring force promptly resets the valve disc to achieve reliable sealing, preventing medium leakage.

Available in multiple materials such as cast steel (WCB), stainless steel (304/316L), and alloy steel, safety valves can be customized to suit different working conditions including high temperature, high pressure, and corrosive media. They are categorized into full-lift and low-lift types based on structural design, and flanged or threaded connection types for easy installation. Beyond overpressure relief to avoid equipment explosion or damage, safety valves also play a key role in stabilizing system pressure, ensuring the smooth operation of production processes, and preventing secondary hazards like environmental pollution or safety accidents caused by medium leakage.

Compliant with international standards such as ASME and DIN, our safety valves feature robust construction, precise pressure control, and long-term reliability. They are essential safety guarantees for industries including chemical engineering, energy, power generation, petroleum, and water treatment, providing comprehensive protection for industrial production safety and equipment integrity.

Product Advantages

Automatic overpressure relief: Triggers instantly when system pressure exceeds the set value, no manual intervention required, ensuring real-time protection.

Reliable sealing performance: Tight closure after pressure recovery, effectively preventing leakage of media (gas, liquid) and reducing safety risks.

Strong adaptability: Compatible with various materials (cast steel, stainless steel, alloy steel) and working conditions (high temperature, high pressure, corrosive media).

Compact & easy to install: Space-saving structure, supports flanged/threaded connections, simplifying on-site installation and layout.

Stable pressure regulation: Maintains system pressure within a safe range, guaranteeing smooth operation of production processes.

Low maintenance cost: Robust construction with wear-resistant components, reducing frequency of repairs and downtime.

Compliance with international standards: Meets ASME,  DIN, and other global norms, ensuring interchangeability and reliability.

Long service life: Resists harsh industrial environments (corrosion, vibration, high temperature), delivering consistent performance over time.

Versatile applications: Suitable for boilers, pressure vessels, pipelines, and industries like chemical, energy, petroleum, and power generation.

Precise pressure control: Adjustable spring preload allows accurate setting of opening pressure, matching specific system requirements.

How does valve work?

The operation of a safety valve follows a core logic of "preset pressure triggering → automatic pressure relief → reset after pressure recovery". Taking the most commonly used spring-loaded safety valve as an example, the specific working process is as follows:

1. Initial Sealed State (Normal Working Condition)
The safety valve uses the preload force of the spring to press the valve disc tightly against the valve seat, forming a tight seal. The preload force of the spring corresponds to the "safe pressure value" of the system, which is preset by the adjusting nut. When the medium pressure in the system is normal (lower than the spring preload force), the valve disc remains closed, preventing medium leakage.

2. Overpressure Opening & Pressure Relief (Abnormal Working Condition)
When the medium pressure in the system rises and exceeds the preset safe value, the upward thrust of the medium on the valve disc will be greater than the spring preload force. The valve disc is pushed open, the valve activates, and the excess medium is quickly discharged through the valve seat flow channel and discharge port, resulting in a gradual drop in system pressure.

3. Reset After Pressure Recovery (Return to Normal Condition)
As the medium continues to be discharged, the system pressure gradually decreases to below the preset safe value. At this point, the spring preload force is again greater than the medium's thrust on the valve disc. The spring pushes the valve disc to re-seat tightly against the valve seat, the valve closes, and the seal is restored, allowing the system to operate normally.

Core Design Logic
Trigger mechanism: Fully relies on the balance between pressure difference and spring force, requiring no manual operation. It achieves automatic control of "opening immediately when overpressured and closing when pressure drops".

Adaptive scenarios: Safety valves of different structures (full-lift/low-lift) adjust the discharge capacity after opening through valve disc design, adapting to different working conditions such as low-pressure small-flow and high-pressure large-flow.

Parameters

Basic Specifications    
Nominal Diameter (DN)    e.g., DN15, DN25, DN50, DN80, DN100
Nominal Pressure (PN)    e.g., PN10, PN16, PN25, PN40, PN64
Pressure Class    e.g., Class 150, Class 300, Class 600, Class 900
Set Pressure (Relief Pressure)    Preset pressure for valve activation (e.g., 1.6MPa, 2.5MPa)
Temperature Range    Operating temperature limit (e.g., -29℃~425℃, -40℃~550℃)
Medium    Compatible media (e.g., Steam, Water, Oil, Chemical Fluid, Gas)

Performance Parameters    
Maximum Allowable Working Pressure (MAWP)    Maximum pressure the valve can withstand under normal conditions
Discharge Capacity (Cv/Kv Value)    Flow capacity of the valve (e.g., Cv=5.0, Kv=4.2)
Opening Type    Full Lift / Low Lift
Closing Pressure    Pressure at which the valve disc reseats after relief
Leakage Class    e.g., Class IV, Class V, Class VI 
Operating Pressure Range    Working pressure scope of the system (e.g., 0.5MPa~1.6MPa)

Structure & Installation    
Body Material    e.g., WCB, CF8 (304SS), CF8M (316SS), Alloy Steel, Monel
Trim Material (Disc/Seat)    e.g., 304SS, 316SS, Stellite, PTFE (soft seal)
Connection Type    Flanged (PN/Class), Threaded (NPT/BSP), Welded (Butt Weld/Socket Weld)
Operation Type    Spring Loaded, Pilot Operated
Seat Type    Soft Seal, Metal Seal
Weight & Dimension (L×W×H)    Overall weight and physical size (e.g., 15kg, 250×180×320mm)

Connection Type	Flange
Max. Operating Pressure	PN40
Max. Operating Temperature	300 DegreeC
media	Oil,air,water
port size	DN20-250
structure	Safety
place of origin	China
	Jiangsu
application	General
customized support	OBM, ODM, OEM
power	Other
model number	SaV-2501
brand name	Yoonad
Flow Rate - Maximum
Inlet Connection Size	1 in
Mounting Orientation	Horizontal, Vertical
Sealing Material	Epdm, FKM, Metal, PVC
temperature of media	High Temperature, Low Temperature, Medium Temperature, Normal Temperature
warranty	2 years
Type	Safety Relief Valves
Usage	Pressure Pipe Equipment
Size	DN20-250
Connection	Flange Ends
MOQ	1 Piece
Working Pressure	PN16-40
Packing	Wooden Box
Design	Custom Produce
Medium	Water,oil,gas
Payment	30% TT