Rupture Pin Technology: How Rupture Pin Valves Work
A plain-language guide to Rupture Pin pressure relief and pressure isolation valves from Taylor Valve Technology: how the pin works, how the set pressure is fixed, how to choose a model and what to send us when you need one.
What Is a Rupture Pin Valve?
A Rupture Pin valve is a pin-operated valve that protects a system from excess pressure. A precision metal pin holds a piston in place, and that pin is both the pressure sensor and the actuator. It carries the force that system pressure puts on the piston. When that force reaches the set point, the pin gives way and the valve moves in milliseconds.
Rupture Pin valves come in two basic forms. Pressure relief valves stay closed and bubble-tight until the set point, then open to relieve pressure. Pressure isolation valves stay open in normal flow, then close at the set point to help protect downstream piping and equipment.
Rupture Pin is a brand of Taylor Valve Technology in Oklahoma City. Adaptive Industrial Solutions does not manufacture these valves. We help customers choose the right Rupture Pin model, set pressure, options and replacement pins and we handle the quote.
How a Rupture Pin Relief Valve Works
- System pressure acts on the piston. The piston pushes on the pin with a force equal to the pressure multiplied by the effective piston area.
- Below the set point the pin stays straight. The piston stays on its machined stainless-steel seat and the valve holds a bubble-tight seal.
- At the set point the pin gives way. The piston moves off the seat and the valve opens in milliseconds to relieve pressure.
- After the event a new pin is installed. The relief valves reseat without opening the line to atmosphere.
The pin sits outside the process, so it never touches the media. A stainless-steel safety cage is available to protect it from accidental damage, and an optional proximity sensor monitors the stem for remote open indication.
How fast is fast? In Rupture Pin Technology’s own test of a 1 in Model C valve set at 900 psig, the pin gave way fully in 1.7 milliseconds.
How a Rupture Pin Isolation Valve Works
Isolation valves turn the idea around. The pin holds the piston open, so product flows freely in normal service. When flowing pressure reaches the set point, the pin gives way and the piston closes for a bubble-tight seal. That isolates the pressure from downstream piping and equipment.
The Model JA ESV is an inline valve that is fully mechanical, with no need for electricity or pneumatics on site. The Model A ESV is an angle body valve that also closes if a downstream line breaks, because the flow itself drives the valve closed. Both offer an optional proximity sensor for remote closed indication.
Why the Pin Is So Precise: Euler’s Law
Each pin is a slender column sized by Euler’s Law for compressed columns. The force a pin can carry depends on three things: its diameter, its length and the stiffness of its alloy (the modulus of elasticity). Rupture Pin datasheets show the relationship. The force rises with the fourth power of the pin diameter and falls with the square of the pin length.
Because the force rises so steeply with diameter, small dimensions matter. According to Rupture Pin Technology’s Power of the Pin brochure, pins are ground to four or five decimal places and cut to an overall length accurate to 0.0005 in. Pin diameters range from 0.010 in to 1.250 in.
Temperature enters only through the alloy’s stiffness. The manufacturer uses three corrosion-resistant pin alloys and chooses one for the ambient conditions at the valve. The brochure states that with alloy #3 the stiffness varies no more than 0.3% from -100°F to +400°F ambient. The datasheets list the valves as unaffected by changing ambient temperature at the pin and by pulsating pressure.
Pins are also sized with the valve oriented as it will be installed, so the weight of the piston does not shift the set point.
How Each Valve Is Set and Tested
The set point is tuned in the valve itself. Starting from the Euler’s Law calculation, the factory adjusts the pin length through a series of test openings until the valve actuates at the required set pressure. It then confirms the setting with at least three more tests.
The Power of the Pin brochure describes three further checks on every valve: a bubble test of the body, a seat test of the piston’s Class VI seal and a shell test of sustained pressure integrity. Valves set above 3,000 psig are tested with water or another medium the customer specifies. Each valve ships with a signed test certificate.
Pins from each job are also tested in a Tinius Olsen compression tester and the results are archived. That record is what lets the manufacturer match replacement pins to the original valve.
Changing the Set Pressure and Ordering Replacement Pins
On a Rupture Pin valve the set pressure is changed by changing the pin. The POCO pin design keeps the overall pin assembly length the same for a given valve and varies the active length and diameter between end spacers, so one valve can take pins for several settings. The drilling valves, Models IC and HPRV, use color-coded POCO pins. The Model JA uses color-coded pins that match the top pin holding nut.
Every pin is labeled with its pin code, the valve serial number and the set pressure. The valve nameplate also carries the serial number, and the serial number is stamped on the bonnet in case the nameplate is lost. Each replacement pin is made for a specific valve, so always order by serial number. An optional pin holder keeps spare pins at the valve.
Need pins or O-rings? Send us a photo of the pin label or nameplate and we will request the right parts.
Rupture Pin Valves and Rupture Discs
Rupture discs and Rupture Pin relief valves are both non-reclosing pressure relief devices, but they work differently. A rupture disc sits in the flow path and must be replaced after it bursts, which means opening the line. A Rupture Pin valve keeps its pin outside the process. After it opens, the valve is reset by installing a new pin without opening the line to atmosphere.
Modern rupture discs are well-proven devices and the right choice depends on the service. Adaptive Industrial Solutions carries no rupture disc line, so we will tell you plainly where a pin fits and where it doesn’t.
To compare lifetime costs for your own application, try the Rupture Disc vs Rupture Pin Cost Calculator.
How to Select a Rupture Pin Valve
Start with these questions. If you don’t know an answer, mark it unknown and we will work through it with you.
- Relief or isolation: should the valve open to relieve pressure or close to isolate it?
- Set pressure and normal operating pressure.
- Process media, including solids, slurry or viscous fluids. Model CM has a flat piston with no voids for material to pack into, plus a flush port option.
- Temperature at the process and at the pin.
- Line size, connection type and flange rating.
- Back pressure. Model CC-ASME is downstream balanced, and a balanced piston option is available on Models C-ASME and D and on most Model CM sizes.
- Code requirements. Models CC-ASME and C-ASME are ASME UD-stamped.
- How the valve will be mounted, since pins are sized for the installed orientation.
- Remote indication with the optional proximity sensor.
| Model | Type | Published set range | Typical service |
|---|---|---|---|
| Model CC-ASME | Pressure relief, angle body, ASME UD-stamped | 15 to 1,480 psi | Code-governed liquid and air relief |
| Model C-ASME | Pressure relief, full bore angle body, ASME UD-stamped | 15 to 1,480 psi | Oil and gas, pipelines, chemical, wastewater, pulp and paper |
| Model D | Pressure relief, inline body | 5 to 2,000 psi | Chemical plants, refineries, pipelines, separators |
| Model CM | Pressure relief, angle body | 5 to 2,000 psi | Pulp, viscous fluids, steam-jacketed lines |
| Model H | High-pressure relief, angle body | Ask us | Methanol and chemical injection |
| Model IC | Drilling relief, angle body | Ask us | Mud and slurry pump systems |
| Model HPRV | Drilling relief, angle body | 7,000 to 15,000 psi | Frac fluid systems |
| Model JA ESV | Pressure isolation, inline body | Ask us | Meter houses, line transitions |
| Model A ESV | Pressure isolation, angle body | Ask us | Meter runs, meter houses |
Ranges are from the current Rupture Pin datasheets. Where Taylor Valve documents give different ranges for a model, we don’t publish a number. Instead we confirm the current range for your application.
Where Rupture Pin Valves Are Used
- Water and wastewater treatment: Models D and C-ASME are listed by the manufacturer for wastewater processing, including industrial wastewater.
- Chemical processing: Models D and C-ASME for process lines and vessels, Model H for high-pressure methanol and chemical injection and Model CC-ASME where a UD-stamped valve is required.
- Refineries and petrochemical plants: Model D for refineries, separators and pipelines, with Models C-ASME and CC-ASME for code-governed relief.
- Oil and gas production and midstream: relief valves for separators and pipelines plus isolation valves for meter runs, meter houses and line transitions.
- Drilling: Models IC and HPRV for mud, slurry and frac fluid systems.
- Pulp and paper: Model CM for pulp and viscous fluids and Models D and C-ASME for paper mills.
These are applications to evaluate, not blanket approvals. We confirm the fluid, solids, pressure, temperature, connections, materials and any code requirements before recommending a valve.
Rupture Pin Datasheets and Brochure
Every document opens straight away, with no form. More literature is in our Technical Resource Library.
- Rupture Pin Technology Overview Brochure (Get the Power of the Pin)Brochure
- Rupture Pin Model CC-ASME Relief Valve DatasheetDatasheet
- Rupture Pin Model C-ASME Relief Valve DatasheetDatasheet
- Rupture Pin Model D Relief Valve DatasheetDatasheet
- Rupture Pin Model CM Relief Valve DatasheetDatasheet
- Rupture Pin Model H Relief Valve DatasheetDatasheet
- Rupture Pin Model IC Drilling Relief Valve DatasheetDatasheet
- Rupture Pin Model HPRV Drilling Relief Valve DatasheetDatasheet
- Rupture Pin Model JA ESV Isolation Valve DatasheetDatasheet
- Rupture Pin Model A ESV Isolation Valve DatasheetDatasheet
Rupture Pin Technology FAQs
Is a Rupture Pin valve the same as a rupture disc?
No. Both are non-reclosing pressure relief devices, but a rupture disc sits in the flow path and is replaced after it bursts. A Rupture Pin valve keeps its pin outside the process and is reset with a new pin without opening the line to atmosphere. Adaptive Industrial Solutions carries no rupture disc line.
What does Euler’s Law have to do with Rupture Pin valves?
Euler’s Law describes the load a slender column can carry before it gives way. The force a Rupture Pin can hold depends on its diameter, its length and the stiffness of its alloy, so the manufacturer sizes each pin to give way at the valve’s set pressure.
Does temperature affect the set pressure?
The only temperature-sensitive factor in the pin calculation is the stiffness of the pin alloy. The manufacturer chooses the alloy for the ambient conditions at the valve, and the datasheets list the valves as unaffected by changing ambient temperature at the pin.
How fast does a Rupture Pin valve open?
The datasheets state that the valves open in milliseconds. In Rupture Pin Technology’s own test of a 1 in Model C valve set at 900 psig, the pin gave way fully in 1.7 milliseconds.
How do I order replacement Rupture Pins?
Order by valve serial number. It is on the pin label and the nameplate and it is stamped on the bonnet. Send a photo to sales@adaptiveind.com or call 877.818.5009 and we will handle the request.
Need help selecting a Rupture Pin valve?
Send us the set pressure, operating pressure, process media, temperature, line size and connection, back pressure and how the valve will be mounted, since pins are sized with the valve oriented as it will be in use. Tell us if the valve must be ASME UD stamped. Replacing a pin? Send a photo of the pin label; it shows the pin code, valve serial number and set point. Comparing with a rupture disc? We carry no rupture disc line, so we will tell you plainly where a pin fits and where it doesn't. If you don't know an answer, mark it unknown.
Request a Quote or Contact Adaptive
Adaptive Industrial Solutions1015 Grupp Road #31733
St. Louis, MO 63131
877.818.5009
sales@adaptiveind.com
www.adaptiveind.com