BCST: Manufacturer of Zero-Leakage Triple Eccentric Butterfly Valves

When specifying a Triple Offset Butterfly Valve, trust is paramount. Every BCST valve is built to exceed industry standards in our ISO 9001 certified factory. We hold crucial certifications including API 609, API 607 Fire Safe, and CE, guaranteeing our products are suitable for the most demanding services in oil & gas, chemical processing, and power generation. This commitment to certified quality is a core advantage of partnering with BCST.

Comprehensive technical data and interactive tools to help you select the perfect valve for your application.

Material Selection Guide

Choose the right material for your application based on temperature, pressure, and media compatibility.

Dimensional Data

Interactive dimensional data table based on GB/T 12221-2005 standards.

DN	ضغط	Wafer Type (mm)	Flanged Type (mm)
DN50	PN 1.6~2.5	43	108
DN65	PN 1.6~2.5	46	112
DN80	PN 1.6~2.5	46	114
DN100	PN 1.6~2.5	52	127
DN125	PN 1.6~2.5	56	140
DN150	PN 1.6~2.5	56	140
DN200	PN 1.6~2.5	60	152
DN250	PN 1.6~2.5	68	165

Drive Type Selection

Choose the appropriate actuator type based on your operational requirements.

Manufacturing Standards & Certifications

BCST valves are manufactured according to international and Chinese national standards.

Selecting a triple offset butterfly valve for high-pressure or high-temperature service is a critical decision. But did you know that choosing the wrong body style can complicate installation, prevent necessary maintenance, and compromise safety?

The main types of triple offset butterfly valves are defined by their body construction: Lug, Wafer, Double Flanged, and Butt-Weld ends. The choice depends on your installation needs, pressure requirements, and whether the valve needs to serve as a dead-end isolation point.

I often discuss this with project engineers like Hassan. He views the valve body as more than just a pressure vessel; it’s a key part of the piping design. He once told me, “Emily, the valve’s performance is sealed by its triple offset geometry, but its function in the system is defined by its body style. Choosing a wafer style when you need end-of-line service is a fundamental design error.

This is because different body types interact with the pipeline flanges in very different ways. The right choice ensures not only a proper seal but also the safety and serviceability of the entire unit for years to come.

What is a Lug-Type Triple Offset Butterfly Valve?

Are you concerned about needing to perform maintenance on a pipeline without shutting down the entire system? A standard valve might not allow this, forcing a complete and costly outage for a simple repair on one section.

The Lug-type butterfly valve is the solution for this problem. Its body has threaded lugs that allow it to be bolted to one pipe flange at a time. This design allows it to be used for dead-end service, isolating the downstream piping for maintenance.

The key feature of a lug-style valve is the set of threaded inserts, or “lugs,” cast into the valve body. This allows you to connect the valve to each pipe flange with a separate set of bolts. In a standard installation, bolts will pass through both flanges and the valve. But the real advantage comes when you need to isolate a part of the system. You can remove the downstream piping while the valve remains bolted to the upstream flange, holding back the process fluid. This makes it invaluable for applications where regular maintenance is expected.

Hassan frequently specifies lug-style valves for utility connections and equipment tie-ins because they provide a safe and reliable point of isolation without needing a second valve, saving space and cost.

ميزة	الوصف
تصميم	Valve body has threaded lugs for bolting.
تثبيت	Can be bolted to each flange independently.
الميزة الرئيسية	Suitable for dead-end service and pipeline isolation.
الاستخدام الشائع	High-pressure applications; systems requiring frequent maintenance.

What is a Wafer-Type Triple Offset Butterfly Valve?

Are you looking for a more compact and cost-effective valve for a straightforward isolation task? A heavier or more complex valve might be overkill, taking up unnecessary space and budget in your piping design.

The wafer-type butterfly valve is a compact and lightweight option that is “sandwiched” between two pipe flanges. It relies on long through-bolts that clamp the entire assembly together, making it a simple, space-saving, and economical choice for many applications.

A wafer valve is the essence of simplicity. It has no lugs; instead, it has alignment holes and is held in place by the compression of the flange bolts that extend from one flange to the other, clamping the valve in between. This design makes the valve lighter and often more affordable than a lug-style valve. Because of its slim profile, it is an excellent choice for systems where space is tight.

However, this design has a significant limitation: it cannot be used for dead-end service. If you need to remove the downstream piping, there is nothing to hold the valve in place, and you would need to shut down the entire line. I see these valves used extensively in long, straight pipe runs where isolation for maintenance isn’t a primary concern, such as water distribution or HVAC systems.

ميزة	الوصف
تصميم	A thin body held between two pipe flanges by through-bolts.
تثبيت	“Sandwiched” between pipe flanges.
الميزة الرئيسية	Lightweight, compact, and cost-effective.
Limitation	Cannot be used for dead-end service.

When Do You Need a Double Flanged or Welded Valve?

Are you dealing with very large pipe sizes or extremely high pressures where lug and wafer styles may not be suitable? In these critical service conditions, ensuring a robust and secure connection is the highest priority.

For very large diameters or critical, high-pressure applications, double flanged and butt-weld end valves provide the most rigid and secure connection. A double flanged valve bolts independently to each pipe flange, while a butt-weld valve becomes an integral, leak-free part of the pipeline.

These styles are for the most demanding jobs. A double flanged valve has two sets of flanges as part of the valve body itself. Each valve flange is bolted to its corresponding pipe flange with its own set of bolts. This creates an extremely strong and rigid connection, often preferred for very large and heavy valves. It also allows for dead-end service, similar to a lug valve.

Butt-weld end valves take this a step further. These valves have no flanges at all. Instead, the ends of the valve are beveled and are welded directly to the ends of the pipe. This creates a completely leak-proof, continuous connection that is as strong as the pipe itself. Hassan specifies butt-weld valves for the most critical, high-temperature, and high-pressure steam services where zero leakage and maximum structural integrity are non-negotiable.

Body Style	الوصف	الأفضل لـ
Double Flanged	Valve has its own flanges that bolt to pipe flanges.	Very large pipe sizes, high-pressure applications.
Butt-Weld	Valve ends are welded directly to the pipeline.	Highest integrity applications, steam, zero-leakage requirements.
Top-Entry	Allows access to valve internals from the top.	Critical applications where inline maintenance is required.

خاتمة

Choosing the right triple offset butterfly valve body is crucial for system performance. Use lug-style for dead-end service, wafer-style for compact and cost-effective needs, and double flanged or butt-weld for the most critical, high-pressure applications.