HDPE хоолойн хэмжээ ба хэмжээсийн гарын авлага: Диаметр, SDR, Даралтын үнэлгээ ба сонгох зөвлөмжүүд

Өндөр нягтралтай полиэтилен (HDPE) хоолой are widely used in water supply, усалгаа, уул уурхай, үйлдвэрлэлийн шугам хоолой, and municipal infrastructure because of their excellent durability, зэврэлтэнд тэсвэртэй, мөн урт хугацааны үйлчилгээний хугацаа.

Гэсэн хэдий ч, зөвийг сонгох HDPE pipe size is not only about choosing a diameter. Engineers and project managers need to consider multiple factors, including pipe dimensions, хананы зузаан, SDR үнэлгээ, даралтын шаардлага, and installation conditions.

HDPE pipe sizes are available in a wide range of diameters and specifications to meet different application requirements. Choosing the right specification ensures sufficient flow capacity, reliable pressure performance, and long-term operational stability.

This guide explains the key factors affecting HDPE pipe dimensions, орно:

• Common HDPE pipe diameter sizes
• Outside diameter and inside diameter
• Wall thickness requirements
• SDR ratings and pressure classes
• How to select the right HDPE pipe size for different applications

Whether you are designing a water supply system, agricultural irrigation project, or industrial pipeline, understanding HDPE pipe specifications helps avoid incorrect selection and improves overall system efficiency.

HDPE Pipe Sizes and Dimensions

Understanding HDPE Pipe Sizes and Dimensions

Before diving into specific sizes and charts, it’s essential to understand how HDPE pipes are dimensioned. Unlike steel pipes, which use the Nominal Pipe Size (NPS) system—a label that no longer matches any actual dimension—HDPE pipes areoutside-diameter controlled.

This means the outside diameter (OF) is the fixed reference. А 110 mm HDPE pipe really is 110 mm across the outside, every time, regardless of wall thickness or pressure class. Холбох хэрэгсэл, хайлуулах машинууд, and tapping tools all register on that OD, which is why getting the OD system right matters more than any other single number.

Key Dimension Parameters

Параметр	Утга
Нэрлэсэн хэмжээ (Д.Н)	The designated size, typically matching the outside diameter in millimeters
Гаднах диаметр (OF)	The actual external diameter of the pipe—the fixed reference dimension
Дотоод диаметр (ID)	The internal bore; varies with wall thickness
Ханын зузаан	The thickness of the pipe wall; determines pressure capacity
SDR үнэлгээ	Standard Dimension Ratio—OD divided by wall thickness
Даралтын үнэлгээ (PN)	The nominal pressure the pipe can handle

HDPE pipes Pressure vs. Flow

Common HDPE Pipe Diameter Sizes Chart

The following HDPE pipe size chart covers the most commonly used HDPE pipe diameter sizes in global markets. These dimensions generally follow ISO 4427 болон EN 12201 стандартууд, though slight variations may exist between manufacturers.

Common HDPE Pipe Sizes

Нэрлэсэн диаметр (Д.Н)	Гаднах диаметр (OF)	Ердийн програмууд
20 мм	20 мм	Small water systems, household connections
25 мм	25 мм	Garden irrigation, minor distribution
32 мм	32 мм	Drip irrigation systems, landscape watering
40 мм	40 мм	Small-scale agricultural pipelines
50 мм	50 мм	Agricultural pipelines, small water networks
63 мм	63 мм	Усны хуваарилалт, rural supply
75 мм	75 мм	Medium irrigation, building supply
90 мм	90 мм	Аж үйлдвэрийн хэрэглээ, factory water lines
110 мм	110 мм	Хотын усан хангамж, ариутгах татуурга
125 мм	125 мм	Medium municipal networks
160 мм	160 мм	Large pipelines, main distribution
200 мм	200 мм	Municipal trunk lines, industrial projects
250 мм	250 мм	Major water transmission
315 мм	315 мм	Bulk water supply, уул уурхайн үйл ажиллагаа
400 мм+	400 мм+	Large-scale industrial and municipal projects

Small-Diameter Pipes (DN20–DN63)：

• Residential plumbing：Household water pipes and courtyard water supply
• Drip and sprinkler irrigation：Precision agriculture is the first choice
• Landscape and gardening：Greenbelt irrigation system

Medium-Diameter Pipes (DN75–DN160) ：

• Municipal water distribution：Urban water supply branch network
• Industrial process water：Factory internal circulating water system
• Sewerage and drainage：Gravity flow and pressure flow drainage systems

Large-Diameter Pipes (DN200+) ：

• Municipal trunk mains：Long-distance water conveyance and raw water transportation
• Аж үйлдвэрийн шугам хоолой：Chemical and power cooling water systems
• Уул уурхайн зутан тээвэрлэх：Excellent wear resistance
• Marine outfalls：Corrosion resistant and flexible to adapt to seabed topography

Дотоод холбоос：

• For agricultural applications, манай гарын авлагыг үзнэ үү Хөдөө аж ахуйн усалгааны хоолой
• For industrial specifications, visit Industrial HDPE Pipes

HDPE Pipes in Modern Agricultural Irrigation

HDPE Pipe Wall Thickness and SDR Explained

One of the most critical yet misunderstood aspects of HDPE pipe dimensions нь Стандарт хэмжээсийн харьцаа (SDR). The SDR defines the relationship between the pipe’s outside diameter and its wall thickness, and it directly determines the pipe’s pressure capability.

What is SDR?

SDR = Outside Diameter (OF) / Ханын зузаан

Жишээ нь, a pipe with an OD of 110 mm and a wall thickness of 10 mm has an SDR of 11.

The Inverse Relationship ：

Lower SDR value → Thicker wall → Higher pressure capacity → Smaller inner diameter & Lower flow rate

Higher SDR value → Thinner wall → Lower pressure capacity → Larger inner diameter & Higher flow rate

Relationship Between SDR and Wall Thickness

SDR үнэлгээ	Ханын зузаан	Pressure Capability	Ердийн хэрэглээ
SDR 9	Very thick	Very high	High-pressure industrial
SDR 11	Зузаан	Өндөр	Усан хангамж, gas distribution
SDR 13.6	Medium-thick	Medium-high	General water systems
SDR 17	Дунд зэрэг	Дунд зэрэг	Усжуулалт, ус зайлуулах хоолой
SDR 21	Нимгэн	Бага	Бага даралттай ус зайлуулах хоолой
SDR 26	Very thin	Маш бага	Non-pressure applications
SDR 33	Ultra thin	Minimal	Кабелийн хамгаалалт

SDR11 vs SDR17 — A Practical Comparison：

Онцлог	SDR 11	SDR 17
Ханын зузаан	Зузаан	Thinner
Даралтын үнэлгээ	PN16 (илүү өндөр)	PN10 (lower)
Weight per meter	Heavier	Lighter
Cost per meter	Илүү өндөр	Доод
Flow Capacity	Доод (smaller ID)	Илүү өндөр (larger ID)
Ердийн хэрэглээ	Хотын ус, өндөр даралттай	Усжуулалт, ус зайлуулах хоолой

Гол ойлголт：

Many buyers mistakenly believe that a larger pipe diameter means higher pressure capacity. Гэсэн хэдий ч, pressure capability is determined by the SDR value (the ratio of wall thickness to outside diameter), rather than the diameter alone. A DN400 SDR33 pipe, жишээ нь, has a much lower pressure rating than a DN90 SDR11 pipe.

Дотоод холбоос：

• For a detailed comparison, манай нийтлэлийг уншина уу SDR11 болон SDR17 HDPE хоолой

HDPE Pipe Wall Thickness between SDR11 and SDR17

HDPE Pipe Pressure Rating and PN Classes

HDPE хоолойн даралтын үзүүлэлт is the maximum allowable operating pressure that a pipe can withstand continuously at a specified temperature (usually 20°C). In the HDPE industry, pressure ratings are commonly expressed using PN classes (Pressure Nominal).

HDPE хоолойн даралтын үнэлгээний гарын авлага

Даралтын ангилал	Ажлын хамгийн их даралт	Ердийн програмууд
PN 6	6 баар (0.6 МПа)	Бага даралттай ус зайлуулах хоолой, gravity sewers
PN 8	8 баар (0.8 МПа)	Storm water, low-pressure irrigation
PN 10	10 баар (1.0 МПа)	Ерөнхий усан хангамж, agricultural systems
PN 12.5	12.5 баар (1.25 МПа)	Аж үйлдвэрийн шугам хоолой, medium-pressure water
PN 16	16 баар (1.6 МПа)	Өндөр даралтын усан хангамж, gas distribution
PN 20	20 баар (2.0 МПа)	Very high-pressure industrial systems
PN 25	25 баар (2.5 МПа)	Extreme pressure applications

Relationship Between PN and SDR：

PN Class	Ердийн SDR	Common PE Grade
PN 6	SDR 26	PE80, PE100
PN 8	SDR 21	PE80, PE100
PN 10	SDR 17	PE80, PE100
PN 12.5	SDR 13.6	PE100
PN 16	SDR 11	PE100
PN 20	SDR 9	PE100
PN 25	SDR 7.4	PE100

Factors Affecting Pressure Rating：

1. Operating Temperature
   • Standard pressure ratings are based on 20°C. For every 10°C increase in temperature, the pressure-bearing capacity decreases by approximately 10%.
   • At 30°C, a PN16 pipe effectively becomes a PN14.4 pipe.
   • In high temperature environments (such as tropical areas or industrial hot water), a higher PN level must be selected or temperature correction must be performed.
2. Safety Factor
   • A safety factor of 1.25 руу 1.5 is typically used in design.
   • For critical applications (such as gas delivery), a safety factor of 2.0 or higher may be required.
3. Cyclic Loading
   • Systems with frequent pressure fluctuations (such as pump stations with severe water hammer) require additional consideration of fatigue factors.
   • HDPE materials have good fatigue resistance, but a margin should still be allowed when selecting a material.
4. Pipe Material Grade
   • The minimum required strength (Хатагтай) of PE100 is 10 МПа, which is better than PE80’s 8 МПа.
   • Under the same SDR, the PN grade of PE100 pipe is higher than that of PE80.

Дотоод холбоос：

• For comprehensive pressure guidance, манайхыг үзнэ үү HDPE хоолойн даралтын үнэлгээний гарын авлага

HDPE Pipe Sizes and Dimensions

How to Choose the Right HDPE Pipe Size

This section represents the highest commercial value of the article. Selecting the correct HDPE pipe size is not about picking the cheapest option — it is about matching engineering requirements with material capabilities.

Алхам 1: Determine Required Flow Rate

Flow rate (Q) is the starting point for selection. Based on the design flow rate, the minimum required inner diameter can be deduced.

Basic Formula：

Q = A × v

Where: Q = Flow rate (m³/s) = Cross-sectional area (м²)= π × (ID/2)² v = Flow velocity (м/с)

Recommended Flow Velocities：

Өргөдөл	Recommended Velocity
Усан хангамж	0.5 – 2.0 м/с
Усжуулалт	0.3 – 1.5 м/с
Sewerage	0.6 – 2.5 м/с
Будаг	1.0 – 3.0 м/с
Industrial process	0.5 – 3.0 м/с

Practical Tip：

Too low a flow velocity (<0.3 м/с) may lead to the deposition of suspended solids; too high a flow velocity (>3 м/с) will exacerbate pipe wall wear and the risk of water hammer. For long-distance water transmission, it is recommended to use a value in the range of 1.0–1.5 m/s to balance energy consumption and pipeline cleanliness.

Алхам 2: Check Operating Pressure

After determining the pipe diameter, it is necessary to check whether the pressure-bearing capacity of the pipe material meets the maximum working pressure of the system.

Pressure Check Formula：

PN_selected ≥ P_max × Safety Factor

Where：

• P_max = Maximum operating pressure including surge / Maximum working pressure (including water hammer)
• Safety Factor = Typically 1.25–1.5 for water

Жишээ：If a water system has a normal pressure of 8 bar and potential water hammer of 3 баар, the maximum pressure is 11 баар. With a safety factor of 1.25, the required PN is 13.75 → Select PN16 (SDR11).

Дотоод холбоос：

• For detailed pressure calculations, refer to our HDPE хоолойн даралтын үнэлгээний гарын авлага

3. Consider Installation Conditions

Installation environment significantly impacts pipe selection:

Нөхцөл байдал	Анхаарах зүйл
Underground installation	Soil loads, burial depth, traffic loading
Above-ground installation	Хэт ягаан туяанд өртөх (requires protection), thermal expansion
Температур	Derate pressure rating for temperatures above 20°C
Soil conditions	Rocky soil may require thicker walls or sand bedding
Газар хөдлөлтийн бүсүүд	HDPE’s flexibility is an advantage, but wall thickness may need adjustment

Temperature Considerations：

• High ambient temperature：To reduce pressure resistance, the PN rating needs to be upgraded.
• Low ambient temperature：HDPE becomes brittle, requiring extra care during handling and bending.
• Fluid temperature：When supplying hot water, the derating must be strictly followed according to the temperature correction factor.

Дотоод холбоос：

• For installation best practices, үзнэ үү HDPE хоолойг газар доор хэрхэн суурилуулах вэ

Install HDPE Pipes Underground

Алхам 4: Match Pipe Size With Application

Different application scenarios have different requirements for pipe size and performance.

Application-Based HDPE Pipe Selection

Өргөдөл	Гол анхаарах зүйлс	Recommended SDR/PN	Тэмдэглэл
Хөдөө аж ахуйн усалгаа	Flow capacity, cost efficiency	SDR17 (PN10) / SDR11 (PN16) for pressurized systems	Prioritize SDR17 for gravity; SDR11 for pump systems
Хотын усан хангамж	Даралтын үнэлгээ, longevity, аюулгүй байдал	SDR11 (PN16) or SDR13.6 (PN12.5)	PE100 material mandatory
Industrial use	Химийн эсэргүүцэл, даралт, температур	SDR11 (PN16) or SDR9 (PN20)	Verify chemical compatibility
Mining slurry	Элэгдлийн эсэргүүцэл, хананы зузаан	SDR9 or thicker	HDPE’s abrasion resistance is 4× steel
Gas distribution	Аюулгүй байдал, leak-tightness, дүрэм журам	SDR11 (PN16) minimum	Must comply with local gas codes
Ус зайлуулах & ариутгах татуурга	Зардал, flow capacity, химийн эсэргүүцэл	SDR26 to SDR17	Gravity flow often uses SDR26
Кабелийн хамгаалалт	Уян хатан байдал, зардал	SDR33 or higher	Non-pressure application

Дотоод холбоос：

• For irrigation specifics: HDPE усалгааны хоолой
• For industrial standards: HDPE үйлдвэрийн хоолой

5. Check Fitting and Component Compatibility

Because HDPE is OD-controlled, холбох хэрэгсэл, хавхлагууд, and fusion equipment must match the same OD system. Always verify:

• Холбох хэрэгсэл are rated for the same PN class
• Fusion equipment is calibrated for the specific OD and wall thickness
• Transition fittings are available if connecting to other pipe materials

HDPE Pipes in Cable protection

Common HDPE Pipe Size Selection Mistakes

Алдаа 1: Ignoring Pressure Rating

The most common error is selecting a pipe based on diameter alone without verifying the pressure rating. А 110 mm pipe could be SDR17 (PN10) or SDR11 (PN16)—the OD is the same, but the pressure capacity and wall thickness are completely different.

Алдаа 2: Choosing Diameter Only by Cost

Oversizing a pipe increases material cost but may reduce pumping costs over the system’s lifetime. Undersizing saves money upfront but leads to higher energy costs and potential flow restrictions. Always consider life-cycle cost, not just initial purchase price.

Алдаа 3: Ignoring SDR

SDR determines both pressure rating and internal diameter. Two pipes with the same OD but different SDR values have different IDs and different flow capacities. Always specify both the diameter AND the SDR/PN class.

Алдаа 4: Not Considering Future Expansion

Pipeline systems often need to accommodate future growth. Installing a larger diameter or higher pressure class pipe now can save significant costs later. Эргэлзээтэй үед, plan for at least 10–20 years of expected demand growth.

Алдаа 5: Overlooking Temperature Derating

Many engineers specify pipes based on the standard 20°C pressure rating without accounting for higher operating temperatures. In hot climates or systems with elevated temperatures, the effective pressure rating can be significantly lower than the nominal PN class.

Дотоод холбоос：

• For a comprehensive checklist, унших HDPE хоолойн сонголтын алдаа: 7 Инженерүүд худалдан авахаасаа өмнө шалгах ёстой хүчин зүйлүүд

HDPE Pipe Sizes FAQs

1. What are the most common HDPE pipe sizes?

The most commonly used HDPE pipe sizes are 20 мм, 32 мм, 50 мм, 63 мм, 90 мм, 110 мм, 160 мм, 200 мм, 250 мм, 315 мм, болон 400 мм. These cover the majority of water supply, усалгаа, болон үйлдвэрлэлийн хэрэглээ.

2. How do I calculate HDPE pipe diameter?

HDPE pipe diameter is specified by its outside diameter (OF). The inside diameter (ID) depends on the wall thickness, which is determined by the SDR:

ID = OD – (2 × Wall Thickness)

Жишээ нь, а 110 mm OD pipe with SDR11 has a wall thickness of 10.0 мм, so the ID = 110 – (2 × 10.0) = 90 мм.

3. What is the difference between SDR11 and SDR17 HDPE pipe?

SDR11 has a thicker wall than SDR17 for the same outside diameter. For PE100:

• SDR11 = PN16 (16 баар / 1.6 МПа)—higher pressure capacity, smaller internal bore
• SDR17 = PN10 (10 баар / 1.0 МПа)—lower pressure capacity, larger internal bore

Choose SDR11 for high-pressure applications and SDR17 for standard-pressure applications where maximum flow is needed.

4. Does a larger HDPE pipe diameter mean higher pressure?

Үгүй. Pressure rating depends on wall thickness and SDR, not diameter. A small-diameter pipe with a thick wall (бага SDR) can have a higher pressure rating than a large-diameter pipe with a thin wall (high SDR). Always check the SDR or PN class, not just the diameter.

5. What does PN mean in HDPE pipes?

PN гэдэг нь товчлол юм “Нэрлэсэн даралт” and is measured in bars. It indicates the maximum allowable operating pressure at 20°C. Common PN classes include PN6, PN8, PN10, PN12.5, PN16, PN20, болон PN25.

6. HDPE хоолойнууд хэр удаан үргэлжлэх вэ?

HDPE pipes are designed for a service life of50 руу 100 жил with minimal maintenance, provided they are properly selected and installed.

HDPE хоолой

Дүгнэлт

Selecting the right HDPE pipe sizes болон HDPE pipe dimensions is a multi-dimensional engineering decision that goes far beyond simply picking a diameter. A successful selection requires balancing diameter (for flow), хананы зузаан (for pressure via SDR), даралтын үнэлгээ (PN class), болон application-specific requirements such as chemical resistance, abrasion resistance, and installation conditions. By following the four-step method — determining flow rate, checking operating pressure, considering installation conditions, and matching the application — you can avoid common pitfalls and ensure your HDPE piping system delivers reliable performance for its 50+ жилийн дизайны ашиглалтын хугацаа. Whether your project involves municipal water supply, газар тариалангийн усжуулалт, industrial processing, or mining operations, understanding the relationship between HDPE pipe diameter, SDR, болон даралтын үнэлгээ is the key to making informed, cost-effective decisions.

Холбоо барих Luoyang Datang Energy Tech Co., Ltd for customized HDPE pipe solutions tailored to your specific project requirements. Our engineering team is ready to assist with size selection, pressure calculations, and material recommendations.