HDPE pipe and fitting,PVC pipe and fitting

High-density polyethylene (HDPE) pipe is widely used in underground cable protection projects due to its excellent corrosion resistance, impact resistance, flexibility and long life. HDPE cable protection pipe can effectively prevent the cable from mechanical damage, chemical corrosion and groundwater infiltration, and is convenient for later maintenance and expansion. This article will comprehensively analyze the price of HDPE pipe for underground cable protection from the aspects of price influencing factors, market conditions, and purchase recommendations.

 

Main factors affecting the price of HDPE cable protection pipe

(1) Raw material cost

The main raw material of HDPE pipe is high-density polyethylene resin, and its price is greatly affected by fluctuations in the international crude oil market.

Adding modified materials such as UV resistance and flame retardants will increase the cost.

(2) Pipe specifications

Pipe diameter (DN): The larger the pipe diameter, the more material is used and the higher the price (for example, DN110 is 30%-50% more expensive than DN50).

Wall thickness (SDR value): SDR11 (thick wall) is 20%-40% more expensive than SDR17 (thin wall).

Ring stiffness (SN value): SN8 (high stiffness, suitable for deep burial) is 10%-30% more expensive than SN4 (ordinary stiffness).

(3) Production process

Ordinary single-wall pipe: lower price, suitable for general burial environment.

MPP (modified polypropylene) pipe: better high temperature resistance, but the price is 30%-50% higher than HDPE pipe.

(4) Quality certification

Pipes certified by ISO 9001, CE, ROHS, etc. are usually 10%-20% higher than ordinary products.

(5) Purchase volume and transportation cost

Bulk purchase (such as more than 1,000 meters): a certain discount can be enjoyed.

Transportation distance: Long-distance transportation will increase logistics costs, especially for large-diameter pipes.

 

How to reduce procurement costs?

Choose specifications as needed: SDR17 or SN4 can be selected for non-heavy load environments to reduce costs.

Bulk purchase: A one-time purchase of more than 1,000 meters can get a bigger discount.

 

Purchase suggestions

Communication optical cable protection: Single-wall pipe (SDR11) can meet the needs.

High temperature environment (such as power plants): It is recommended to use MPP pipe, which can withstand temperatures above 90°C.

Corrosive soil: Choose HDPE pipe with anti-corrosion agent added to extend service life.

 

The price of HDPE pipe for underground cable protection is affected by multiple factors such as specifications, materials, brands, and purchase volume. Reasonable selection, bulk purchases, and attention to market trends can effectively control costs. It is recommended to give priority to quality certification and applicable scenarios when purchasing, rather than simply pursuing low prices, to ensure the long-term reliability of the project.

Official website: www.phtopindustry.com | www.pefitting.net
Contact us: Email:inquiry@phtopindustry.com | Whatsapp:+86 15093100892
Company address: Room 802, 8th Floor, Building 5, Jinyin Modern City, Jinshui District, Zhengzhou City, Henan Province, China

 

High-density polyethylene (HDPE) pipes have become one of the preferred materials for industrial wastewater treatment systems due to their excellent performance. The main advantages include:

Excellent corrosion resistance: Can withstand various acids, alkalis, salts and organic solvents, suitable for treating industrial wastewater with complex components

Excellent impact resistance: Not easy to crack even in low temperature environments

Good flexibility: Can adapt to a certain degree of foundation settlement

Long service life: Design service life can reach more than 50 years

Smooth inner wall: Small friction coefficient, strong conveying capacity and not easy to scale

Reliable connection: Hot-melt connection forms an integral structure without leakage risk

Environmental protection and safety: The material is non-toxic and does not pollute water quality

 

Specifications of commonly used HDPE pipes for industrial wastewater treatment

1. Pipe diameter specifications

The diameter range of commonly used HDPE pipes in industrial wastewater treatment systems:

Small diameter pipes: DN20-DN200 (used for dosing systems, sampling lines, etc.)

Medium diameter pipes: DN250-DN600 (mainstream process pipelines)

Large diameter pipes: DN600-DN2000 (used for plant main pipelines, discharge pipelines, etc.)

Ultra-large diameter: DN2000 and above (special engineering applications)

2. Pressure level

Select pipes of different pressure levels according to the system working pressure:

PN0.6MPa: low pressure system, such as gravity flow pipelines

PN0.8MPa: general pressure system

PN1.0MPa: medium pressure system

PN1.25MPa: higher pressure system

PN1.6MPa: high pressure system, such as pumping pipelines

3. Wall thickness standard

HDPE pipe wall thickness is usually divided into SDR (standard dimension ratio) series:

SDR11: thick wall pipe, strong pressure bearing capacity

SDR17: medium wall thickness, balanced economy and strength

SDR26: thin wall pipe, used in low pressure system

Specific wall thickness can refer to GB/T 13663.2-2018 standard.

4. Material grade

HDPE pipe produced from PE100 grade raw materials is recommended for industrial wastewater treatment, which has higher long-term hydrostatic strength and crack growth resistance.

 

Specifications of HDPE pipes for special purposes

1. Chemical corrosion resistant pipes

For industrial wastewater containing highly corrosive components, the following should be considered:

Select PE100 RC (stress cracking resistance) material

Increase the wall thickness design margin (reduce the SDR value by one level)

Consider a special anti-corrosion layer for the inner lining (such as PP lining)

2. High-temperature wastewater pipes

When the wastewater temperature exceeds 40°C:

Select high-temperature resistant HDPE material (such as PE-RT)

The pressure level needs to be increased by one level

Consider thermal expansion compensation design

3. Underground buried pipes

Ring stiffness selection: SN8 or above (SN12.5 or above for heavy-load areas)

Consider the outer anti-corrosion layer (such as double-wall corrugated pipe structure)

The relationship between burial depth and load needs to be calculated.

 

Selection of HDPE pipe connection methods

Select the appropriate connection method according to the pipe diameter and engineering requirements:

Hot-melt butt: suitable for DN≥90mm pipes, high connection strength

Electrofusion connection: suitable for various pipe diameters, easy to install

Flange connection: required to connect with metal equipment

Socket connection: commonly used for small-diameter pipes

 

Selection considerations

1. Water quality characteristics analysis: understand wastewater pH value, chemical composition, temperature and other parameters

2. Hydraulic calculation: determine pipe diameter and pressure loss

3. Environmental factors: consider burial conditions, ambient temperature, earthquake level, etc.

4. Standard compliance: ensure that the product complies with standards such as GB/T 13663 and ISO 4427

5. Economic evaluation: balance initial investment and long-term operating costs

 

Correctly selecting HDPE pipe specifications is crucial to the long-term stable operation of industrial wastewater treatment systems. Engineering designers should select the most suitable HDPE pipe specifications based on specific wastewater characteristics, process requirements and site conditions, combined with relevant standards and specifications, while considering the convenience of installation and maintenance and the full life cycle cost, to provide reliable transportation guarantees for wastewater treatment systems.

Official website: www.phtopindustry.com | www.pefitting.net
Contact us: Email:inquiry@phtopindustry.com | Whatsapp:+86 15093100892
Company address: Room 802, 8th Floor, Building 5, Jinyin Modern City, Jinshui District, Zhengzhou City, Henan Province, China

 

Core Advantages of HDPE Pipes in Agricultural Irrigation

HDPE (High-Density Polyethylene) pipes have become the preferred choice for modern agricultural irrigation systems due to their outstanding advantages:

Exceptional Weather Resistance: UV-resistant additives ensure over 20 years of outdoor use without aging

Superior Flexibility: Can withstand ground settlement with seismic resistance 5 times that of steel pipes

Ultra-Low Water Delivery Loss: Inner wall smoothness of 0.009mm, with friction coefficient only 1/3 of steel pipes

Eco-Friendly and Safe: NSF certified, fully compliant with drinking water standards

Cost-Effective and Durable: 40% lower overall cost than steel pipes with a service life of 50 years

 

Five Key Indicators for Scientific Selection

(1) Golden Rules for Pipe Diameter Calculation

Flow Rate Formula:
Q=π×(D/2)²×v×3600
(Q: m³/h; D: Pipe diameter in m; v: Flow velocity in m/s)

Flow Velocity Control Standards:

Branch pipes: 0.6-1.0m/s

Main pipes: 1.0-1.5m/s

Maximum not exceeding 2.5m/s

Common Specification Reference Table:

Irrigation Area (acre)	Drip Irrigation System	Sprinkler System	Main Pipeline
Below 50	Φ32-50mm	Φ63-75mm	Φ90-110mm
50-200	Φ50-63mm	Φ75-90mm	Φ110-160mm
200-500	Φ63-75mm	Φ90-110mm	Φ160-200mm

(2) Pressure Rating Selection Guide

Pressure Loss Formula:
hf=λ×(L/D)×(v²/2g)
(λ value: 0.02-0.03)

Pressure Rating Recommendations:

Irrigation Type	Working Pressure	Recommended Rating	Safety Factor
Drip Irrigation	0.15MPa	PN0.8	1.5
Micro Spray	0.25MPa	PN1.0	1.6
Sprinkler	0.5MPa	PN1.6	1.8
Hub Project	0.8MPa	PN2.0	2.0

(3) Advanced Material Selection Guide

PE100 vs PE80:

Strength: PE100 is 25% stronger than PE80

Cost: PE100 is 15-20% more expensive

Application Scenarios:

Drip irrigation branch pipes: PE80

High-pressure main pipes: PE100

Anti-Aging Performance:

Standard type: 3 years outdoor lifespan

UV-resistant type: Contains 2.5% carbon black, lifespan 20+ years

Recommendation: Above-ground sections must use UV-resistant type

 

Solutions for Special Working Conditions

(1) High-Sediment Water

Choose SDR11 thick-walled pipes

Maintain flow velocity above 1.2m/s to prevent sedimentation

Install sediment traps every 500m

(2) Cold Climate Areas

Use low-temperature impact-resistant PE-RT material

Burial depth ≥ frost line +20cm

Implement electric heat tracing systems

(3) Slope Irrigation

Use SDR17 series for slopes >15°

Install pressure relief valves every 50m

Use flange-type anchor blocks for fixation

 

Cost Optimization Strategies

Pipe Diameter Combination Plan:

Main pipes: PE100 PN1.6

Branch pipes: PE80 PN1.0

Capillary pipes: PE40 PN0.6

Procurement Techniques:

Bulk purchase discounts: >5000 meters can get 20% off

Seasonal procurement: 10-15% lower prices in winter

Direct factory purchase eliminates middleman margins

 

Key Quality Control Points for Installation

Hot Melt Welding Parameters:

Temperature: 210±5?

Pressure: 0.15-0.3MPa

Time: Pipe diameter ×10 seconds (mm)

Pressure Testing Standards:

Strength test: 1.5× working pressure, hold for 1 hour

Leak test: 1.1× working pressure, hold for 2 hours

Backfill Requirements:

First layer: 20cm fine sand bedding

Compact in layers (each layer ≤30cm)

Compaction density ≥90%

 

Solutions to Common Problems

Water Hammer Effect:

Install slow-closing check valves

Set up pressure regulating towers

Use SDR26 thin-walled pipes to absorb impact

Algae Growth:

Choose black opaque pipes

Regularly inject sodium hypochlorite solution

Install UV sterilizers

Rodent Damage:

Use HDPE material with rodent repellent

Burial depth ≥80cm

Use protective sleeves for critical sections

Through scientific selection, HDPE irrigation systems can achieve 30% water savings, 25% energy savings, and 15% yield increase. We recommend involving professional irrigation engineers at the planning stage and adopting EPC mode to ensure optimal system performance.

Official website: www.phtopindustry.com | www.pefitting.net
Contact us: Email:inquiry@phtopindustry.com | Whatsapp:+86 15093100892
Company address: Room 802, 8th Floor, Building 5, Jinyin Modern City, Jinshui District, Zhengzhou City, Henan Province, China

HDPE (High-Density Polyethylene) pipes can be connected in various ways depending on engineering requirements, pressure ratings, and construction conditions. Below are the common HDPE pipe connection methods and their characteristics:

1. Heat Fusion

Application: Pressure pipe systems (e.g., water supply, gas pipelines)
Advantages: Strong sealing, high joint strength (close to the pipe material itself)
Disadvantages: Requires specialized equipment and trained operators

Type	Key Steps	Applicable Pipe Sizes
Butt Fusion	Heats pipe ends to a molten state, then presses them together (requires trimming, temperature control at 200-220°C)	DN20-DN1200
Electrofusion	Uses fittings with built-in heating wires (automated temperature control, suitable for confined spaces)	DN20-DN400
Socket Fusion	Simultaneously heats pipe end and fitting before insertion (common for small-diameter pipes)	DN20-DN110

2. Mechanical Joints

Application: Temporary projects, non-pressure pipelines, or repairs
Advantages: Quick installation, detachable
Disadvantages: Requires periodic sealing inspection

Type	Features
Flange Connection	Bolted flange connection with gasket sealing, suitable for valve/equipment connections
Clamp Coupling	Uses stainless steel clamps to compress rubber seals, ideal for emergency repairs or connecting different materials
Compression Fitting	Seals via threaded compression, typically used for small pipes (DN ≤ 63)

3. Other Connection Methods

Method	Description
Steel-Plastic Transition Fitting	Connects HDPE to metal pipes (internal sealing and anti-pullout structure)
Heat-Shrink Sleeve Connection	Uses a heat-shrink sleeve to seal joints by flame heating (common for cable protection pipes)

 

Selection Recommendations

Pressure pipelines: Prefer heat fusion (Butt Fusion > Electrofusion)

Non-pressure pipelines: Mechanical connections are more economical (e.g., clamp couplings for drainage pipes)

Special environments:

Underground concealed works → Heat fusion

Confined spaces → Electrofusion

Temporary projects → Flange/Clamp connections

 

Important Notes

Clean pipe ends before heat fusion to avoid contamination.

 

Mechanical connections require periodic seal inspection (recommended replacement every 5 years).

Official website: www.phtopindustry.com | www.pefitting.net
Contact us: Email:inquiry@phtopindustry.com | Whatsapp:+86 15093100892
Company address: Room 802, 8th Floor, Building 5, Jinyin Modern City, Jinshui District, Zhengzhou City, Henan Province, China

 

The low temperature resistance of HDPE pipe (high-density polyethylene pipe) is excellent, which is one of the key advantages of its wide application in cold areas. The following is a specific analysis:

 

Low temperature resistance performance

Minimum tolerance temperature:

HDPE pipe can still maintain flexibility and impact resistance in extremely cold environments of -40? to -60?, and will not become brittle and crack.

(Comparison: PVC pipes become brittle below 0?, and steel pipes lose toughness below -20?)

Low temperature impact resistance:

At -40?, the impact strength of HDPE can still reach more than 60% of that at room temperature, which is much higher than other plastic pipes (such as PPR, PVC).

Anti-frost expansion ability:

Due to the flexibility of HDPE, the pipe can withstand the volume expansion (about 9%) when the internal water freezes, reducing the risk of freezing and cracking.

Core advantages (compared with other pipes)

Performance Indicator	HDPE Pipe	PVC Pipe	Steel Pipe
Minimum Service Temperature	-40? to -60?	0? to 5?	-20? to -30?
Low-Temperature Brittleness	None	Highly Prone to Cracking	Reduced Toughness
Frost Heave Resistance	Can Buffer Through Deformation	Direct Fracture	Potential Weld Cracking

 

Low temperature resistance principle

Molecular structure characteristics:

The linear molecular chain structure of HDPE can still maintain flexibility at low temperatures and is not prone to glass transition (Tg as low as -120?).

Additive enhancement:

High-quality HDPE pipes will add low temperature modifiers (such as elastomers) to further improve impact resistance in cold environments.

 

Application cases in cold regions

Projects within the Arctic Circle: Alaska oil pipelines use HDPE pipes to withstand extreme climates of -50?.

Rural water supply in northern China: HDPE pipes are promoted in Heilongjiang, Inner Mongolia and other places to solve the problem of traditional pipes freezing and cracking in winter.

Alpine ski field irrigation: HDPE pipes are used as snowmaking system pipes in the Swiss Alps.

 

Precautions for use

Material selection recommendations:

Choose HDPE pipes made of PE100 grade raw materials (more resistant to low temperatures than PE80)

Confirm that the product has passed the ISO 9080 low temperature weathering test

Installation points:

The burial depth should be lower than the local permafrost layer (for example, ≥1.5 meters is recommended in northern China)

Use electric fusion connection (more suitable for low temperature construction than hot fusion)

Maintenance management:

It is recommended to drain the pipe when it is not used in winter

Exposure pipes can be coated with insulation materials (such as PEF foam)

 

HDPE pipe is one of the pipes with the best low temperature resistance at present, and is particularly suitable for water supply and gas transportation in high-cold areas. It has become the preferred solution for infrastructure construction in cold areas with its advantages of anti-frost heave, corrosion resistance and long life.

Official website: www.phtopindustry.com | www.pefitting.net
Contact us: Email:inquiry@phtopindustry.com | Whatsapp:+86 15093100892
Company address: Room 802, 8th Floor, Building 5, Jinyin Modern City, Jinshui District, Zhengzhou City, Henan Province, China