H1: XZP-550 DC Suspension Insulator (U550B) — 550kN, 700mm Creepage, 400mm Diameter, 32R Coupling, Absolute Ultimate Strength, Zinc Sleeve Protection, Brown/Light Gray Glaze, IEC 60383

The XZP-550 DC Suspension Insulator (U550B) is the absolute ultimate flagship cap‑and‑pin disc insulator in our entire product portfolio, engineered for the most extreme ultra‑high‑voltage direct current (UHVDC) overhead transmission lines. With the highest mechanical rating ever offered — 550kN — the longest creepage distance of 700mm, and the largest 400mm diameter with 32R coupling, this insulator represents the pinnacle of porcelain insulator engineering for ±1100 kV UHVDC applications.

 

Manufactured in compliance with IEC 60383 international standards, this DC insulator features a robust porcelain body with superior characteristics to resist DC ageing. The pins are equipped with zinc sleeves to prevent DC electrolytic corrosion, ensuring long‑term reliability in the most demanding UHVDC applications. The unit is available in either brown (standard) or light gray (optional) glaze, both offering identical mechanical and electrical performance.

 

With a combined mechanical and electrical (M&E) failing load of 550kN — the absolute highest in the entire product portfolio — an industry‑leading creepage distance of 700mm, and a massive 400mm diameter, the XZP-550 delivers unparalleled performance on ±1100 kV and above UHVDC transmission lines in the most extreme environments. The 400mm diameter, industry‑leading 240mm spacing, and advanced shed design provide the greatest surface area for maximum pollution flashover performance and mechanical stability.

 

The advanced DC‑optimized shed design incorporates a specialized profile that maximizes the industry‑leading 700mm creepage length while maintaining superior self‑cleaning properties. The porcelain material’s superior DC ageing resistance, combined with zinc sleeve protection against electrolytic corrosion and the heavy‑duty 32R coupling, ensures decades of reliable service in the most extreme UHVDC applications.

 

Whether you are designing ±1100 kV and above UHVDC transmission corridors, critical national grid backbone infrastructure, or the most demanding ultra‑long‑span river crossings requiring absolute ultimate strength and performance, the XZP-550 DC suspension insulator offers the absolute ultimate flagship choice for your HVDC infrastructure, with the flexibility to select your preferred glaze color.

 

H2: XZP-550 DC Suspension Insulator — Technical Specifications (Brown & Light Gray Glaze)

The XZP-550 DC suspension insulator is rated with a combined mechanical and electrical (M&E) failing load of 550kN — the absolute highest in the entire product portfolio — making it suitable for tangent suspension, light‑tension, strain, and dead‑end applications on ±1100 kV and above UHVDC transmission lines where ultimate mechanical strength is required.

 

Its industry‑leading creepage distance of 700mm — 155mm longer than standard 545mm DC designs and 50mm longer than the 650mm of the XZSP1-420 — provides superior pollution flashover performance in the most severe industrial, coastal, and desert environments. The DC dry withstand voltage reaches 150kV — 10kV higher than standard DC models — and the DC wet withstand voltage is 60kV — 5kV higher than standard models. The dry lightning impulse withstand voltage is 150kV (positive) and 160kV (negative).

 

The nominal diameter is 400mm — the largest in the entire DC portfolio — with a unit spacing (height) of 240mm — the tallest in the series. These maximum‑in‑series dimensions provide the greatest surface area for improved pollution performance, enhanced self‑cleaning, and superior mechanical stability under the highest mechanical loads.

 

The coupling hardware is the largest 32R ball‑and‑socket type, ensuring full interchangeability with existing heavy‑duty UHVDC fittings per IEC dimensional requirements. The “R” designation indicates the heavy‑duty rotary coupling design, accommodating the absolute highest mechanical loads associated with the 550kN rating.

 

The pins are equipped with zinc sleeves to prevent DC electrolytic corrosion — a critical feature for UHVDC applications where standard galvanized pins would degrade due to unidirectional current flow.

 

The Figure 1 advanced shed design provides optimized DC pollution performance for the most severe contamination environments.

 

The glaze is available in both brown (standard) and light gray (optional). All other technical parameters — mechanical, electrical, and dimensional — are identical between the two color options.

 

Every unit undergoes a routine tension load test of 275kN — the highest in the entire DC series — to verify mechanical integrity prior to dispatch. The SF₆ puncture withstand voltage reaches 225kV — 15kV higher than standard models — demonstrating exceptional dielectric robustness. The impact load is rated at 10N·m.

 

H2: XZP-550 DC Suspension Insulator — Complete Technical Data (Brown vs. Light Gray Glaze)

The following table lists all technical parameters for both glaze color options. All values are identical except for the glaze color.

Parameter	XZP-550 (Brown Glaze)	XZP-550 (Light Gray Glaze)
Glaze Color	Brown	Light Gray
Type Designation	XZP-550 (U550B)	XZP-550 (U550B)
Figure No.	1	1
Diameter D (mm)	400	400
Unit Spacing H (mm)	240	240
Nominal Creepage Distance L (mm)	700	700
Coupling Size	32R	32R
Rated M&E Failing Load (kN)	550	550
Routine Tension Load (kN)	275	275
Impact Load (N·m)	10	10
DC Dry Withstand Voltage (kV)	150	150
DC Wet Withstand Voltage (kV)	60	60
Dry Lightning Impulse Withstand (Positive) (kV)	150	150
Dry Lightning Impulse Withstand (Negative) (kV)	160	160
SF₆ Puncture Withstand Voltage (kV)	225	225
Net Weight, Approximate (kg)	30.3	30.3
Applied Standard	IEC 60383	IEC 60383

 

Note: The XZP-550 DC suspension insulator is the absolute ultimate flagship model in our entire product portfolio, combining the highest 550kN mechanical rating with the industry‑leading 700mm creepage distance, the largest 400mm diameter, the tallest 240mm spacing, the largest 32R coupling, and the highest electrical ratings (150kV DC dry, 60kV DC wet, 225kV SF₆ puncture) — delivering absolute ultimate mechanical strength, superior flashover performance, and maximum surface area for the most demanding ±1100 kV and above UHVDC applications. Both brown and light gray glazes offer the same outstanding performance.

 

H2: XZP-550 DC Suspension Insulator — DC‑Specific Design Features

The XZP-550 DC suspension insulator incorporates the most advanced design features ever developed for ultra‑demanding UHVDC transmission applications, setting the absolute benchmark for porcelain insulator engineering:

 

• Zinc sleeve protection — The pins are equipped with zinc sleeves that prevent DC electrolytic corrosion. In UHVDC applications, unidirectional current flow can cause accelerated corrosion of standard galvanized components. The zinc sleeves act as a sacrificial anode, protecting the critical pin components and ensuring long‑term mechanical integrity even at the highest 550kN loads.
• DC‑optimized porcelain material — The high‑grade porcelain body is formulated with superior characteristics to resist DC ageing. Unlike AC insulators, DC insulators are subject to continuous unidirectional voltage stress that can accelerate dielectric ageing. Our special porcelain formulation maintains consistent dielectric strength throughout the insulator’s service life.
• Advanced Figure 1 shed profile — The advanced DC‑optimized shed geometry is specifically designed to maximise the industry‑leading 700mm creepage distance while maintaining effective self‑cleaning properties. The optimized profile enhances pollution flashover performance in heavy contamination areas where DC insulators are particularly vulnerable.
• Largest physical dimensions — The 400mm diameter and 240mm spacing — the largest in the entire product portfolio — provide the greatest surface area for maximum pollution performance and mechanical stability under the most extreme conditions.
• Heavy‑duty 32R coupling — The largest coupling size in the entire product portfolio, accommodating the absolute highest mechanical loads and ensuring compatibility with the most robust UHVDC hardware.
• Industry‑leading 700mm creepage distance — The longest creepage distance ever offered, providing maximum pollution flashover performance.
• Superior electrical ratings — 150kV DC dry withstand, 60kV DC wet withstand, 225kV SF₆ puncture withstand — all the highest in the DC series.
• IEC 60383 compliance — Full compliance with international standards ensures global interchangeability and quality assurance.

 

Each XZP-550 DC suspension insulator is produced from high‑grade porcelain, fired at over 1,300 °C using the wet process, achieving maximum density and near‑zero porosity. The zinc sleeves are precision‑applied to ensure optimal corrosion protection throughout the insulator’s service life.

 

The cement bonding between the porcelain body and metal parts uses high‑quality Portland cement, guaranteeing mechanical stability across extreme thermal cycling from ‑70 °C to +105 °C.

 

The hard, glossy glaze — available in brown or light gray — further enhances self‑cleaning and maintains surface integrity over decades of service. Both glaze colors are applied using the same high‑quality process, ensuring identical durability, hardness, and electrical performance.

 

H2: XZP-550 DC Suspension Insulator — Applications and Installation

The XZP-550 DC suspension insulator is the absolute ultimate flagship solution for the most demanding ±1100 kV and above UHVDC transmission lines, as well as ultra‑long‑span major river crossings, national grid backbone infrastructure, and the most extreme HVDC applications where ultimate mechanical strength and performance are required.

 

The 550kN mechanical rating — the absolute highest in the entire product portfolio — combined with the industry‑leading 700mm creepage distance, largest 400mm diameter, 240mm spacing, largest 32R coupling, and superior electrical ratings makes it particularly suitable for:

• ±1100 kV and above UHVDC transmission lines – Where the highest reliability and ultimate mechanical strength are required for bulk power transmission over the longest distances.
• National grid backbone infrastructure – Where system reliability and security of supply are paramount, and maximum mechanical and pollution margins are required.
• Ultra‑long‑span major river crossings – Where conductor weight and tension are at their absolute maximum, requiring the highest possible mechanical rating.
• Extreme heavy icing zones – Where ice accretion adds extreme weight and mechanical stress, requiring the highest mechanical rating in the DC series.
• Heavy pollution areas with extreme conditions – Industrial zones, coastal regions, and desert environments where maximum surface area and pollution performance are essential.
• UHVDC converter stations – Heavy‑duty strain and dead‑end towers at UHVDC converter station entries where flagship DC insulators are required.
• Critical international interconnections – Cross‑border UHVDC links requiring the highest performance insulators.
• Seismic zones – Where maximum mechanical robustness is required for earthquake‑prone regions.
• Ultra‑high‑tension dead‑end towers – Where absolute ultimate mechanical strength is non‑negotiable.

 

The 32R coupling with zinc sleeves ensures compatibility with existing heavy‑duty UHVDC hardware and provides maximum protection against electrolytic corrosion. The DC‑optimized Figure 1 shed design facilitates hot‑stick handling for live‑line maintenance.

 

Typical application scenarios include:

• ±1100 kV UHVDC lines – Flagship strain and dead‑end towers requiring ultimate mechanical strength and largest dimensions.
• ±800 kV UHVDC lines – Ultra‑heavy‑duty applications where only the highest mechanical rating is acceptable.
• Major river crossings – Critical infrastructure requiring the absolute highest mechanical rating and performance.
• National grid backbone – Core transmission corridors where reliability is paramount.

 

The 32R ball‑and‑socket coupling ensures compatibility with existing heavy‑duty UHVDC clevis pins, yokes, and socket hardware. The DC‑specific design features — zinc sleeves, DC‑optimized Figure 1 shed profile, and special porcelain formulation — ensure maximum reliability in the most demanding UHVDC applications.

 

For higher voltage requirements, multiple units of the XZP-550 DC suspension insulator can be assembled in strings. Explore our full range of suspension insulators and transmission hardware for more options.

 

H2: XZP-550 DC Suspension Insulator — Quality and Performance Advantages

The XZP-550 DC suspension insulator represents the absolute ultimate flagship pinnacle of mechanical strength, creepage distance, physical dimensions, and DC‑specific protection in our entire product portfolio — the ultimate engineering achievement for the most extreme UHVDC applications.

 

Key performance advantages include:

• 550kN mechanical rating – The absolute highest in the entire product portfolio, providing 390kN (244%) more strength than the XZP-160, 340kN (162%) more than the XZP-210, 250kN (83%) more than the XZWP-300, and 130kN (31%) more than the XZSP1-420.
• 700mm creepage distance – The longest in the entire product portfolio, 155mm (+28%) longer than standard 545mm DC designs and 50mm (+8%) longer than the 650mm of the XZSP1-420.
• 400mm diameter – The largest diameter in the entire product portfolio, providing the greatest surface area for maximum pollution performance and self‑cleaning.
• 240mm spacing – The tallest spacing in the entire product portfolio, providing enhanced mechanical stability and maximum surface area.
• 32R coupling – The largest coupling size in the entire product portfolio, accommodating the highest mechanical loads.
• 150kV DC dry withstand voltage – The highest in the DC series, 10kV higher than standard models.
• 60kV DC wet withstand voltage – The highest in the DC series, 5kV higher than standard models.
• 225kV SF₆ puncture withstand voltage – The highest in the DC series, 15kV higher than standard models.
• DC‑optimized porcelain formulation – Superior resistance to DC ageing, ensuring decades of reliable dielectric performance.
• Zinc sleeve protection – Prevents DC electrolytic corrosion, extending mechanical service life significantly.
• 275kN routine tension load – The highest routine tension test load in the entire product portfolio.
• IEC 60383 compliance – Manufactured to international standards for global quality assurance.

 

At 30.3kg, the XZP-550 offers an exceptional strength‑to‑weight ratio for a 550kN flagship DC insulator — only 14.0kg heavier than the XZSP1-420 (16.3kg) while delivering a 130kN (31%) higher mechanical rating, a 50mm longer creepage distance, a 35mm taller spacing, and significantly higher electrical ratings.

 

With an expected service life exceeding 50 years under normal UHVDC operating conditions, the XZP-550 requires minimal routine maintenance. Every unit undergoes 100% routine testing before dispatch, including:

• Visual and dimensional inspections.
• Routine tension load verification (275 kN).
• DC dry and wet withstand voltage tests.
• Porosity and temperature‑cycle prototype testing per IEC 60383.

 

Each insulator is individually foam‑cushioned and securely packed in durable wooden crates or corrugated cartons. This prevents damage during transit. We offer flexible shipping arrangements (FOB, CIF, EXW) with lead times of 15–30 days, depending on order quantity.

 

For detailed product datasheets, CAD drawings, or competitive pricing on the XZP-550 DC suspension insulator (brown or light gray), please contact our sales team via the inquiry form below.

 

We also provide OEM services and complimentary technical consultation for UHVDC string assembly design. For installation guidance, refer to our insulator string assembly guide.

 

H2: XZP-550 DC Suspension Insulator — Why Choose Our Product?

Selecting the right DC suspension insulator for your HVDC infrastructure is critical to long‑term grid reliability — especially in ±1100 kV and above UHVDC projects where absolute ultimate mechanical strength, the longest creepage distance, and the largest physical dimensions are required. Our XZP-550 DC suspension insulator is manufactured under stringent quality control protocols at every production stage.

 

From raw material sourcing (DC‑optimized high‑grade porcelain clay) to final high‑voltage DC testing, every step aligns with IEC 60383. We understand that the most demanding UHVDC transmission projects — ±1100 kV and above corridors, ultra‑long‑span river crossings, and national grid backbone infrastructure — require the absolute highest levels of mechanical strength, creepage distance, and pollution performance that even 420kN DC insulators cannot provide.

 

That is why the XZP-550 DC suspension insulator is specifically engineered with a 550kN mechanical rating — the absolute highest in our entire product portfolio — combined with an industry‑leading 700mm creepage distance, the largest 400mm diameter, the tallest 240mm spacing, the largest 32R coupling, advanced Figure 1 shed design, the highest 150kV DC dry withstand, 60kV DC wet withstand, and 225kV SF₆ puncture withstand ratings, zinc sleeve protection against DC electrolytic corrosion, and DC‑optimized porcelain with superior resistance to DC ageing to deliver absolute ultimate flagship performance in the most demanding UHVDC applications. Additionally, we offer both brown and light gray glaze options to match regional preferences or project specifications.

 

With over a decade of experience in porcelain insulator production — including specialized DC and UHVDC insulator manufacturing — we offer competitive factory pricing, prompt delivery, and dedicated after‑sales technical support.

 

Whether you require a small sample batch for project validation or a full container shipment, the XZP-550 DC suspension insulator (brown or light gray) is available with short lead times. Contact us today to discover how the XZP-550 DC suspension insulator can strengthen your UHVDC grid reliability with its absolute ultimate flagship combination of highest mechanical strength, longest creepage distance, and largest dimensions.

 

XZP-550 — Key Specifications

Parameter	XZP-550 (U550B)
M&E Failing Load	550 kN
Routine Tension Load	275 kN
Impact Load	10 N·m
Nominal Diameter D	400 mm
Unit Spacing H	240 mm
Creepage Distance L	700 mm
Coupling Size	32R
Figure No.	1
DC Dry Withstand Voltage	150 kV
DC Wet Withstand Voltage	60 kV
Lightning Impulse (+/-)	150 / 160 kV
SF₆ Puncture Withstand	225 kV
Zinc Sleeve Protection	✓
DC Ageing Resistance	✓
Net Weight	30.3 kg
Glaze Options	Brown / Light Gray
Best Application	±1100kV and above UHVDC (absolute ultimate flagship)

 

XZP / XZWP / XZSP1 / XZP DC Series — Complete Comparison

Parameter	XZP-160 (U160BL)	XZP-210 (U210B)	XZWP-300 (U300B)	XZSP1-420 (U420B)	XZP-550 (U550B)
M&E Failing Load	160 kN	210 kN	300 kN	420 kN	550 kN
Routine Tension Load	80 kN	105 kN	150 kN	210 kN	275 kN
Impact Load	10 N·m	10 N·m	—	—	10 N·m
Diameter D	320 mm	320 mm	360 mm	400 mm	400 mm
Unit Spacing H	170 mm	170 mm	195 mm	205 mm	240 mm
Creepage Distance L	545 mm	545 mm	545 mm	650 mm	700 mm
Coupling Size	20R	20R	24R	28R	32R
Figure No.	1	1	2	3	1
DC Dry Withstand	140 kV	140 kV	140 kV	140 kV	150 kV
DC Wet Withstand	55 kV	55 kV	55 kV	55 kV	60 kV
Lightning Impulse (+/-)	140/150 kV	140/150 kV	140/150 kV	140/150 kV	150/160 kV
SF₆ Puncture	210 kV	210 kV	210 kV	210 kV	225 kV
Zinc Sleeve	✓	✓	✓	✓	✓
DC Ageing Resistance	✓	✓	✓	✓	✓
Net Weight	13.2 kg	13.6 kg	16.3 kg	16.3 kg	30.3 kg
Relative Strength	Baseline	+31%	+88%	+163%	+244%
Key Advantage	Standard DC	Higher strength	Flagship strength	Ultimate flagship	Absolute ultimate flagship
Best Application	±400-800kV	±400-800kV	±400-800kV	±800-1100kV	±1100kV and above UHVDC