1. Product Core

Graphite packing gland is a specialized pressure-applying component designed specifically for matching graphite packing (flexible graphite packing, reinforced graphite packing, etc.). Its core function is to convert bolt pre-tightening force into uniform pressure, compressing the graphite packing to fill the gap between equipment moving parts (e.g., shafts) and stuffing boxes-thereby forming a reliable, low-friction sealing interface. This interface effectively prevents leakage of media (liquids, gases, steam) while accommodating slight axial/radial displacement of rotating parts.

Its core values are reflected in:

Addressing common pain points in traditional packing sealing systems, such as uneven packing compression and seal failure caused by pressure relaxation;

Compatibility with various types and specifications of graphite packing (e.g., pure graphite packing, Inconel-reinforced graphite packing), suitable for diverse industrial equipment interfaces (pumps, valves, reactors);

Extending the service life of graphite packing by maintaining stable, continuous preload, and reducing costs associated with frequent replacements.

2. Technical Parameters

Referring to industry standards (API 682, ISO 3704) and extensive user-customized parameter data, the technical specifications are as follows:

Parameter Category	Specification/Range
Material Options	304 stainless steel, 316/316L stainless steel, Hastelloy C-276, carbon steel (Q235B, galvanized)
Size Range	Inner diameter (ID): Φ5mm~Φ200mm; Outer diameter (OD): Φ15mm~Φ280mm; Thickness: 8mm~50mm (special sizes customizable)
Applicable Temperature	-200℃~600℃ (air/oxidizing atmosphere); -200℃~800℃ (inert atmosphere, e.g., nitrogen/argon)
Applicable Pressure	≤ 40MPa (static pressure); ≤ 35MPa (dynamic pressure, applicable to rotating shafts)
Suitable Packing Size	Φ5mm~Φ50mm (circular, square, or rectangular cross-section packing)
Surface Roughness	Inner bore: Ra ≤ 1.6 μm; Outer surface: Ra ≤ 3.2 μm
Bolt Hole Configuration	Number of holes: 4-16 (evenly distributed); Aperture: M6~M30 (metric) / 1/4"~1" (imperial)
Maximum Linear Velocity	≤ 20m/s (applicable to rotating shafts, requiring high-speed graphite packing)
Corrosion Resistance	304/316 stainless steel: Passed 500-hour salt spray test; Hastelloy C-276: No significant corrosion in 10% hydrochloric acid solution

3. Core Features

Based on big data analysis of industrial sealing requirements (covering high corrosion resistance, ease of maintenance, wide working condition adaptability, etc.), graphite packing glands have the following key characteristics:

(1). Durable & Corrosion-Resistant Material Selection

Adopting industrial mainstream metals with high mechanical strength and corrosion resistance:

304/316 stainless steel: Suitable for general corrosive media (e.g., oils, weak acids);

Hastelloy C-276: Suitable for highly corrosive media (e.g., sulfuric acid, chlorine gas);

Coated carbon steel: Cost-effective, suitable for non-corrosive environments.

These materials resist oxidation, chemical erosion, and thermal deformation, ensuring long-term reliable operation in harsh environments.

(2). Structural Design for Optimized Sealing Efficiency

Two mainstream structures:

Integral type: Suitable for small-diameter shafts/valves; easy to install, with low leakage risk;

Split type: Suitable for large-diameter equipment or on-site maintenance; no need to disassemble the shaft, reducing downtime by over 40%;

Precision-machined inner bores: Surface roughness Ra ≤ 1.6 μm, fitting tightly with shafts/valve stems to avoid "side leakage" caused by excessive gaps;

Evenly distributed bolt holes: Ensuring balanced applied pre-tightening force, preventing local overpressure or underpressure of graphite packing.

(3). Wide Working Condition Adaptability

Matching the performance of graphite packing to withstand extreme working conditions:

Temperature range: -200℃~600℃ (air/oxidizing atmosphere); up to 800℃ under inert atmosphere when paired with high-temperature packing;

Pressure range: ≤ 40MPa (static pressure), suitable for high-pressure pumps and reactors in petrochemical and nuclear power fields;

Media compatibility: Compatible with most industrial media, including oils, solvents, acids/alkalis (pH 2-14), high-temperature steam, and inert gases.

(4). Easy Maintenance & Low Operating Costs

Adjustable pre-tightening force: Bolts can be retightened during operation to compensate for packing wear, extending seal life by 2-3 times compared to fixed glands;

Lightweight design: 30% lighter than cast iron glands of the same specification, facilitating on-site handling and installation;

No specialized tools required: Disassembly and assembly can be completed with a regular wrench, reducing labor costs.

4. Typical Applications

Based on global sales data and user feedback analysis, graphite packing glands are widely used in dynamic sealing scenarios for rotating/linear motion equipment across key industries:

Industry Sector	Target Equipment	Specific Application Scenarios
Petrochemical Industry	Centrifugal pumps, gate valves	Shaft seals for crude oil transfer pumps; Valve stem sealing for acid-base reactor discharge valves (media: crude oil, hydrochloric acid, ethylene glycol)
Power Energy	Steam turbines, feedwater pumps	Shaft seals for condensate pumps in thermal power units; Valve packing sealing for nuclear power auxiliary systems (media: high-temperature steam, demineralized water)
Pharmaceutical Industry	Sanitary-grade centrifuges, mixing tanks	Shaft seals for sterile drug mixing tanks; Packing seals for oral liquid transfer pumps (compliant with FDA 21 CFR Part 177.2600 standard, no impurity precipitation)
Metallurgical Industry	Slurry pumps, blast furnace valves	Shaft seals for steel mill slurry pumps; Valve stem sealing for blast furnace hot air valves (media: high-temperature slag slurry, hot air)
Food & Beverage	Homogenizers, juice pumps	Shaft seals for dairy homogenizers; Packing seals for juice transfer pumps (material: 316L stainless steel, rust-proof and easy to clean)