EagleBurgmann H7N Pusher Mechanical Seal

Name: EagleBurgmann H7N Pusher Mechanical Seal – Datasheet & Quote
Brand: EagleBurgmann
SKU: H7N

A balanced pusher seal for stepped shafts, hot water and light hydrocarbons

The EagleBurgmann H7N is a single, balanced, rotating pusher-type mechanical seal for stepped shafts, built to the EN 12756 envelope with a Super-Sinus spring or multiple springs. EagleBurgmann positions it for universal use across pumps: hot water, light hydrocarbons and process media in oil and gas, refining, petrochemical, chemical, power plant, pulp and paper and food and beverage industries. It is independent of the direction of rotation and has a self-cleaning effect, and the seal faces are easily interchangeable, which the manufacturer notes simplifies stock keeping.

The operating range printed in the datasheet covers shaft diameters d1 of 14 to 100 mm with a single spring (multi-spring variants go to 200 mm), pressure to 80 bar for diameters up to 100 mm, and temperatures from -50 C to 220 C.

Technical specifications

Parameter	Specification
Seal type	Single, balanced, rotating pusher seal; Super-Sinus spring or multiple springs; independent of direction of rotation
Shaft diameter d1	14 to 100 mm (0.55 to 3.94 in) for the single spring; variants up to 200 mm
Pressure p1	80 bar (1,160 PSI) for d1 = 14 to 100 mm; 25 bar (363 PSI) for d1 = 100 to 200 mm; 16 bar (232 PSI) for d1 above 200 mm
Temperature	-50 C to 220 C (-58 F to 428 F)
Sliding velocity	20 m/s (66 ft/s)
Axial movement	d1 up to 22 mm: +/-1.0 mm; d1 24 to 58 mm: +/-1.5 mm; d1 from 60 mm: +/-2.0 mm
Seal face materials	Silicon carbide (Q1, Q2); carbon graphite antimony impregnated (A); aluminium oxide (V); CrMo cast steel (S)
Seat (G9) materials	Carbon graphite antimony impregnated (A); carbon graphite resin impregnated (B); silicon carbide (Q1, Q2), not combinable with seal face S
Secondary seals	EPDM (E), NBR (P), FKM (V), FFKM (K)
Springs	CrNiMo steel (G)
Metal parts	CrNiMo steel (G); duplex (G1)
Standard	EN 12756
Torque transmission	Set screws; d1 above 100 mm with four cone-point set screws; drive key version H7S2 / H75S2

Variants, seat options and how to specify

Variant	Shaft diameter	Difference from the H7N
H75	28 to 200 mm	As H7N with multiple springs in sleeves; axial movement +/-2 to 4 mm
H7F	Up to 100 mm	As H7N with a single spring and pumping screw; direction-dependent; viscosity up to ISO VG10
H75F	28 to 200 mm	Multiple springs in sleeves with pumping screw; direction-dependent; viscosity up to ISO VG10
H76	14 to 100 mm	Special single spring that compensates large axial movements of +/-4 mm
H75G115	As H75	Cooled seat, especially for hot water applications

The standard seat G9 follows EN 12756. A G16 seat gives a short installation length, with shorter installed length l1k and l2 than the standard, and G115 is the cooled seat for hot water. To order, state the shaft diameter, the face, seat, secondary seal and spring or metal-part codes, as in the material letters above, and the operating conditions. The datasheet dimension tables list every shaft diameter from 14 mm upward.

Selection and installation notes

Use the H7N where the shaft is stepped and a standard EN 12756 seal envelope is required, and choose the face and seat pairing by the liquid: silicon carbide against silicon carbide for abrasive or poorly lubricating liquids, and carbon against silicon carbide or aluminium oxide for clean hot water and light hydrocarbons. Check the secondary seal material against the liquid and the temperature limit, since the elastomer often limits the seal before the faces do. EagleBurgmann notes that its technical data are guide values based on extensive tests and that the exact application conditions must be notified before any guarantee for a specific case can be given.

For a different pusher seal philosophy see the John Crane Type 2100 elastomer bellows seal, or browse the pumps category.

Documents and quotation

The EagleBurgmann H7N product data sheet (7 pages, EN) lists the operating range, materials, variants, seat options and the dimension tables by shaft diameter is attached to this page and is the manufacturer’s own document, not a Seven Star summary.

Before ordering confirm the shaft diameter and shaft step, pump make and model, liquid, temperature, pressure, speed and the required face and elastomer codes. Seven Star LLC, an independent supplier in Muscat, quotes the EagleBurgmann H7N against your duty point and delivery requirement; send the document tag, flow, head and liquid so the right size can be confirmed before an offer is issued.

EagleBurgmann mechanical seals for pumps

The pump seal catalogue is arranged by design: pusher seals such as the H7N, elastomer bellows seals, metal bellows seals, standard cartridge seals including the Cartex family, split seals, gas-lubricated seals and engineered seals for demanding process duties. The company also lists an API 682 4th edition product range. The manufacturer names oil and gas, refining, petrochemical, chemical, power plant, water and mining among the industries it serves.

Frequently Asked Questions