DN100 4 Inch Single Sphere Rubber Expansion Joint FKM High Temperature Flange Compensator

Product Description:

Rubber expansion joints fail for one of two reasons: the wrong compound, or the wrong installation. On hot oil and thermal fluid lines the second problem is rare, but the first is common — an EPDM sphere that performs perfectly on cold water will harden and crack within months when the medium is oil at 120°C.

This DN100 (4 inch) FKM version answers that case. The fluorocarbon sphere handles oil, fuel and solvent service and stays flexible up to 150°C with the special compound, while the flange ends keep the same DIN, ANSI or JIS drilling as the rest of the range so it bolts onto an existing line without adaptors.

Applications:

• Heat transfer oil and thermal fluid circuits
• Boiler feed, condensate and hot water lines near heat sources
• Diesel, lubricant and fuel oil transfer piping
• Chemical dosing and solvent service where EPDM would swell
• Exhaust, engine test bench and hot gas ducting connections
• Pump discharge on high temperature process headers

Product Features:

• FKM sphere for service up to 150°C, where standard EPDM would age out early
• Resists swelling in mineral oil, diesel, lubricant and many solvents
• Same 150mm face length and 4 inch bore as the standard range, so it drops into existing pipe gaps
• Flange ends drilled to DIN, ANSI or JIS, bolted straight to the line
• Cord fabric carcass and galvanized wire ring hold the sphere shape at full pressure
• Other compounds (EPDM, NBR, NR, CR) quoted when the medium calls for them

Technical Parameters:

Advantages:

• Thirty-six years of joint manufacture, with the compound selected against your actual medium rather than by default
• In-house rubber centre mixes and tests the fluorocarbon compound, so hardness and ageing are controlled
• Galvanized steel wire and multi-layer nylon cord fabric reinforcement, wound for the 4 inch bore
• Participant in drafting GB/T26121-2010, the national standard for flexible rubber joints
• Utility model patent on the joint body, patent number 032418558
• Machined flange faces, flat and parallel, for a gasket seat that holds on the first torque

Support and Services:

• Hydrostatic, dimensional and material checks, plus packing inspection, before each shipment
• 12-month warranty, with TUV, SGS or BV inspection arranged when a project requires it
• Free selection advice on compound and free approval drawings
• Plastic film sleeve inside a plywood case, steel frame added for multi-unit cases
• Online support day and night, after-sales reply within one hour
• Online factory inspection and free samples for evaluation

FAQ:

Q1: Why choose FKM instead of the standard EPDM sphere?

A1: FKM is chosen when the line runs hot, up to 150°C with the special compound, or when the medium is oil, fuel or solvent that would swell and soften an EPDM sphere. For plain water service below 80°C the standard compound is the lower cost choice.

Q2: Does the higher temperature change the dimensions?

A2: No. The 4 inch bore keeps the 150mm face length, 10mm extension, 19mm compression, 13mm lateral travel and ±7.5° deflection of the standard range, so an existing pipe gap can take the FKM unit without rework.

Q3: How do I know which compound my medium needs?

A3: Tell us the medium, its concentration and the working temperature. We come back with a compound recommendation and, where needed, a sample for immersion testing before the order is placed.

Q4: What pressure can the joint be used at?

A4: The joint is built to the pressure class you specify between PN6 and PN40, and every unit is proof tested at 1.5 times that pressure before it leaves the works.

Q5: What is the order quantity and lead time?

A5: A single set is accepted, and the price improves with quantity. Production takes 15-30 working days after payment, with staged delivery possible for a site programme.