Double Sphere Rubber Expansion Joint EPDM PN16 Tie Rod Design for HVAC Chilled Water Piping DN65-DN300

Product Description:

The double sphere rubber expansion joint is a twin-bellows flexible connector installed between pump discharge, chiller headers and pipe risers. Two independent rubber spheres share the movement, so each convolution carries only half of the total displacement. The result is lower stress in the rubber body, longer flex life under continuous pump cycling and a shorter installed face-to-face length compared with two single sphere joints in series.

This model is built on an EPDM rubber body with a multi-layer nylon cord carcass, steel wire pressurized rings and hot dip galvanized carbon steel flanges drilled to DIN PN16. External tie rods with limit nuts control axial extension, which keeps the bellows protected when the line is tested at pressure or when a pump starts against a closed valve. Every unit is hydro-tested before packing and can be supplied with a dimensional drawing for approval before production.

Typical service is chilled water, condenser water, hot water up to 120°C, air and mild chemical media in HVAC plant rooms, district cooling stations and industrial process lines. For oil, acid or solvent service the same body is offered in NBR, CR or FKM, and PTFE lining is available for aggressive media.

Product Applications:

• HVAC chilled water and condenser water piping
• Chiller plant rooms and air handling unit connections
• District cooling and district heating networks
• Pump suction and discharge lines
• Water supply and drainage systems
• Petroleum, mining and metallurgical process piping
• Environmental protection and paper industry lines

Product structure:

Technical Parameters:

Product features:

Twin sphere body: two rubber bellows absorb axial, lateral and angular movement at the same time, reducing pipe stress and transmitted noise in one compact fitting.

Galvanized flange finish: machined sealing face with anti-corrosion and anti-rust treatment, full face sealing available for soft gaskets.

Tie rod limit assembly: galvanized rods with adjustable nuts hold the joint at the required installed length and prevent over-extension during pressure testing.

High elasticity EPDM compound: ozone and ageing resistant, suitable for outdoor and plant room installation from -15°C to 120°C.

Wide size range with more than 2000 sets of moulds: DN15 to DN4000 with intermediate sizes and custom face-to-face lengths produced on request.

After-sales service commitment letter:

• The shelf life of our company's sold products is 1 year (from the date of the last batch of handover and acceptance). During the warranty period, the products shall be guaranteed with "three guarantees", namely "repair guarantee", "replacement guarantee", and "return guarantee".
• After the warranty period expires, our company implements a lifetime warranty for the sold products, and only charges a cost fee for the replacement of standard parts and seals.
• During the installation and debugging period, our company sends maintenance personnel to the site to assist in the installation and debugging until the debugging is completed and the user is satisfied.
• During the operation of the equipment, if a temporary malfunction occurs, upon receiving your repair notice, we respond within 2 hours and send personnel to the site for resolution within 48 hours.
• Starting from the date of equipment operation, we will inquire about the equipment operation status every six months by phone or by visiting the site, and record the information obtained.

Promisor: Henan Liwei Industrial Co., Ltd

FAQ:

Q1: What is the difference between this double sphere joint and a single sphere joint?

A1: A double sphere joint has two rubber bellows in one body, so the same total movement is shared by two convolutions. This lowers the stress in the rubber, gives a longer fatigue life and absorbs axial, lateral and angular movement in a shorter installed length.

Q2: Which sizes and pressures are available?

A2: The standard range is DN65 to DN300 with face-to-face lengths from 115 mm to 245 mm, working pressure PN6 to PN40. Sizes from DN15 to DN4000 and special lengths are produced with our own moulds.

Q3: Why are tie rods supplied with the joint?

A3: Tie rods with limit nuts control axial extension. They protect the bellows during pressure testing and on pump start-up, and they keep the joint at the correct installed length on chilled water and condenser water lines.

Q4: What information do you need for a quotation?

A4: Please confirm the nominal diameter, flange standard and drilling (DIN, ANSI, JIS or BS), working pressure, media and temperature, and the required movement. We will return a drawing, a price and a delivery schedule.