Globe Technologies Corp. fusible link, pneumatic fusible valve, fusible loop, fusible chain, flow restrictor, fusible tube

For Your Information

Inspection, Maintenance, Testing and Replacement Frequency of Fusible Links Used in Fire Doors

After further investigation and study of the Inspection, Maintenance, Testing and the Replacement frequency of Fusible Links that are used as heat detectors with Fire Doors, Globe Technologies Corporation (manufacturer of Fusible links) advise its Customers to the following conclusions:

1. Fusible Links shall be subjected to axial tensile loads only. The loads shall not exceed the maximum design load of the link.

2. Fusible Links shall not be subjected to high temperatures that exceed its maximum acceptable ambient temperatures. Field verification of the maximum anticipated ambient temperature shall be evaluated prior to the selection of the temperature rating of the Link.

3. Fusible Links shall not be painted or coated. Fusible Links shall be replaced immediately if painted or sprayed with chemicals.

4. All Fusible Links shall be inspected and examined at least once annually for corrosion, soldered joint cracks, paint residue, chemical residue, or other foreign material that will impair the performance of the Link. In such cases the Fusible Links shall be replaced.

5. NFPA 80 1999 edition paragraph 15-2.4.3 and Factory Mutual 1-23 Data sheet requires that all Fire Doors shall be tested at least annually for automatic release and full closure. It is of our opinion and Factory Mutual recommendation that the Fusible link shall be fused during the testing to simulate a fire condition.

6. All Fusible Links shall be replaced one a year. The Links shall be replaced sooner during annual inspection if the conditions in (4) exist. The Fusible alloy that is used in the manufacturing of the Fusible Links undergoes a phenomenon known as Creep or Cold flow. It is the continuous application of load versus time that will ultimately fracture the Link. We recognize that NFPA 80 does not address the replacement frequency of the Fusible Links. However, it is stated that the Fusible Links shall be installed according to the manufacturer.

7. Globe Fusible Links are stamped with the year of manufacturing. The stamped year shall be used to determine the one year replacement period.

Maintenance, inspection and replacement of fusible links

NFPA Bulletin 96 section 11.4.7 indicates that "Cleaning Chemicals shall not be applied on fusible links". Globe Technologies Corporation strongly recommends that the Fusible links be wiped and cleaned with a wet cloth and not by the application of cleaning chemicals or steam.

Product Reminder

On July 1, 2002, all manufacturers of Dynamic Fire, Combination Fire/Smoke Dampers must comply with new UL requirements: DYNAMIC CLOSURE TEST. Globe's (PFV) installed with pneumatic actuator and Globe's (EFL) installed with Electric actuator utilize a fast standard responsive fusible link coupled with a better positioning of the fusible link in the heated airflow will respond faster than the Fire/Smoke dampers equipped with only a fusible link or a bi-metallic link when subjected to the new UL heated airflow tests. You can install them in small and large dampers irrespective of the applied spring tension.

The PFV and the EFL are Underwriters Laboratories listed thermal release devices listed in the following temperatures: 135° F, 155° F, 165° F, 212° F and 280° F. We are working with U.L. to obtain a 350° F listing for both products.