United States Nuclear Regulatory Commission - Protecting People and the Environment

Bulletin 80-09: Hydramotor Actuator Deficiencies

                                                       SSINS No. 6820 
                                                       Accession No.: 
                                                       8002280659 

                                UNITED STATES
                        NUCLEAR REGULATORY COMMISSION
                    OFFICE OF INSPECTION AND ENFORCEMENT 
                          WASHINGTON, D.C. 20555  
                                     
                              April 17, 1980  

                                                     IE Bulletin No. 80-09 

HYDRAMOTOR ACTUATOR DEFICIENCIES 

ITT General Controls (ITT-GC) reported to the NRC two (2) problem areas 
pertaining to their Models AH-90 and NH90 Series Hydramotor Actuators. The 
NH 90 designators depicts nuclear class IE design. Either of the problems 
reported could affect the operation of safety related equipment installed in
nuclear power facilities: 

A.   On December 7, 1979, ITT-GC reported the use of springs having 
     incorrect material installed in Models AH-90 and NH-90 Series 
     Hydramotor Actuators. Instead of 5160 steel, type 1060-1070 steel was 
     used for the No. 1 springs in the actuators. The incorrect spring 
     material does not meet the design strength and upon actuation of 
     greater than 3 inches stroke, a permanent set occurs resulting in a 
     decreased force output of up to 160 lbs, depending on spring 
     combinations used and specific adjustments made to the actuators. About 
     368 defective springs were used between September 1975 and January 
     1978. 

B.   On February 5, 1980, ITT-GC reported that the ITT-GC "Selection 
     Nomograph" for AH-90 and NH-90 series hydramotor actuators represent 
     the actual spring or hydraulic forces only and do not include the 
     effects of friction or residual hydraulic forces. It has been 
     determined that the actuators can have about 100 lbs. of friction and 
     an additional 40 lbs. of residual hydraulic pressure. Use of these 
     nomographs may result in selection of actuators undersized for the use 
     intended. 

C.   Action to be taken by licensees and construction permit holders 

     1.   Each licensee and each holder of a construction permit should 
          determine whether any safety-related system or component in the 
          facility uses an AH90 or NH90 series Hydramotor Actuator 
          manufactured by ITT General Controls. (Note: To assist in this 
          determination a listing of customers that have purchased said 
          actuators and the number of actuators purchased is appended hereto
          as Attachment No. 1. Since some of the Original Equipment 
          Manufacturers (OEM's) may delete the identity of components used 
          in their product, it may be necessary to consult with the OEM to 
          make the required determination.) 

     2.   Operating facilities using said actuators in safety-related 
          systems should: 
.

IE Bulletin No. 80-09                                      April 17, 1980 
                                                            Page 2 of 2 

          a.   Review system functional testing to determining that 
               equipment using the subject actuators are periodically 
               tested. 

          b.   Examine test records to determine whether the functional test
               results conform to system requirements; 

          c.   Verify that ample margin exists with respect to thrust 
               delivered to the load for long term operation considering 
               improper spring material and methods used to select the 
               actuator for a particular application. 

          d.   Take any corrective actions required by the results of items 
               a., b. and c., above. 

     3.   Facilities with construction permits using said actuators in 
          safety-related systems should: 

          a.   Reevaluate actuator size selection in light of the 
               possibility of using actuators with defective springs or 
               which were sized by the "Selection Nomograph" without 
               accounting for internal friction and hydraulic resistance. 
               Said reevaluation should assure that the actuators will 
               perform their intended function. 

          b.   Modify equipment qualification, preoperational and startup 
               test programs, as necessary, to demonstrate the functional 
               adequacy of the Hydramotor Actuator in light of the 
               aforementioned concerns. Particular attention should be given
               to the possibility of defective springs taking a permanent 
               set. 

               Note:     ITT General Controls is presently performing 
                         actuator testing on units supplied by one of their 
                         customers (American Warming & Ventilating Co. Inc.)
                         and revising the methods used to select actuator 
                         application. 

Each licensee or holder of a construction permit should report to the NRC 
within 60 days of the results of actions taken, any corrective actions 
required, and the date when corrective actions were or will be completed. 
The report should be addressed to: 

     U. S. Nuclear Regulatory Commission 
     Director of Reactor Construction Inspection, O.I.E. 
     Washington, D.C. 20555 

Approved by GAO, B180225 (ROO72); clearance expires 7/31/80. Approval was 
given under a blanket clearance specifically for identified generic 
problems. 
.

                              Attachment No. 1 

Customers                                                   Quantities

ACDC Inc, 
Cincinnati, OH                                                   27

American Warming & Ventilating Co., Inc.
Maumee, OH                                                      145 

Copes Vulcan, Inc.
Lake City, PA                                                     2

Fisher Controls Co., Inc.
Marshalltown, IA                                                 38 

Fisher Controls Co., Inc.
Corapolis, PA                                                     4

General Signal Corporation 
West Warwick, RI                                                  2

ITT Hammel-Dahl 
Warwick, RI                                                       4

Joy Manufacturing 
New Philadelphia, OH                                             18

Masoneilan International, Inc.
Norwood, MA                                                      10

Pacific Air Products 
Santa Ana, CA                                                    16 

Posi Seal International, Inc.
No. Stonington, CT                                               14

Powers Regulator Co.
Portland, OR                                                      1

Powers Regulator Co.
Skokie, IL                                                       74

Ruskin Manufacturing Co.
Grandview, MO                                                     4

Valtek, Inc.
Springville, UT                                                   9

                                                       TOTAL    368 
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