<ARTICLE> 5
<MULTIPLIER> 1,000
       
                                                  
<PERIOD-TYPE>                   3-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-1998             DEC-31-1997
<PERIOD-START>                             JAN-01-1998             JAN-01-1997
<PERIOD-END>                               MAR-31-1998             MAR-31-1997
<CASH>                                             270                     796
<SECURITIES>                                    15,059                  17,521
<RECEIVABLES>                                   42,350                  41,044
<ALLOWANCES>                                       600                     600
<INVENTORY>                                     38,427                  30,078
<CURRENT-ASSETS>                                97,416                  90,750
<PP&E>                                         254,375                 250,727
<DEPRECIATION>                                 176,648                 175,249
<TOTAL-ASSETS>                                 217,631                 209,752
<CURRENT-LIABILITIES>                           26,555                  21,896
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                         6,792                   6,792
<OTHER-SE>                                     151,840                 148,513
<TOTAL-LIABILITY-AND-EQUITY>                   217,631                 209,752
<SALES>                                         73,637                  60,041
<TOTAL-REVENUES>                                73,637                  60,041
<CGS>                                           60,372                  51,943
<TOTAL-COSTS>                                   67,189                  58,296
<OTHER-EXPENSES>                                     0                       0
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                                   0                       0
<INCOME-PRETAX>                                  6,937                   2,329
<INCOME-TAX>                                     2,497                     815
<INCOME-CONTINUING>                              4,440                   1,514
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                     4,440                   1,514
<EPS-PRIMARY>                                      .67                     .23
<EPS-DILUTED>                                      .66                     .23