Technical characteristic Adopting the advanced production line crack detecting, quenching, the continuous overall tempering and sand blasting processes to achieve higher mechanical strength ability with overall good performance. 1 íóthe thread is cut by the special-purpose numerical control lathe which keeps the rod body still when cutting the threads. The special process could ensure the high precision of the thread with better reliability and life-span. 2 íócoupling phosphor or copper coated to achieve good wearing-resistance ability and anti-thread gluing ability. Tubing size in od in(mm ) wall in(mm ) grade length ft(mm ) Standard eue 23/8 2.375(60.33 ) 2.594(65.90 ) 0.190(4.83 ) j55 n80 L80 c90 T95 p110 28 í½32(8530 í½9750 ) 27/8 2.875(73.03 ) 3.094(78.60 ) 0.217(5.51 ) 31/2 3.500(88.90 ) 3.750(95.20 ) 0.254(6.45 ) Coupling size in od in(mm ) min length in(mm ) grade end width in(mm ) weight lbs(kg ) Standard eue standard eue standard eue standard eue 23/8 2.875(73.03 ) 3.063(77.80 ) 41/4(107.95 ) 47/8(123.83 ) j55 n80 L80 c90 T95 p110 3/16(4.76 ) 3/16(4.76 ) 2.82(1.28 ) 3.43(1.55 ) 27/8 3.500(88.90 ) 3.668(93.20 ) 51/8(130.18 ) 51/4(133.35 ) 7/32(5.56 ) 5.15(2.34 ) 5.29(2.40 ) 31/2 4.250(108.00 ) 4.500(114.30 ) 55/8(142.88 ) 53/4(146.05 ) 1/4 (6.35 ) 8.17(3.71 ) 9.03(4.10 ) Main technical parameter