used to apply load until puUout occurred at a net 

 load at the anchor of 40,000 pounds. Soil taken from 

 the fluke was stiff, hemipelagic clay. 



TEST OPERATION VII 



Three anchors were installed as part of the CEL 

 SEACON II experiment. One anchor was to be part 

 of a construction moor and two were to moor two 

 legs of a tri-legged instrumented cabled structure. 

 This operation constituted the first time the 20K 

 anchor would be used in an actual installation. The 

 sand fluke was chosen for each installation, as per 

 results of Tests 9 and 10. 



Test 24 (5 Aug 74) 



A 3.6-pound charge was considered optimum for 

 this water depth. Once the anchor fired, a test pull of 

 about 25,000 pounds was applied for 10 minutes; the 

 anchor did not pull out. 



This anchor has been in service for over a year. 

 An 8-foot-diameter mooring buoy with a net buoy- 

 ancy of 15,000 pounds is attached via 4,000 feet of 

 wire rope to the anchor in 2,630 feet of water. The 

 140-foot CEL warping tug has moored to this buoy 

 and used it for reaction while pulling the cabled 

 structure under water. Also, a 75 -foot fishing vessel 

 was moored to the buoy for 16 hours during sea state 

 6 sea conditions. Loads were sufficiently great to 

 periodically submerge the mooring buoy. 



to its maximum design water depth. The USS Con- 

 server (ARS) was used as the test platform. 



Twenty-four thousand feet of 2-inch synthetic 

 line was used as the main lowering line. Since part of 

 this line was borrowed, a weak link was placed in the 

 down-haul cable to protect the synthetic line. Geo- 

 logical data indicated that the seafloor was a soft red 

 clay. To make the test more meaningful, the 1-1/2 x 

 3-foot fluke was chosen with a 2.75-pound charge to 

 ensure pullout at a load less than the weak link 

 strength of 27,500 pounds. Lowering to 18,700 feet 

 took about 1-1/2 hours. Firing was not detected with 

 the ship's hydrophone. This was not at all surprising 

 since there was considerable noise interference. Line 

 was retrieved slowly, and it appeared that the anchor 

 had embedded. The dynamometer was not recording 

 the load accurately, but the traction unit behaved as 

 if the load were quite high. It was difficult to keep 

 the line centrally located over the dynamometer 

 shieve; as a result, the loads were incorrect. A post 

 calibration of the dynamometer with the line angled 

 in the same direction showed that the peak pullout 

 load was between 17,000 to 24,000 pounds. 



TEST OPERATION IX 



The purpose of these tests was to supplement the 

 limited test data for anchor performance in a rock 

 seafloor. Tests were performed off Anacapa Island 

 (about 20 miles from Port Hueneme) from the CEL 

 warping tug in 60 feet of water. 



Tests 25 and 26 (5 Aug 75) 



Test 28 (6 Dec 74) 



Both anchors were installed with 3.25-pound 

 charges. The reduced charges were chosen because the 

 actual in-service loads would not exceed a few 

 thousand pounds. Each anchor was embedded 25 feet 

 after setting the anchor flukes. These depths were 

 accurately measured with a transponder placed 50 

 feet above the gun assembly. Test pulls of 15,000 

 pounds were applied to each anchor for 10 minutes. 



TEST OPERATION VIII 



The purpose of this test (Test 27, 23 Sep 74) was 

 to verify the performance of the 20K anchor at close 



Divers located a flat, rock seafloor in 60 feet of 

 water. The rock projectile was used with a 

 3.75-pound charge. Firing occurred, and divers were 

 sent to photograph the anchor. Penetration was deep, 

 not into competent basalt, but into a cemented rock 

 conglomerate overlying sand. The open socket 

 attached to the fluke was fractured; the piston 

 apparendy ejected prematurely and impacted the 

 socket. This had not occurred in two previous tests in 

 rock (Tests 11 and 12), because solid rock was 

 encountered, and lateral projectile movement was 

 minimized. Flukes fabricated subsequent to this 

 operation will be modified by welding the main plates 

 at 180 degrees vice 140 degrees. 



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