COLLAPSE OF TEXAS TOWER NO. 4 169 



torque. These bolts were torqued to 1,300 foot-pounds. They were 

 found to be holding at 1,300 foot-pounds after slight sea conditions — 

 that is, on checking at a later date, a day or two later, after we had 

 encountered slight sea conditions. 



Mr. Kendall. At that time, Mr. Crockett, was any consideration 

 or particular attention given to a possible deterioration in the pin 

 connections, particularly on the A B side of the tower ? 



Mr. Crockett. We examined all the pin connections at the minus- 

 23 -foot level and found that they were reasonably within their 

 tolerance. 



In order to ascertain whether a pin was exactly within its tolerance, 

 it would have to be opened up ; that is to say, the locking devices on the 

 extremities of the pin would have to be removed to determine the 

 clearance between the pin diameter and the diameter of the hole. This 

 was not done. 



However, we could ascertain very slight motion, which was, say, 

 possibly an eighth of an inch in clearance, which we felt at that time 

 was within the design tolerance. 



Mr. Kendall. This is a survey that was made approximately 1 

 year after the tower was in operation ? 



Mr. Crockett. That is so. 



Mr. Kendall. What did you find with reference to the collar con- 

 nections secured by the Dardelet bolts ? 



Before you answer that, let me ask you, Mr. Crockett, are Dardelet 

 bolts ordinarily used for a permanent fix or a temporary fix ? 



Mr. Crockett. It could be used, I suppose, as a permanent fix. 

 However, it has been my small experience in the past to use them 

 temporarily. 



Mr. Kendall. Now, will you go ahead and tell us what you found 

 with reference to the collar connection and the Dardelet bolts? 



collar connections in vertical motion on leg 



Mr, Crockett. The A caisson collar at the minus-65- to 70-foot level 

 was cleaned of marine growth over its entire connection area. We 

 found the caisson in the way of the top and bottom edges of the collar 

 shined to bright bare metal. This bright metal, approximately 2 

 inches in width, was caused by vertical motion in the collar. 



Upon further investigation, we found that several of the jam nuts 

 and double nuts that secured the 2-inch collar hold bolts had slackened 

 away from the holding nut an inch or two. 



Mr. Kendall. So you found that collar was sliding up and down 

 on the caisson ? 



Mr. Crockett. Yes, sir. 



Mr. Kendall. And that the bolts themselves had slacked to how 

 much? Two inches? 



Mr. Crockett. Some of them were off in fixture as much as 1 to 2 

 inches. This was not the case in all the bolts. However, we found 

 that the collar bolts have very slight, if any, torque when we endeav- 

 ored to torque the connection. 



Mr. Kendall. Then did you conclude from that that the fix that 

 involved the collar connection was not holding ? 



Mr. Crockett. Say that again, please. 



