201 vs. 304 Comparison Test

Comparative Load Test
April 16, 2007American Stainless Tubing, Inc. (ASTI) submitted two lots of stainless steel tubing for load/deflection testing. The first lot samples were 53 inches long and the second lot samples were 57 inches long. All of the tubing tested was 1.250” OD x .062” wall thickness. Five of the samples are Type 304L and six of the samples are Type 201HP Stainless Steel to ASTM-554. All of the tubes were polished to a 180 grit finish. All material was manufactured by the same mill.
Load Test
Test No. 1 Mid-Point Load Test

The 53 inch long tubes were subjected to a center point load of 330 lbs. These tests were performed in an Instron Testing Machine, Model 4206 (Electro Mechanical System). The base of the machine was extended using an I-beam. Figure 1-1 shows the machine set-up prior to testing. The load was applied through a plastic block with a special ID configuration to prevent surface indentation. The ends of each tube were firmly clamped in place on the I-beam. Figure 1-2 shows the test set-up prior to applying the load. Each tube was held under load for a period of 10 minutes and the permanent deflection was measured after load removal. Figure 1-3shows the tube under load. The deflection-under-load readings were directly recorded by the computer. The results of this test are summarized in Table 1.

Test No. 2 Uniform Load Test

The 57 inch long tubes were subjected to a distributed load test of 60 lbs. every six inches, beginning at 4-1/2 inches from one end for a total of nine locations. Figure 2-1 shows the set-up prior to testing. Each tube was held under a total load of 540 lbs for a period of 10 minute. The initial deflection was recorded using a dial indicator after the 10 minute period. Figure 2-2 shows the tube during the load test. The permanent deflection was recorded using a dial indicator after the load was removed. Figure 2-3shows the permanent deflection of the tube.The load test was conducted at the University of Pennsylvania by Dr. Alex Radin. Dr. Radin is the director of the Mechanical Testing Center.

Fig 1-1

Fig 1-1

Fig 1-2

Fig 1-3

Fig 2-1

Fig 2-2

Fig 2-3