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....INSTRUCTIONS FOR TESTING CONCRETE CYLINDERS USING A COMPRESSION TESTING MACHINE WITH DIGITAL CS-100-2A AND A SPX MODEL B HYDRAULIC PUMP ....



1. Sample Preparation

Prepare the concrete sample in accordance with ASTM C-39. Use the capping method of choice. If using pad caps, be sure to have the appropriate durometer pads in the bases. Be sure to thoroughly clean the bases on a regular basis both inside and out. Concrete debris will build up on the inside of the steel bases. This will cause excessive corner breaks on samples if the debris is allowed to build up. Use a blunt instrument to remove the debris and reinstall fresh pads.

When using pad caps, the rule of thumb is to break 100 cylinders, flip the pads over test 100 cylinders and throw the pads away. Typical life expectancy of pads is 200 breaks. Over usage of pads will cause unacceptable tests results. When installing pad caps on the specimen, always put the bottom of the specimen in the bottom pad cap base. The bottom of the specimen is the side which sits in the bottom of the cylinder mold.

2. Preparing for application of load to the sample

Take your capped specimen and insert it into the testing machine.

Center the specimen in the upper and lower pad bases.

Center the specimen in the testing machine.

If you have a machine with a piston on the top of the loading frame, center the specimen on the top platen.

If you have a machine with a piston on the bottom of the loading frame, center the specimen on the bottom platen.

This is very important if you want accurate testing results!!

3. Application of Load

Your testing machine will have a Digital Display for load indication.

Please review the features of the Digital display before attempting to test samples.

This information is found in the Digital Manual.

Each model of digital offers different ways to input critical information regarding your test. If an authorized calibration company is performing setup, please ask to be instructed on digital operation and features at time of setup. If this is not the case….PLEASE READ THE MANUAL.

Your machine is fitted with a CS-100-2A indicator.

This indicator allows for entry of specimen dimensions, this will allow you to show your loading rate in Stress/sec if the rate of loading menu is set up for this function. It is important to enter the proper specimen dimensions prior to testing in order to show the loading rate properly.

C-39 specifies the loading rate at 35 PSI/sec +/- 7 PSI.

4. The Pump

The pump on your machine is an SPX Model B pump

The control valve is a 4 position 3 way valve built by SPX

This pump is equipped with an external dump valve, sight glass with temperature gauge, and an oil drain plug

The Pump uses TURBINE GRADE HYDRAULIC FLUID ALTRA R&O 150 OR BETTER as the fluid of choice.

The reservoir should be ¾ full of fluid.

The vent is located in the Red colored plug located on the back side of the reservoir.

This pump is a 15 minute duration unit. Please turn off the pump motor whenever the machine is idle.

This will prolong pump life and minimize fluid temperature.

The Valve (See figure 2, figure 3, & figure 4)

The valve contains a 4 position lever and a star shaped flow control knob, and an external dump valve.

The 4 position lever is labeled RETRACT, HOLD, METERED ADVANCE, RAPID ADVANCE. (See Figure 2)

You should only use this valve in the METERED ADVANCE or RAPID ADVANCE positions. Use the dump valve to release the load or pressure from the machine. (Figure 3)

The lever on the right side of the valve is the pressure/release lever or DUMP VALVE. (Figure 3)

In the upright position (with the lever straight out) the pump will Build pressure. (Figure 4)

In the down position (with the lever facing down) the pump will release pressure and allow the piston to retract. (Figure 3)

The lever on the left is the rapid advance/controlled rate lever. (Figure 2)

With the knob pulled toward the star shaped knob, the pump is in rapid advance.

Note: This means the piston will move rapidly. Care must be taken when using the rapid advance function. The piston only has 2 1/2 inches of stroke. If left in the rapid advance position for too long, the piston will overextend causing a release of oil from the piston assembly. Contact CSI at 724-867-6664 if this occurs to prevent extensive damage which would void your warranty.

The rapid advance lever is used only to position the piston close to th sample for zeroing purposes, or to preload the sample once zeroing has been performed. Never use the rapid travel position to test the cylinder to total failure. This will provide inaccurate test results. The stem in the center acts like a water spigot (Figure 2). Counter-clockwise increases the rate of force application per second. Clockwise decreases the rate. Once the proper rate is achieved, you can leave the stem at that setting and the machine will continue to load at the proper rate.

You are now ready to test your specimen.

5. Performing a Test.

Once the specimen dimensions and sample information are entered into the digital, insert the sample as described earlier.
2. Ensure the piston is completely retracted using the dump valve located on the side of the pump reservoir.
3. Lift up on the dump valve lever.
4. Have the flow control valve handle in the Metered Advance position.
5. Turn on the pump.
6. Rotate the control valve to Rapid Advance until approximately 1/4"of daylight exists.
7. Immediately move the control valve to the Metered Advance position.
8. Press the Zero button on the digital display.
9. Wait 3 to 4 seconds until the load display blinks.
10. Rotate the valve back to Rapid Advance and preload the sample.
11. Rotate the valve back to Metered Advance.
12. Wait for a second or two and view the load rate display which is located directly under the load display on the digital.
13. If the load rate does not show on the bottom of the display, dump the pressure using the dump valve. Do not proceed with the test. If you do the peak load will not be displayed at test end. Repeat zeroing procedure at step 3.
14. If the rate of load shows up, follow the load rate and keep it at 35 PSI/sec.
15. You may have to turn the star shaped knob on the flow control valve CW or CCW to achieve proper speed.
16. Once you get your speed set, leave the star shaped knob in that position, continue to load until the sample fails.
17. You will notice the rate of loading will drop before the sample fails. Do not attempt to compensate during yield.
18. Unload the machine after failure by using the dump valve.
19. Do not use the retract position on the control valve. This causes sever wear on the control valve and may void your warranty.
20. We have installed this dump valve to improve control valve life.
21. After the test is complete you will see the Peak Load and Peak Stress displayed on the digital. Record these values or download the information to your computer/printer depending on how you set up your system.
22. Remove all debris and wipe down cap bases.

You are now ready to test your next specimen.



For more information on calibration services or digital retrofits please contact us.

CALIBRATION SERVICES, INC.

 


300 Buttertown Road
Emlenton, PA 16373
(724) 867-6664 or (800) 793-1870
FAX (724) 867-1346

 

 
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