| The Challenge |
| This application was for a constant force compression spring to connect two pipeline "PIGS" together. (A pipeline pig is a machine that enters into the actual pipeline from an offshore oil rig supplying oil or gas to the mainland.) The "pig" records data, such as the condition and reliability of the pipe wall, as it moves along with the flow of oil or gas.
Originally, a traditional wire wound spring was used, but the long term compression forces caused performance deterioration. The readings from the PIGS were becoming more and more unreliable as pulsing shockwaves in the pipeline hit the PIGS along their journey. The spring also needed guaranteed flat end surfaces and the piano wire material was corroding in the hostile atmosphere. Reliability was poor. |
| The Solution |
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The customer gave us the overall dimensions, we could then guarantee a fixed outside - inside diameter, length, an exact compression spring rate and flat end surfaces. All of these features could be supplied in a material that gave much better resistance to the corrosive atmosphere. The HELI-CAL® Flexure also enabled far tighter manufacturing tolerances to be put into the design. "PIG" reading accuracy increased by 50%. |
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HELI-CAL Flexure Precision Machined Spring # 2261X1 Rev B
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