pistons in a pair provides an effective stroke twice the length of a single assembly stroke in a particular embodiment a double cylinder system is used as a pickup system for elevating equipment along a mast in a well workover rig application_number US 91311778 A description a coiled tubing system including double cylinder apparatus according to the present invention is shown generally at 10 in fig1 and 2 mounted on the flatbed 12 of a trailer truck 14 while the improved system of the present invention may be utilized in a variety of applications including stationary as well as mobile assemblies and such mobile arrangements may take several forms including barge mounts or unitized carrier mounts a trailer mounted coiled tubing application is shown and discussed herein by way of illustration rather than limitation the flatbed 12 supports a tubing reel assembly 16 mounted on a skid 18 a power unit 20 mounted on a skid 22 and a control house 24 mounted on a skid 26 the control house 24 includes most or all of the controls necessary for operating the various hydraulic and pneumatic systems employed with the coiled tubing apparatus and is otherwise conventional the power unit 20 includes the necessary power means used in operating the coiled tubing apparatus including motors a pneumatic compressor and a hydraulic pump both the power unit skid 22 and the control house skid 26 are anchored against lateral movement along the flatbed 12 by hold down pins 28 shown in more detail in fig1 the frame of the power skid 22 for example is equipped.