roll-back system, stripping jacks, form raiser

[Т.Ю.]

Помогите, пожалуйста, разобраться с устройствах подъема самоподъемной опалубки - roll-back system, stripping jacks:
The system in Figure 8 uses a roll-back system in which the form is mounted on a trolley system that allows it to be stripped, rolled back and then moved to the next level. Another type of self-raising form uses stripping jacks to remove the forms away from the finished concrete and also to pull the form raiser away from the concrete, allowing it to move to the next anchoring location by the raising rams. The stripping jacks are then reversed, bringing both form and form raiser to the anchoring location.
спасибо заранее.