The type of door that will work best for your shower depends on the design of your shower, the size of the opening and the practical space considerations that determine how your door should open. Showers generally fall into three types of designs.
Preload is the tension created in a fastener when it is tightened. This tensile force in the bolt creates a compressive force in the bolted joint known as clamp force. For practical purposes, the clamp force in an unloaded bolted joint is assumed to be equal and opposite of the preload.ither is acceptable, however a torque value defined for tightening the head does not necessarily apply to tightening the nut. Tightening the head vs. the nut can result in different nut factors and therefore change the torque required to achieve proper preload.
Preload is defined as the actual stretch or tension on the ventricular myocardium prior to contraction (Totora & Gabowski 2002). The greater the preload on the myocardium (the larger the amount of blood that has filled the heart during diastole), the greater the contraction will be.