第一阶段产品为方型，顶部和底部略小，若是分开就是上下两个梯形。加工时先加工出来两个凹槽状的模型，再把它们合在一起，即成为一个成品。这种产品解决了传统产品不耐腐蚀，易渗漏堵塞的缺点，但是严密性还不够好，抗压性也一般，无法制作大型产品。
In the first stage, the product is square, the top and bottom are slightly smaller, if separated, it is the upper and lower trapezoids. When processing, two groove-shaped models are processed first, and then they are combined to form a finished product. This product solves the shortcomings of traditional products which are not corrosion-resistant and easy to leak and plug, but its tightness is not good enough, and its compression resistance is general, so it can not produce large-scale products.
第二阶段产品基本为横卧的圆柱体，但顶部和底部还是设计为平面。车轮状凹凸面封头开始使用。因为是筒状模具，这一阶段的产品一般采用对接的方法连接结合。这种产品的抗压性能要比第一阶段的好，但是产品的严密性还可以再加以改良，而且这种产品的加工程序复杂，不利于工厂化生产。
In the second stage, the product is basically a horizontal cylinder, but the top and bottom are planar. The wheel-shaped concave-convex head is in use. Because it is a cylindrical die, the products in this stage are usually connected by docking method. The compressive performance of this product is better than that of the first stage, but the tightness of the product can be improved, and the processing procedure of this product is complex, which is not conducive to factory production.
第三阶段的产品也叫波纹玻璃钢化粪池。这种产品保持了第二阶段的车轮状封头设计，但筒体已经设计为波纹状的圆筒状，基本上一次成型，严密性和抗压性能都达到了令人满意的地步。如今还有部分企业还在使用这一阶段的技术。
The third stage product is also called corrugated FRP septic tank. This product maintained the second www.langfangbanjia.cn www.diandongmenl.cn www.yanglaoyuans.cn www.hengshuibanjia.cnwww.dianjiaojii.cnwww.guanjiaojii.cnstage of wheel-shaped head design, but the cylinder has been designed as a corrugated cylinder, basically one-time forming, tightness and compressive performance have reached a satisfactory level. Today, some companies are still using this stage of technology.
第四阶段产品也就是目前普遍采用的产品，有厂家称之为内波纹玻璃钢化粪池。产品外形为光滑的圆筒状，减小了产品的受力面积，但内部每隔一段距离采用方钢预埋加固，酷似波浪起伏，故又得名内波纹玻璃钢化粪池。
The fourth stage product is commonly used at present. Some manufacturers call it internal corrugated FRP septic tank. The shape of the product is smooth cylindrical, which reduces the force area of the product. But the inner part of the product is reinforced by square steel embedded at intervals, which is similar to wave fluctuations. So it is also called the internal corrugated FRP septic tank.