Views: 18 Author: Site Editor Publish Time: 2017-07-25 Origin: Site
With the fast development of the production and construction technology of UPVC pipes and fittings and the fire prevention measures, UPVC pipes have been widely used in building drainage engineering. But there always some wrong way during installation process. It causes floor seepage, fittings’ connection leakage, poor water drainage, air pollution and so on, seriously affecting the residents’ usual life. Next, we will tell you about several common UPVC drainage pipe installation errors and tell you the corresponding solutions:
1. Usual installation errors and Countermeasures
1.1 tee and cross
Due to the worker’s negligence, install the tee and cross on the connection of stand pipe and the horizontal pipe. That will cause the joints to form water - lingual flow. The water flow in the transverse branch is not smooth. The pressure fluctuation of the drainage system is big, and the water seal of the sanitary utensil is easy to be destroyed, and the poisonous and harmful gas of the drainage pipeline will invade the interior. The correct way is install Y-TEE or Y-Cross here.
1.2.1 The P-TRAP under the floor drain
Some engineers think that the floor drain with bowl have water seal can deodorize , so do not need to install the P- trap under the floor drain. Then the depth of floor drain’ water seal not reach the standard and be broken. And the resident mistake use and open the bowl and t will block the drainage pipe, will make the smell of sewage escapes into the room, the effects of indoor air quality. According to practical experience and years of relevant data show that the correct approach is to install the P type trap under the floor drain. Recent reports of new hydrostatic seal floor drain - Horizontal floor drain performance is also very excellent.
1.2.2 The P-trap under sink and washing basin
When the design drawings are unknown, the worker often think the p-trap under sink and washing basin install on the floor and under floor is same, but in fact it is not. The p-trap under sink and washing basin is easy to blocked by hair, debris and other debris, it is necessary to open the trap on the check clearing. If the p-trap is installed on the floor below, clearing must be to the downstairs tenants home, family kitchen and toilet are ceiling, this is very inconvenient. The correct approach is S type traps installed in the floor above (but not at the same time series with two traps), so that the household at home at any time can be easily cleaned.
1.3 The 90 deg elbow under stool trap
Use 90 deg elbow to connect the cross branch pipe under the stool trap is not correct. The hydraulic condition is not good as 45 °Elbow. If you use 90 degrees elbow installation, it is best to use the inspection port. The correct installation method is to use a 45 degree elbow to connect with the cross branch pipe.
1.4 compression joint
During the installation of drainage risers, it is often found that leakage or less expansion joints, which is not in line with the requirements of the norm. Because the line expansion of UPVC drainage pipe is larger, the temperature expansion is larger.
The correct installation method is: when the floor height is less than 4 m, the riser shall be provided with a telescopic joint for each floor; when the height is 4 m, the design shall be based on the amount of retractable design, and the design shall not be greater than the maximum allowable amount of expansion of the expansion joint.
1.5 The connection between the horizontal pipe and the standpipe
In some building drainage, the connection between the horizontal pipe and the riser pipe should use 90 degree elbow. This method is a high blockage rate. The reasonable installation method is to use two 45 degree elbow to connect.
1.6 Installation of standpipe and transverse branch pipe
Due to the PVC drainage pipe has great softness, easy to bend. Careless installation will cause the PVC drainage pipe verticality can’t reach the requirements and affect the appearance. And the horizontal branch bending is too large, or even reverse slope, resulting in poor water seepage, joints’ leak, affect the normal use. The correct installation method is that the vertical pipe needs to be hoisted; the transverse branch needs hanging, supporting and correcting the slope, and PVC drainage pipe is installed strictly according to the operating procedures required by the specification.
1.7 Sealing hole after the UPVC pipe cross the floor.
After the pipeline through the floor, some workers just use the fragments of confetti, and other debris were simple after occlusion with cement mortar filling holes, and PVC pipe surface is smooth, and concrete bonding is not very strong, so very easy to cause the floor seepage phenomenon is serious, affecting the normal use. The correct approach is to use civil formwork, pouring less than the floor mark of fine stone concrete plugging hole, if necessary, add waterproof agent.
2 Engineering example
A unit is a multistory residence district around have 108 households. The total construction areais10368㎡, the total cost is 5.621 million. The indoor water supply and drainage part’s cost is around 99,000 yuan. Each household has a washbasin, two wash basin, one a toilet, a bathtub, three floor drain. Started in March 1999, finished on December. The indoor PVC drainage pipe installation works rework several times, direct economic losses up to ten thousand yuan.
2.1 Tee and cross
The original design should use 90 deg Y-TEE and cross. Due to the worker’s negligence, not carefully identify the schema, mistakenly use tee and cross installed in the riser, resulting in all rework. In order to minimize the loss, use 40deg Y-tee and cross instead of the wrong one. The effect is good.
2.2.1 The P-TRAP under the floor drain
The floor drain used in the project with a buckle bowl, and the water seal is 30 mm. Then not install the p-trap under the floor drain is not reach the requirement. Therefore, according to the norms and the actual situation needs, in the above-mentioned should be add the P-TRAP under the floor drain to ensure that indoor air quality.
2.2.1 The P-trap under Sink and washing basin.
As the location of the floor in the construction drawing is not specified, the installation staff made their own claims, they install the P-trap under the floor, which does not meet the regulatory requirements , also not meet the use requirements, resulting in all P-trap’s rework. In order to reduce the loss, after remove the p-trap then using several 45deg elbow, to adjust the direction, easy to connect properly, also the impact is not too big.
2.3 Submerging test of Kitchen and bathroom’s floor
According to the general requirements, the kitchen, bathroom ground should do flood test, check the water seepage situation. But according to Party A requirements, this project kitchen, toilet ground only do 24 h flooding test. Then found that the pipeline floor wear 40% of the place where the water seepage, which is mainly due to the closure of the hole is not strictly in accordance with the norms. The method of treatment is to use the "plugging the king"to brush the seepage point, After the first brush ,the seepage place still have 10%, Then after the second brush almost no seepage, the effect is better.
3 . Conclusion
UPVC drainage pipe is easy to install, but the adhesive should be carefully. Must be strictly to the installation standards. To avoid the joint of UPVC drainage pipe leakages, floor seepage, horizontal pipe slope down, improper use of drainage pipe, installation errors and so on. If need to reworked, the remedy is more difficult, not only affect the appearance, but also cause huge economic losses.
Generally speaking, most of drainage pipe installation errors all have remedial measures, but you should better avoid the second drainage pipe repair. The best way is, in the first water pipe installation, you should consider a variety of factors, install your UPVC drainage pipes and P-traps carefully, this will save you a lot of trouble.