Figure 5-20. - Hydraulic sweep bender with hand pump.
manufacturer's tables and charts are not available, the conduit stub length must be equal to or greater than the minimum shown in table 5-3.
When bending conduit up to 90 degrees with a bender that has a ram travel scale, you should make your bend according to the ram travel scale reading.
An offset bend requires two bends of the same degree. To determine the distance between the two bends, you must first decide on the distance in inches of the offset and the degree of bend your conduit
Table 5-3. - Conduit Size/Deductions/Mininum Stub Lengths
|CONDUIT SIZE||DEDUCT||MINIMUM STUB LENGTH|
|1 1/4||2 3/8||15 13/16|
|1 1/2||2 3/4||18 3/4|
|2||3 1/4||21 9/16|
|2 1/2||4 1/8||25|
|3||4 15/16 28 1/8|
|3 1/2||5 3/4||31|
|4||6 1/2||33 7/8|
routing requires. Remember that the maximum conduit size and offset in inches may restrict your bend. Mark and bend your conduit according to the benders manufacturers' instructions, tables, and charts.
If you have access to a conduit pipe holder (normally for 1 1/4-inch to 4-inch conduit), it will simplify your work by keeping the pipe in perfect alignment at all times, achieving an outstanding bend. When offset bends are being made, the pipe holder permits making the first bend and then reversing the pipe end and making the second bend. The second bend will then be 180 degrees opposite the first bend.
Before using any pipe bender, make sure the quick-lock pins are through the holes in the bottom frame and the eccentric pin is turned clockwise past the ball lock. Also, make sure the correct sides of the pipe support pins are in the proper holes. Failure to ensure correct pin placement could result in damage to the conduit and/or the bender.
Occasionally conduit will require more bending. In this case, place the conduit in the bender and continue bending to the desired degree. This step is not necessary when using the Bending Degree Indicator (used for exact bends and reduces the necessity to correct bending caused by springback) or when using the Bending Degree Protractor because the bend will be accurate.
When you are bending long lengths of conduit, conduit pipe holders are very useful. Check the manufacturer's instruction guide for tables and charts that give vital information about conduit bending kit attachments.
When you have to make a large sweep 90-degree radius bend, you will need to get the operating manual of the bender you are using and follow the suggested procedures for marking the bend spacing and finding the necessary center location.
One of the benders that you may use in the field is the GreenleeTM 880 M2 Lightweight Hydraulic Bender. This bender is designed to make bends up to 90 degrees on rigid conduit from 1/2 inch to 2 inches inclusive. The 15-ton ram, the bending shoes, and the frame unit allow a complete 90-degree bend to be made with one piston stroke. The units of the bender can be rapidly and easily assembled for operation without any tools. By using the bending instructions and the pistonContinue Reading