Tapered Rod String Analysis
Spreadsheet
26 rows x 10 columns
| A | B | C | D | E | F | G | H | I | J | |
|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Tapered Rod String Analysis | |||||||||
| 2 | ||||||||||
| 3 | Input Parameters | |||||||||
| 4 | Plunger Diameter | 1.5 | in | |||||||
| 5 | Fluid Level Above Pump | 500 | ft | |||||||
| 6 | Fluid Specific Gravity | 0.85 | ||||||||
| 7 | ||||||||||
| 8 | Fluid Load | |||||||||
| 9 | Pump Depth (rod string length) | 5000 | ft | |||||||
| 10 | Net Lift (depth to fluid level) | 4500 | ft | |||||||
| 11 | Fluid Gradient | 0.36805 | psi/ft | |||||||
| 12 | Plunger Area | 1.767145868 | in2 | |||||||
| 13 | Fluid Load on Plunger | 2926.791165 | lb | |||||||
| 14 | ||||||||||
| 15 | Rod String (top taper first, leave unused rows blank) | |||||||||
| 16 | Taper | Diameter (in) | Length (ft) | Area (in2) | Weight in Air (lb) | Buoyant Weight (lb) | Air Weight Below (lb) | Load at Top (lb) | Max Stress at Top (psi) | Stretch (in) |
| 17 | Taper 1 (top) | 0.875 | 2000 | 0.6013204689 | 4084.168624 | 3639.811078 | 4500.920525 | 10577.82261 | 17590.99043 | 12.59866776 |
| 18 | Taper 2 | 0.75 | 3000 | 0.4417864669 | 4500.920525 | 4011.220372 | 0 | 6938.011536 | 15704.4456 | 14.06268 |
| 19 | Taper 3 | |||||||||
| 20 | Taper 4 | |||||||||
| 21 | Total | 5000 | 8585.089149 | 7651.03145 | 26.66134776 | |||||
| 22 | ||||||||||
| 23 | String Loads | |||||||||
| 24 | Peak Polished Rod Load | 10577.82261 | lb | |||||||
| 25 | Min Polished Rod Load | 7651.03145 | lb | |||||||
| 26 | Maximum Rod Stress | 17590.99043 | psi |
Description
Tapered sucker rod string analysis for up to four rod sizes. Calculates each taper's weight, the load and stress at its top, and its stretch, plus the string's simple polished rod loads.
Parameters:
- dp: Plunger diameter (in)
- h_sub: Fluid level above pump, the fluid standing over the pump in the annulus (ft)
- SG: Fluid specific gravity (dimensionless)
- d1–d4: Rod diameter of each taper, top taper first (in)
- L1–L4: Length of each taper (ft). Leave a row blank to use fewer tapers.
Method: static loads, without API 11L dynamic factors. The pump depth is the length of the rod string, and the fluid load acts over the net lift: the pump depth less the fluid level above the pump, which is the depth from surface to the fluid level in the annulus. The fluid gradient is 0.433 × SG. The top of each taper carries the fluid load plus the buoyant weight of that taper and every taper below it, so each rod size is checked for stress at its top. A taper stretches under the fluid load, its own weight and the weight of the tapers hanging below it, with rod weights taken in air as PO.RP.Rod.Stretch.RodWeight does. A string of one rod size gives the same answer as the Rod String Stress Analysis blueprint.
How to use this blueprint
- In Excel, go to the Petroleum Office ribbon tab and click Blueprint Manager
- Search for Tapered Rod String Analysis
- Click on the blueprint to preview
- Click Insert to place it into your worksheet. Modify the input values to match your data.