> For the complete documentation index, see [llms.txt](https://drilling.intelie.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://drilling.intelie.com/physical-models/surge-and-swab/pipes-code.md).

# Pipes Functions

## **Pressure along of the drill string**

![Pressure along of the drill string](https://lh4.googleusercontent.com/1wXvwi93mf2vOvSd5TmkBDag2yrPb0H2HkOuQHimDZQO0tNeFAAI32ocg1HAowGJ-3M5XSvzZps7Ta59WGMsy-7lEjJt4QIzHhSoOFlktCH3WmfbxJKZC449SlF69JOuKspnW0R2)

### Surge

Computes surge pressure along the specified well with the specified pipe speed)

```javascript
og.model.surge.pressure(
         newmap("wellId", "{well_id}",  
                "bitDepth", value_m,
                "pipeSpeed", value_m/s, 
                "computationUom", 'Pa', 
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

**Output: Pressure Surge (Pa) vs Depth**

### Swab

Computes swab pressure along the specified well with the specified pipe speed

```javascript
og.model.swab.pressure(
         newmap("wellId", "{well_id}",  
                "bitDepth", value_m,
                "pipeSpeed", value_m/s, 
                "computationUom", 'Pa', 
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

**Output: Pressure Swab (Pa) vs Depth**

**Example Pipes:**

```javascript
--Swab ECD
=> og.model.swab.pressure(newmap("wellId","11","pipeSpeed", 0.05)) every batch
=> @for => @yield => {swab.pressure} as Swab_pressure, depth

--Surge ECD
=> og.model.surge.pressure(newmap("wellId","11","pipeSpeed", 0.05)) every batch
=> @for => @yield => {surge.pressure} as Surge_pressure, depth
```

## **Equivalent Pressure along the drill string**

![Surge and Swab ECD  along of the drill string](https://lh6.googleusercontent.com/c4efKJo226moI0j-LtEs7bsCl2U8CtOoM9urCy7Q9h8S1LrEL0xS7B7RirGTpLxutvbo8EsO0WU-WjcmoHYJzzq2ck4LPtzBx2gWtRxAz2goMUmboI71qoybshqZ05M1E1VPCfAI)

### Swab

Computes swab density along with the specified well with the specified pipe speed

```javascript
og.model.swab.pressure(
         newmap("wellId", "{well_id}",  
                "bitDepth", value_m,
                "pipeSpeed", value_m/s, 
                "computationUom", 'kg/m3', 
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

**Output: ECD swab (kg/m3) vs Depth**

### Surge

Computes surge density along with the specified well with the specified pipe speed

```javascript
og.model.surge.pressure(
         newmap("wellId", "{well_id}",  
                "bitDepth", value_m,
                "pipeSpeed", value_m/s, 
                "computationUom", 'kg/m3', 
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

**Output: ECD surge (kg/m3) vs Depth**

## **ECD and Pressure at a given depth**

### Surge

Computes surge equivalent circulating density at given depth

```javascript
og.model.surge.pressure(
         newmap("wellId", "{well_id}",  
                "bitDepth", value_m,
                "pipeSpeed", value_m/s, 
                "computationUom", 'kg/m3', 
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean,
                "atDepth", value_m)
)
```

**Output: ECD surge (kg/m3)**

### **Swab**

Computes swab equivalent circulating density at given depth

```javascript
og.model.swab.pressure(
         newmap("wellId", "{well_id}",  
                "bitDepth", value_m,
                "pipeSpeed", value_m/s, 
                "computationUom", 'kg/m3', 
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean,
                "atDepth", value_m)
)
```

**Output: ECD swab (kg/m3)**

**Example Pipes:**

```javascript
--Swab ECD

=>og.model.swab.pressure(
           newmap('wellId','9', 
                  'computationUom', 'kg/m3', 
                  'pipeSpeed', 0.01, 
                  'bitDepth', 1000, 
                  'minSectionLength', 250))->result:seq at the end
=> @chain
=> {swab.pressure}#curve_unit_convert(kg/m3,'lbm/galUS') as {Swab}, depth#curve_unit_convert('m',@@depthOutputUnit) as depth

--Swab ECD
=>og.model.surge.pressure(
           newmap('wellId','9', 
                  'computationUom', 'kg/m3', 
                  'pipeSpeed', 0.01, 
                   'bitDepth', 1000, 
                   'minSectionLength', 250))->result:seq at the end
=> @chain
=> {swab.pressure}#curve_unit_convert(kg/m3,'lbm/galUS') as {Surge}, depth#curve_unit_convert('m',@@depthOutputUnit) as depth
```

## **Maximum running speed**

![Max trip velocity vs Depth](https://lh5.googleusercontent.com/2_9LzgutZgAYQ1Z9xN3rnZyN--M7rna18gk52bj_2E3HY3heOzYhOAQEjY6JcSD_loxcwgOpLjK0VwZUyU1dhedgXMjciX2TKOTNRrEBo2z3NP4mHAMFxJY0chMH9-6oCsDOyKvM)

### Surge

Computes maximum pipe speed profile on surge along the specified well

```javascript
og.model.surge.maxPipeSpeed(
         newmap("wellId", "{well_id}",  
                "depthLowerBound", value_m,
                "initialBitDepth", value_m, 
                "bitStepSize", value_m,
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

**Output: Max Surge Speed (m/s) vs Depth**

|

**PARAMETER | TYPE | DOMAIN | REQUIRED? | DEFAULT**

**wellId | String | Integer Strings | Yes | ---**

**drillingSectionIndex | Integer | >= 0 | No | ---**

**bitDepth | Double | >= 0 | No | ---**

**atDepth | Double | >= 0 | No | ---**

**minSectionLength | Double | 0 <= x <= maxSectionLength | No | 0**

**maxSectionLength | Double | >= minSectionLength | No | Infinity**

**closedEnded | Boolean | {true, false} | No | true**

**depthLowerBound | Double | Reals | No | 0**

**bitStepSize | Double | > 0 | No | 20**

\| | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |

### Swab

Computes maximum pipe speed profile on swab along the specified well

```javascript
og.model.swab.maxPipeSpeed(
         newmap("wellId", "{well_id}",  
                "depthLowerBound", value_m,
                "initialBitDepth", value_m, 
                "bitStepSize", value_m,
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

**Output: Max Swab Speed (m/s) vs Depth**

**Example Pipes:**

```javascript
=> og.model.swab.maxPipeSpeed(
      newmap("wellId", "11", 
             "depthLowerBound", 50, 
             "initialBitDepth", 1000, 
             "stepSize" 50))->result:seq at the end
=> @for => @yield => -{swab.maxPipeSpeed}# as {Max Swab Speed}, depth# as depth

=> og.model.surge.maxPipeSpeed(
       newmap("wellId", "11", 
              "depthLowerBound", 50, 
              "initialBitDepth", 1000, 
              "stepSize", 50))->result:seq at the end
=> @for => @yield => -{swab.maxPipeSpeed}# as {Max surge Speed}, depth# as depth
```

## **Maximum and Minimum trip - ECD**

### Surge

Computes surge equivalent circulating density in drill string trip

```javascript
og.model.surge.tripLimits(
         newmap("wellId", "{well_id}",  
                "pipeSpeed", value_m/s,
                "depthLowerBound", value_m,
                "initialBitDepth", value_m, 
                "computationUom", "kg/m3",
                "bitStepSize", value_m,
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

**Output: Max and Min Surge ECD (kg/m3) vs Depth**

### Swab

Computes swab equivalent circulating density in drill string trip

```javascript
og.model.swab.tripLimits(
         newmap("wellId", "{well_id}",  
                "pipeSpeed", value_m/s,
                "depthLowerBound", value_m,
                "initialBitDepth", value_m, 
                "computationUom", "kg/m3",
                "bitStepSize", value_m,
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

## **Maximum and Minimum trip - Pressure**

### Surge

Computes surge pressure in drill string trip

```javascript
og.model.surge.tripLimits(
         newmap("wellId", "{well_id}",  
                "pipeSpeed", value_m/s,
                "depthLowerBound", value_m,
                "initialBitDepth", value_m, 
                "computationUom", "Pa",
                "bitStepSize", value_m,
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

**Output: Max and Min Surge Pressure (Pa) vs Depth**

### **Swab**

**Computes swab pressure in drill string trip**

```javascript
og.model.swab.tripLimits(
         newmap("wellId", "{well_id}",  
                "pipeSpeed", value_m/s,
                "depthLowerBound", value_m,
                "initialBitDepth", value_m, 
                "computationUom", "Pa",
                "bitStepSize", value_m,
                "maxSectionLength", value_m, 
                "minSectionLength", value_m,
                "closedEnded", boolean)
)
```

**Output: Max and Min Swab Pressure (Pa) vs Depth**

## Input Parameters Description

| **Parameters**                             | **Description**                                                           | **unit**         |
| ------------------------------------------ | ------------------------------------------------------------------------- | ---------------- |
| **wellId**                                 | **Well Id**                                                               | **String**       |
| <p><strong>computationUom</strong><br></p> | **If ‘Pa’ output pressure or ‘kg/m3’ output is equivalent density**       | **string**       |
| **depthLowerBound**                        | **Bottom Depth (bit depth)**                                              | **m**            |
| **bitDepth**                               | **Casing Shoe depth**                                                     | **m**            |
| **atDepth**                                | **Choose specific depth**                                                 | **m**            |
| **bitStepSize**                            | **Step size length (discretization)**                                     | **m**            |
| **pipeSpeed**                              | **Drill string or casing speed**                                          | **m/s**          |
| **minSectionLength**                       | **Minimum section length for integration**                                | **m**            |
| **maxSectionLength**                       | **Maximum section length for integration**                                | **m**            |
| **closedEnded**                            | **Close or open ended geometry. Default is true (close ended)**           | **boolean**      |
| **sectionIndex**                           | **Set the index of the section. Default is empty, uses the last section** | **Number (int)** |


---

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